fixing import for tests

* chore: cleaning gitignore

* formating and env documentation

* feat: context switching of hotel/airline depndent on env var via middleware

* fixed alignment and building

* wrong file

* prods

* fixed applying style

* better session cookie management

* tentative session storage with maybe using airtable

* migrated api of ingestion

* events and products apge

* fixing build

* 13 create outline for research paper draft (#18)

* updated outline for paper from issue

* extra paper sections and some formalization of series data

* algorithms and acknowledgements

* updated outline for paper from issue

* upadted text formating

* event unification

* refactor tracking to ues callbacks instead of refs

* implement a pricing display api with session passing

* moved middleware to proxy according to new changes in Nextjs

* refactoed kafka ingestion to go via backend not web-db

* Refactor docker-compose services to use individual Dockerfiles (#20)

* Initial plan

* Refactor services into individual Dockerfiles

Co-authored-by: velocitatem <60182044+velocitatem@users.noreply.github.com>

* Add EXPOSE directives to all Dockerfiles with port documentation

Co-authored-by: velocitatem <60182044+velocitatem@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: velocitatem <60182044+velocitatem@users.noreply.github.com>

* fixing small bugs and adding exepriments to tracking

* added some doc

.env.example

@@ -1,5 +1,18 @@
-HOSTNAME=localhost
+# Network configuration
+HOSTNAME=localhost  # hostname for service discovery across docker network
 
-# PORTS
+# Application configuration
-KAFKA_PORT=9092
+STORE_MODE=hotel  # platform mode: 'hotel' or 'airline' - determines product catalog and UI theme
-REDIS_PORT=6377
+NEXT_PUBLIC_API_BASE=http://localhost:3000  # base URL for API endpoints, must be valid URL format
+NEXT_PUBLIC_APP_ENV=dev  # application environment: 'dev' or 'prod' - controls logging, error handling
+NEXT_PUBLIC_HOVER_THRESHOLD=1200  # hover threshold in milliseconds for UI interactions
+
+# Backend service
+BACKEND_URL=http://localhost:5000  # backend API URL for kafka ingestion (set to railway service URL in prod)
+
+# Service ports - used by docker-compose and service communication
+BACKEND_PORT=5000  # backend server port for kafka ingestion API
+KAFKA_HOST=localhost  # kafka broker hostname - set to remote host in prod (e.g., kafka.example.com)
+KAFKA_PORT=9092  # kafka broker port for event streaming
+REDIS_PORT=6377  # redis port for worker queue and caching
+REDPANDA_CONSOLE_PORT=8084  # redpanda console UI port for kafka monitoring

.github/workflows/pytest.yml

@@ -0,0 +1,30 @@
+name: Run Tests
+on:
+  push:
+    paths:
+      - 'experiments/**'
+      - 'backend/**'
+      - 'requirements.txt'
+      - '.github/workflows/pytest.yml'
+  pull_request:
+    paths:
+      - 'experiments/**'
+      - 'backend/**'
+      - 'requirements.txt'
+      - '.github/workflows/pytest.yml'
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: '3.13'
+          cache: 'pip'
+      - name: Install dependencies
+        run: |
+          python -m venv .venv
+          .venv/bin/pip install --upgrade pip
+          .venv/bin/pip install -r requirements.txt
+      - name: Run tests
+        run: .venv/bin/pytest -v

.gitignore

@@ -1,2 +1,8 @@
 **/.env
 **/.venv
+**/__pycache__
+**/.ipynb_checkpoints/
+**/.virtual_documents/
+**/session_*.svg
+**/*graph.svg
+paper/src/bib/auto

Makefile

@@ -4,6 +4,10 @@ BUILDDIR  := build
 TEX       := main.tex
 JOBNAME   := main
 PDF       := paper/$(BUILDDIR)/$(JOBNAME).pdf
+VENV      := .venv
+PYTHON    := $(VENV)/bin/python
+PIP       := $(VENV)/bin/pip
+PYTEST    := $(VENV)/bin/pytest
 
 .DEFAULT_GOAL := help
 
@@ -35,5 +39,14 @@ clean:
 	$(LATEXMK) -C -jobname=$(JOBNAME) -outdir=../$(BUILDDIR) || true
 	rm -rf paper/$(BUILDDIR)/*
 
+$(VENV):
+	python3 -m venv $(VENV)
+	$(PIP) install --upgrade pip
 
-.PHONY: all pdf clean watch run.webapp
+install: $(VENV)
+	$(PIP) install -r requirements.txt
+
+test: $(VENV)
+	$(PYTEST) -v
+
+.PHONY: all pdf clean watch run.webapp install test

README.md

@@ -1 +1,5 @@
 [![Build PDF](https://github.com/velocitatem/PHANTOM/actions/workflows/latex.yml/badge.svg)](https://github.com/velocitatem/PHANTOM/actions/workflows/latex.yml)
+
+- https://phantom-hotel.vercel.app/
+- https://phantom-airline.vercel.app/
+

backend/server/app.py

@@ -0,0 +1,189 @@
+# boilerplate code
+from fastapi import FastAPI, HTTPException
+from fastapi.middleware.cors import CORSMiddleware
+from pydantic import BaseModel
+from typing import Optional, Any
+import uvicorn
+import os
+import json
+from datetime import datetime
+from kafka import KafkaProducer, KafkaAdminClient, KafkaConsumer
+from kafka.admin import NewTopic
+from kafka.errors import TopicAlreadyExistsError
+from dotenv import load_dotenv
+load_dotenv()
+
+app = FastAPI()
+
+# kafka producer - lazy init
+_producer: Optional[KafkaProducer] = None
+
+def get_producer() -> KafkaProducer:
+    global _producer
+    if _producer is None:
+        host = os.getenv('KAFKA_HOST', 'localhost')
+        port = os.getenv('KAFKA_PORT', '9092')
+        broker = f'{host}:{port}' if port else host
+        print(f"[KAFKA_INIT] Connecting to broker: {broker}")
+        _producer = KafkaProducer(
+            bootstrap_servers=[broker],
+            value_serializer=lambda v: json.dumps(v).encode('utf-8'),
+            key_serializer=lambda k: k.encode('utf-8') if k else None,
+            acks=1,
+            retries=3,
+            max_in_flight_requests_per_connection=5,
+            request_timeout_ms=30000,
+            api_version_auto_timeout_ms=10000,
+            max_block_ms=5000,  # don't block send() for more than 5s
+        )
+        print(f"[KAFKA_INIT] Producer created successfully")
+    return _producer
+
+class EventPayload(BaseModel):
+    sessionId: str
+    eventName: str
+    page: str
+    productId: Optional[str] = None
+    metadata: Optional[dict[str, Any]] = None
+    storeMode: str
+    userAgent: Optional[str] = None
+    ts: Optional[str] = None
+
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],
+    allow_credentials=True,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+@app.on_event("startup")
+async def startup_event():
+    """create kafka topics on startup"""
+    host = os.getenv('KAFKA_HOST', 'localhost')
+    port = os.getenv('KAFKA_PORT', '9092')
+    broker = f'{host}:{port}'
+
+    try:
+        print(f"[STARTUP] Creating Kafka topics on {broker}")
+        admin = KafkaAdminClient(
+            bootstrap_servers=[broker],
+            request_timeout_ms=10000,
+        )
+
+        topics = [
+            NewTopic(name='user-interactions', num_partitions=3, replication_factor=1)
+        ]
+
+        admin.create_topics(new_topics=topics, validate_only=False)
+        print(f"[STARTUP] Topics created successfully")
+        admin.close()
+    except TopicAlreadyExistsError:
+        print(f"[STARTUP] Topics already exist, skipping creation")
+    except Exception as e:
+        print(f"[STARTUP] Failed to create topics: {e}")
+        print(f"[STARTUP] Will rely on auto-creation on first message")
+
+@app.get("/health")
+async def health():
+    kafka_status = "unknown"
+    try:
+        producer = get_producer()
+        # attempt to get cluster metadata to verify connection
+        producer.bootstrap_connected()
+        kafka_status = "connected"
+    except Exception as e:
+        kafka_status = f"error: {str(e)}"
+
+    return {
+        "status": "healthy",
+        "kafka": kafka_status,
+        "kafka_broker": f"{os.getenv('KAFKA_HOST', 'localhost')}:{os.getenv('KAFKA_PORT', '9092')}"
+    }
+
+
+@app.post("/api/kafka/ingest")
+async def ingest_logs(event: EventPayload):
+    try:
+        if not event.ts:
+            event.ts = datetime.utcnow().isoformat() + 'Z'
+
+        producer = get_producer()
+        future = producer.send(
+            'user-interactions',
+            key=event.sessionId,
+            value=event.model_dump()
+        )
+        # add callback for error logging but don't block
+        future.add_errback(lambda e: print(f"[KAFKA_SEND_ERROR] {e}"))
+
+        return {"success": True}
+    except Exception as e:
+        import traceback
+        print(f"[ERROR] {e}")
+        print(traceback.format_exc())
+        raise HTTPException(status_code=500, detail=str(e))
+
+@app.get("/api/kafka/dump")
+def dump_logs(
+    last_n: Optional[int] = None,
+    t_start: Optional[str] = None,
+    t_end: Optional[str] = None
+):
+    """dump all messages from user-interactions topic
+
+    params:
+        last_n: return only last n messages (default: all)
+        t_start: filter by start timestamp iso format (future use)
+        t_end: filter by end timestamp iso format (future use)
+    """
+    host = os.getenv('KAFKA_HOST', 'localhost')
+    port = os.getenv('KAFKA_PORT', '9092')
+    broker = f'{host}:{port}'
+
+    try:
+        consumer = KafkaConsumer(
+            'user-interactions',
+            bootstrap_servers=[broker],
+            auto_offset_reset='earliest',
+            enable_auto_commit=False,
+            value_deserializer=lambda x: json.loads(x.decode('utf-8')),
+            consumer_timeout_ms=5000
+        )
+
+        events = []
+        for msg in consumer:
+            events.append(msg.value)
+
+        consumer.close()
+
+        # apply filters
+        if t_start or t_end:
+            # filter by timestamp range if provided
+            filtered = []
+            for e in events:
+                ts = e.get('ts')
+                if ts:
+                    if t_start and ts < t_start:
+                        continue
+                    if t_end and ts > t_end:
+                        continue
+                filtered.append(e)
+            events = filtered
+
+        if last_n and last_n > 0:
+            events = events[-last_n:]
+
+        return {"success": True, "count": len(events), "data": events}
+
+    except Exception as e:
+        import traceback
+        print(f"[DUMP_ERROR] {e}")
+        print(traceback.format_exc())
+        raise HTTPException(status_code=500, detail=str(e))
+
+
+
+if __name__ == "__main__":
+    PORT=int(os.getenv("BACKEND_PORT", 5000))
+    uvicorn.run("server:app", host="0.0.0.0", port=PORT, reload=True)

backend/server/requirements.txt

@@ -0,0 +1,5 @@
+fastapi==0.104.1
+uvicorn[standard]==0.24.0
+kafka-python==2.0.2
+pydantic==2.5.0
+python-dotenv==1.0.0

docker-compose.yml

@@ -1,15 +1,34 @@
 services:
+  backend:
+    container_name: "PHANTOM-backend"
+    build:
+      context: .
+      dockerfile: docker/backend.Dockerfile
+    ports:
+      - "${BACKEND_PORT:-5000}:5000"
+    environment:
+      - KAFKA_HOST=kafka
+      - KAFKA_PORT=29092
+    depends_on:
+      - kafka
+    restart: unless-stopped
+
   redis:
     container_name: "PHANTOM-redis"
-    image: redis:7-alpine
+    build:
+      context: ./docker
+      dockerfile: Redis.dockerfile
     ports:
       - "${REDIS_PORT:-6378}:6379"
     volumes:
       - phantom_redis_data:/data
     restart: unless-stopped
+
   zookeeper:
     container_name: "PHANTOM-zookeeper"
-    image: confluentinc/cp-zookeeper:latest
+    build:
+      context: ./docker
+      dockerfile: Zookeeper.dockerfile
     environment:
       ZOOKEEPER_CLIENT_PORT: 2181
     ports:
@@ -17,7 +36,9 @@ services:
 
   kafka:
     container_name: "PHANTOM-kafka"
-    image: confluentinc/cp-kafka:7.5.0
+    build:
+      context: ./docker
+      dockerfile: Kafka.dockerfile
     depends_on:
       - zookeeper
     environment:
@@ -36,7 +57,9 @@ services:
 
   redpanda-console:
     container_name: "PHANTOM-redpanda-console"
-    image: docker.redpanda.com/redpandadata/console:latest
+    build:
+      context: ./docker
+      dockerfile: RedpandaConsole.dockerfile
     depends_on:
       - kafka
     environment:

docker/Kafka.dockerfile

@@ -0,0 +1,7 @@
+FROM confluentinc/cp-kafka:7.5.0
+
+# Expose Kafka ports
+# 9092: External client connections
+# 29092: Internal broker communication
+# 9999: JMX monitoring port
+EXPOSE 9092 29092 9999

docker/Redis.dockerfile

@@ -0,0 +1,4 @@
+FROM redis:7-alpine
+
+# Expose Redis port
+EXPOSE 6379

docker/RedpandaConsole.dockerfile

@@ -0,0 +1,4 @@
+FROM docker.redpanda.com/redpandadata/console:latest
+
+# Expose Redpanda Console web UI port
+EXPOSE 8080

docker/Zookeeper.dockerfile

@@ -0,0 +1,4 @@
+FROM confluentinc/cp-zookeeper:latest
+
+# Expose Zookeeper client port
+EXPOSE 2181

docker/backend.Dockerfile

@@ -0,0 +1,12 @@
+FROM python:3.11-slim
+
+WORKDIR /app
+
+COPY backend/server/requirements.txt .
+RUN pip install --no-cache-dir -r requirements.txt
+
+COPY backend/server/app.py .
+
+EXPOSE 5000
+
+CMD ["uvicorn", "app:app", "--host", "0.0.0.0", "--port", "5000"]

experiments/agents/__init__.py

@@ -0,0 +1 @@
+"""Agentic behavior runner for PHANTOM research platform."""

experiments/agents/agent.py

@@ -0,0 +1,44 @@
+from .base import Agent as BaseAgent
+from browser_use import Browser, Agent, ChatOpenAI
+from enum import Enum
+
+class AgentTypes(str, Enum):
+    GENERIC_BROWSER_USE_AGENT = "generic_browser_use_agent"
+
+def _build_prompt(goal : str, environment_url : str) -> str:
+    #TODO: Improve prompt engineering here and experiment with
+    return f"""You are an autonomous agent tasked with achieving the following goal: {goal}
+You have access to a web browser to interact with the environment at {environment_url}.
+Use the browser to navigate, gather information, and perform actions necessary to accomplish your goal.
+Be thorough and ensure you complete the task fully."""
+
+class GenericBrowserUseAgent(BaseAgent):
+    def __init__(self,
+                 goal: str,
+                 url: str = "http://localhost:3000",
+                 timeout: int = 300,
+                 llm_model: str = "gpt-5-mini",
+                 headless: bool = True):
+        super().__init__(goal, url, timeout)
+        self.llm_model = ChatOpenAI(model=llm_model)
+        self.browser = Browser(headless=headless)
+        self.agent = Agent(task=_build_prompt(goal, url),
+                           llm=self.llm_model,
+                           browser=self.browser)
+    async def act(self) -> str:
+        self.result = await self.agent.run()
+        # https://github.com/browser-use/browser-use/blob/main/browser_use/agent/views.py#L301
+        return self.result.final_result()
+
+def get_agent(agent_type: AgentTypes,  **kwargs) -> Agent:
+    if agent_type == AgentTypes.GENERIC_BROWSER_USE_AGENT:
+        return GenericBrowserUseAgent(**kwargs)
+    else:
+        raise ValueError(f"Unknown agent type: {agent_type}")
+
+if __name__ == "__main__":
+    import asyncio
+    JTBD= "Name all the products on this site and try to find out more about each product by clicking into them (they might not open)"
+    agent = get_agent(AgentTypes.GENERIC_BROWSER_USE_AGENT, goal=JTBD, url="http://localhost:3000/products", timeout=300)
+    R=asyncio.run(agent.act())
+    print(R)

experiments/agents/base.py

@@ -0,0 +1,19 @@
+from abc import ABC, abstractmethod
+from typing import Optional
+
+class Agent(ABC):
+    """Base interface for browser automation agents"""
+
+    def __init__(self, goal: str, url: str = "http://localhost:3000", timeout: int = 300):
+        self.goal = goal
+        self.url = url
+        self.timeout = timeout
+        self.result: Optional[str] = None
+
+    @abstractmethod
+    async def act(self) -> str:
+        """Execute goal and return result text"""
+        pass
+
+    def final_result(self) -> Optional[str]:
+        return self.result

experiments/agents/test.py

@@ -0,0 +1,30 @@
+import pytest
+import asyncio
+from experiments.agents.agent import get_agent, AgentTypes
+import os
+
+
+def test_agent_init():
+    agent = get_agent(AgentTypes.GENERIC_BROWSER_USE_AGENT, goal="test", url="http://example.com", timeout=100)
+    assert agent.goal == "test"
+    assert agent.url == "http://example.com"
+    assert agent.timeout == 100
+
+
+def test_invalid_agent():
+    with pytest.raises(ValueError):
+        get_agent("invalid", goal="test")
+
+
+@pytest.mark.asyncio
+@pytest.mark.skipif("OPENAI_API_KEY" not in os.environ, reason="OPENAI_API_KEY not set")
+async def test_agent_execution():
+    agent = get_agent(AgentTypes.GENERIC_BROWSER_USE_AGENT, goal="get page title", url="https://example.com", timeout=60)
+
+    result = await agent.act()
+    assert result
+    assert agent.final_result()
+    assert agent.final_result().history[-1].result[-1].is_done == True
+    assert isinstance(result, str)
+    assert "example" in result.lower()
+    assert len(result) > 0

experiments/procesing/extract.py

@@ -0,0 +1,84 @@
+import pandas as pd
+import json
+import numpy as np
+import os
+import requests
+from dotenv import load_dotenv
+from sklearn.base import BaseEstimator, TransformerMixin
+load_dotenv()
+
+BACKEND_URL = os.getenv("BACKEND_URL", "http://localhost:5000")
+N_PRICE_BUCKETS = 5
+
+def get_data_from_kafka() -> pd.DataFrame:
+    """fetch all events from backend dump endpoint"""
+    resp = requests.get(f"{BACKEND_URL}/api/kafka/dump")
+    resp.raise_for_status()
+    data = resp.json()
+
+    if not data.get('success') or not data.get('data'):
+        return pd.DataFrame()
+
+    df = pd.DataFrame(data['data'])
+    # explode metadata col json
+    if 'metadata' in df.columns:
+        df = df.join(pd.json_normalize(df.pop("metadata"), sep=".").add_prefix("metadata_"))
+    df = df.dropna(subset=['eventName'])
+    return df
+
+
+def join_with_experiments(df: pd.DataFrame) -> pd.DataFrame:
+    # TODO: Get experiments db from supabase and join on session_id
+    return df
+
+
+def augment_event_titles(df: pd.DataFrame) -> pd.DataFrame:
+    # from taking standard view_item_page in eventName to view_item_page_{metadata_schema}
+    # we want metadata schema to create product specific event names
+
+    # only create price buckets if we have enough unique prices
+    if df["metadata_price"].notnull().sum() > 0:
+        try:
+            price_buckets = pd.qcut(
+                df["metadata_price"],
+                q=N_PRICE_BUCKETS,
+                labels=[f"PB_{i+1}" for i in range(N_PRICE_BUCKETS)],
+                duplicates='drop'  # handle duplicate bin edges
+            )
+        except ValueError:
+            # fallback: if still not enough unique values, use cut with fixed ranges or just use raw price
+            price_buckets = df["metadata_price"].apply(lambda x: f"P_{int(x)}" if pd.notnull(x) else "")
+    else:
+        price_buckets = pd.Series([""] * len(df), index=df.index)
+
+    # metadata_schema: _product_id@price_bucket_{i} only if we have product metadata otherswise keep original event name
+    # TODO: make this adaptive, if we have hover_over_title we append the title, if its view_page we say which page
+    df["metadata_schema"] = np.where(
+        df["productId"].notnull() & df["metadata_price"].notnull(),
+        "_" + df["productId"].astype(str) + "@" + price_buckets.astype(str),
+        ""
+    )
+    df["eventName"] = df["eventName"] + df["metadata_schema"].astype(str)
+    return df
+
+
+def extract() -> pd.DataFrame:
+    df = get_data_from_kafka()
+    df = join_with_experiments(df)
+    df = augment_event_titles(df)
+    return df
+
+
+class DataExtractor(BaseEstimator, TransformerMixin):
+    def fit(self, X=None, y=None):
+        return self
+
+    def transform(self, X=None):
+        return extract()
+
+
+if __name__ == "__main__":
+    df = extract()
+    print(df.head())
+    print(df.tail())
+    print(df.info())

experiments/procesing/mapping.py

@@ -0,0 +1,158 @@
+import numpy as np
+import pandas as pd
+from sklearn.base import BaseEstimator, TransformerMixin
+
+def build_transition_prob_matrix(df: pd.DataFrame):
+    df = df.dropna(subset=['eventName'])
+    events = df['eventName'].tolist()
+    labels = pd.Index(events).unique().tolist()
+    idx = {e:i for i,e in enumerate(labels)}
+    M = np.zeros((len(labels), len(labels)), dtype=float)
+    for a, b in zip(events, events[1:]):
+        M[idx[a], idx[b]] += 1
+    row_sums = M.sum(axis=1, keepdims=True)
+    with np.errstate(divide='ignore', invalid='ignore'):
+        P = np.divide(M, row_sums, where=row_sums>0)  # row-normalized
+    return P, labels
+
+# https://medium.com/data-science/time-series-data-markov-transition-matrices-7060771e362b
+from graphviz import Digraph
+import numpy as np
+import pandas as pd
+
+def _as_prob_df(matrix, labels=None):
+    """Return a square DataFrame with index=columns=labels."""
+    if isinstance(matrix, pd.DataFrame):
+        # Ensure square and aligned
+        assert (matrix.index == matrix.columns).all(), "Index/columns must match."
+        return matrix
+    matrix = np.asarray(matrix, dtype=float)
+    assert matrix.shape[0] == matrix.shape[1], "Matrix must be square."
+    if labels is None:
+        raise ValueError("labels are required when matrix is not a DataFrame")
+    assert len(labels) == matrix.shape[0], "labels length must match matrix size."
+    return pd.DataFrame(matrix, index=list(labels), columns=list(labels))
+
+def _df_to_edgelist(P: pd.DataFrame, threshold=0.0, round_digits=2):
+    """Build weighted edges > threshold."""
+    edges = []
+    for src in P.index:
+        for dst in P.columns:
+            w = float(P.loc[src, dst])
+            if w > threshold:
+                edges.append((str(src), str(dst), f"{w:.{round_digits}f}"))
+    return edges
+
+def render_graph(fname, matrix, ls_index=None, threshold=0.0, fmt="svg", view=False):
+    """
+    fname: output file stem (no extension)
+    matrix: NumPy array or pandas DataFrame of transition PROBABILITIES
+    ls_index: ordered labels (required if matrix is not a DataFrame)
+    threshold: hide edges with weight <= threshold
+    fmt: 'svg'|'png'|'pdf' etc.
+    view: open after rendering
+    """
+    P = _as_prob_df(matrix, labels=ls_index)
+    edges = _df_to_edgelist(P, threshold=threshold)
+
+    g = Digraph(format=fmt)
+    g.attr(rankdir="LR", size="30")
+    g.attr("node", shape="circle")
+
+    # ensure isolated nodes appear
+    for node in P.index:
+        g.node(str(node), width="1", height="1")
+
+    for src, dst, label in edges:
+        g.edge(src, dst, label=label)
+
+    g.render(fname, view=view, cleanup=True)
+    return g
+
+
+class TransitionProbMatrixTransformer(BaseEstimator, TransformerMixin):
+    def __init__(self, threshold=0.0):
+        self.threshold = threshold
+        self.P_ = None
+        self.labels_ = None
+
+    def fit(self, X: pd.DataFrame, y=None):
+        P, labels = build_transition_prob_matrix(X)
+        self.P_ = P
+        self.labels_ = labels
+        return self
+
+    def transform(self, X: pd.DataFrame = None):
+        return self.P_, self.labels_
+
+    def render(self, fname: str, fmt="svg", view=False):
+        if self.P_ is None or self.labels_ is None:
+            raise ValueError("Transformer has not been fitted yet.")
+        return render_graph(
+            fname,
+            self.P_,
+            ls_index=self.labels_,
+            threshold=self.threshold,
+            fmt=fmt,
+            view=view
+        )
+
+
+class SessionTransitionProbMatrixTransformer(BaseEstimator, TransformerMixin):
+    def __init__(self, threshold=0.0, session_col='sessionId'):
+        self.threshold = threshold
+        self.session_col = session_col
+        self.session_matrices_ = None
+
+    def fit(self, X: pd.DataFrame, y=None):
+        if self.session_col not in X.columns:
+            raise ValueError(f"Column '{self.session_col}' not found in DataFrame")
+
+        session_matrices = {}
+        for session_id, grp in X.groupby(self.session_col):
+            if len(grp) > 1:  # need at least 2 events for transitions
+                P, labels = build_transition_prob_matrix(grp)
+                session_matrices[session_id] = {'matrix': P, 'labels': labels}
+
+        self.session_matrices_ = session_matrices
+        return self
+
+    def transform(self, X: pd.DataFrame = None):
+        if self.session_matrices_ is None:
+            raise ValueError("Transformer has not been fitted yet.")
+        return pd.Series(self.session_matrices_)
+
+    def render_session(self, session_id: str, fname: str, fmt="svg", view=False):
+        if self.session_matrices_ is None:
+            raise ValueError("Transformer has not been fitted yet.")
+        if session_id not in self.session_matrices_:
+            raise ValueError(f"Session '{session_id}' not found in fitted data.")
+
+        sess_data = self.session_matrices_[session_id]
+        return render_graph(
+            fname,
+            sess_data['matrix'],
+            ls_index=sess_data['labels'],
+            threshold=self.threshold,
+            fmt=fmt,
+            view=view
+        )
+if __name__ == "__main__":
+    # Example usage
+    data = {
+        'eventName': [
+            'A', 'B', 'A', 'C', 'B', 'A', 'A', 'C', 'B', 'C',
+            'A', 'B', 'C', 'A', 'B', 'C', 'A', 'B', 'C', 'A'
+        ]
+    }
+    df = pd.DataFrame(data)
+
+    transformer = TransitionProbMatrixTransformer(threshold=0.1)
+    transformer.fit(df)
+    P, labels = transformer.transform(None)
+
+    print("Transition Probability Matrix:")
+    print(pd.DataFrame(P, index=labels, columns=labels))
+
+    # Render the graph
+    transformer.render("transition_graph", fmt="svg", view=False)

experiments/procesing/pipeline.py

@@ -0,0 +1,19 @@
+from sklearn.pipeline import Pipeline
+from sklearn.preprocessing import StandardScaler
+from extract import DataExtractor
+from mapping import SessionTransitionProbMatrixTransformer, render_graph
+
+
+if __name__ == "__main__":
+    steps = [
+        ('data_extraction', DataExtractor()),
+        ('transition_matrix', SessionTransitionProbMatrixTransformer(threshold=0.05)),
+    ]
+    pipeline = Pipeline(steps)
+    result = pipeline.fit_transform(None)
+    print(f"Number of sessions: {len(result)}\n")
+
+    for session_id, sess_data in result.items():
+        fname = f"session_{session_id}"
+        render_graph(fname, sess_data['matrix'], ls_index=sess_data['labels'], threshold=0.05, fmt="svg", view=False)
+        print(f"Rendered {fname}.svg")

paper/concat_code.sh

@@ -16,10 +16,11 @@ mkdir -p "$(dirname "$OUTPUT_FILE")"
 add_file() {
     local filepath="$1"
     local relpath="${filepath#$PROJECT_ROOT/}"
+    local escaped_path="${relpath//_/\\_}"
 
     # Add section header and code listing (no language-specific highlighting)
-    echo "\\subsection{${relpath}}" >> "$OUTPUT_FILE"
+    echo "\\subsection{${escaped_path}}" >> "$OUTPUT_FILE"
-    echo "\\begin{lstlisting}[caption={${relpath}}]" >> "$OUTPUT_FILE"
+    echo "\\begin{lstlisting}[caption={${escaped_path}}]" >> "$OUTPUT_FILE"
     cat "$filepath" >> "$OUTPUT_FILE"
     echo "" >> "$OUTPUT_FILE"
     echo "\\end{lstlisting}" >> "$OUTPUT_FILE"

paper/src/auto/main.el

@@ -22,4 +22,3 @@
    (TeX-add-symbols
     '("footnotetextcopyrightpermission" 1)))
  :latex)
-

paper/src/bib/references.bib

@@ -1,98 +0,0 @@
-@phdthesis{,
-   abstract = {Algorithmic pricing is an emerging business practice that uses computational algorithms to determine
-the prices of products and services based on a number of dynamic factors. The aim of this thesis is to
-draw attention to the existence of these business practices, and the ethical and social implications that
-derive from them, and then focus on what could be effective solutions to increase the well-being of
-the community.
-In Chapter 2 of the thesis, a general introduction to the topic will be made, starting from its history
-and its evolution over the years; Chapter 3 will examine the different types of pricing algorithms.
-Subsequently, in Chapter 4 we will analyze the sectors in which they are most applicable, and the
-relative advantages and disadvantages they bring with them, with a critical analysis of the trade-offs
-generated. The effect of algorithmic pricing on competition will be studied, considering how the
-ability of algorithms to adapt quickly to market conditions can foster anti-competitive practices, such
-as price discrimination. Later, in Chapter 5, we will look at the issue of price transparency and how
-the opacity of algorithms can make it difficult for consumers to understand the pricing process and
-assess whether they are receiving fair treatment.
-To address these ethical issues, several possible solutions will be brought to light, described in
-Chapter 6, which will focus on the role of the government, as a regulatory, of the end consumer, who
-must be encouraged to educate and inform himself about the use of these practices, and of the
-company, as responsible for making its customers aware and acting in compliance with government
-laws, for fair and non-discriminatory use.},
-   author = {Fabio Salassa and Paolo Pautassi},
-   school = {Politecnico di Torino},
-   title = {Politecnico di Torino Algorithmic Pricing in the digital age "Ethical considerations on its economic and social implications, and an analysis of possible solutions to overcome its critical issues" Tutor: Candidate},
-   url = {https://webthesis.biblio.polito.it/secure/31375/1/tesi.pdf}
-}
-@inproceedings{Mueller2019,
-   author = {Jonas W Mueller and Vasilis Syrgkanis and Matt Taddy},
-   booktitle = {Advances in Neural Information Processing Systems 32 (NeurIPS 2019)},
-   pages = {15442-15452},
-   title = {Low-Rank Bandit Methods for High-Dimensional Dynamic Pricing},
-   url = {https://proceedings.neurips.cc/paper/2019/file/0a3df70393993583a13c0dd6686f3f32-Paper.pdf},
-   year = {2019}
-}
-@article{Prez-Ricardo2025,
-   abstract = {The study aims to explore tourists' booking intentions by analyzing the price elasticity of demand in tourist accommodations. This analysis should reveal how changes in price affect booking behavior across different customer segments, using online booking records. A dataset was compiled from 106 hotels in Malaga, Spain, comprising 27,910 online bookings sourced exclusively from hotel websites. To understand the price elasticity of demand, a simple log-log regression was applied, segmenting the data based on key revenue-related variables. Subsequently, a cluster segmentation was performed using the Elbow method and K-means algorithm to identify distinct market segments. The findings highlighted that Family Travelers and Short Stay Travelers segments exhibited elastic demand, indicating higher sensitivity to price fluctuations. In contrast, Early Bookers and Mid-Season Long Stayers demonstrated inelastic demand, with lower responsiveness to changes in tourist accommodation prices. The number of variables analyzed in this study, along with the cluster analysis, represent a novelty and contribute to the existing literature on market segmentation and price elasticity of demand. This integration enriches both fields of research, offering mutual benefits and deeper insights that enhance the understanding of booking intention and pricing strategies.},
-   author = {Elizabeth del Carmen Pérez-Ricardo and Josefa García-Mestanza},
-   doi = {10.1016/j.iedeen.2025.100271},
-   issn = {24448834},
-   issue = {1},
-   journal = {European Research on Management and Business Economics},
-   keywords = {Booking intention,Price elasticity,Tourist segmentation},
-   month = {1},
-   publisher = {European Academy of Management and Business Economics},
-   title = {Exploring booking intentions through price elasticity of demand in tourism accommodations using large-scale data analytics},
-   volume = {31},
-   year = {2025}
-}
-@article{ArnoudVdenBoer2015,
-   author = {Arnoud V. den Boer},
-   doi = {10.1016/j.sorms.2015.03.001},
-   issue = {1},
-   journal = {Surveys in Operations Research and Management Science},
-   month = {6},
-   pages = {1-18},
-   title = {Dynamic pricing and learning: Historical origins, current research, and new directions},
-   volume = {20},
-   url = {https://www.sciencedirect.com/science/article/pii/S1876735415000021},
-   year = {2015}
-}
-@article{Iliou2021,
-   author = {Christos Iliou and Theodoros Kostoulas and Theodora Tsikrika and Vasilis Katos and Stefanos Vrochidis and Ioannis Kompatsiaris},
-   doi = {10.1145/3447815},
-   issue = {3},
-   journal = {Digital Threats: Research and Practice},
-   pages = {1-26},
-   title = {Detection of Advanced Web Bots by Combining Web Logs with Mouse Behavioural Biometrics},
-   volume = {2},
-   url = {https://dl.acm.org/doi/10.1145/3447815},
-   year = {2021}
-}
-@article{Amjad2017,
-   abstract = { In this paper, the question of interest is estimating true demand of a product at a given store location and time period in the retail environment based on a single noisy and potentially censored observation. To address this question, we introduce a %non-parametric framework to make inference from multiple time series. Somewhat surprisingly, we establish that the algorithm introduced for the purpose of "matrix completion" can be used to solve the relevant inference problem. Specifically, using the Universal Singular Value Thresholding (USVT) algorithm [7], we show that our estimator is consistent: the average mean squared error of the estimated average demand with respect to the true average demand goes to 0 as the number of store locations and time intervals increase to $\infty$. We establish naturally appealing properties of the resulting estimator both analytically as well as through a sequence of instructive simulations. Using a real dataset in retail (Walmart), we argue for the practical relevance of our approach. },
-   author = {Muhammad J. Amjad and Devavrat Shah},
-   doi = {10.1145/3154489},
-   issue = {2},
-   journal = {Proceedings of the ACM on Measurement and Analysis of Computing Systems},
-   month = {12},
-   pages = {1-28},
-   publisher = {Association for Computing Machinery (ACM)},
-   title = {Censored Demand Estimation in Retail},
-   volume = {1},
-   url = {https://par.nsf.gov/servlets/purl/10066022},
-   year = {2017}
-}
-@article{Calvano2018,
-   author = {Emilio Calvano and Giacomo Calzolari and Vincenzo Denicolo and Sergio Pastorello},
-   doi = {10.2139/ssrn.3304991},
-   journal = {SSRN Electronic Journal},
-   title = {Artificial Intelligence, Algorithmic Pricing and Collusion},
-   url = {https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3304991},
-   year = {2018}
-}
-@misc{gha_ffary_day_2025_amazon_perplexit,
-   author = {Shirin Ghaffary and Matt Day},
-   note = {Updated 2025-11-05},
-   title = {Amazon Sues to Stop Perplexity From Using AI Tool to Buy Stuff},
-   url = {https://www.bloomberg.com/news/articles/2025-11-04/amazon-demands-perplexity-stop-ai-agent-from-making-purchases}
-}

paper/src/chapters/03-methodology.tex

@@ -5,7 +5,7 @@
 
 Mathematical formalization of agent-induced pricing distortions. Formal definition of potential loss mechanisms $\alpha D$
 
-We consider a business across time during which we have an evolving vector $p_t \in \Re^N$ where $N$ is the number of products in our catalogue. our price vector is directly dependent on a demand function $q_t$ which we define as a linear method of a price elasticity matrix $B_t$. This is the same setup that Microsoft created in their research. \autocite{Mueller2019}
+We consider a business across time during which we have an evolving vector $p_t \in \Re^N$ where $N$ is the number of products in our catalogue. our price vector is directly dependent on a demand function $q_t$ which we define as a linear method of a price elasticity matrix $B_t$. This is the same setup that Microsoft created in their research.
 
 We gether interaction data from users interacting with a sample platform simulating a hotel/airline which generates interaction distributions $I_t = \{(p_t, q_t^\text{obs}, \pi_t)\}_{t=1}^T$
 

paper/src/main.tex

@@ -29,7 +29,7 @@
 }
 
 \begin{abstract}
-  The primary objective of this thesis is to develop and validate pricing heuristics that protect e-commerce platforms from systematic exploitation by Large Language Model (LLM) agents within dynamic pricing environments. As AI agents increasingly mediate consumer transactions, they enable users to circumvent the Cost of Information (the price premium accumulated through demand signal expression) by conducting reconnaissance in isolated sessions before executing purchases through clean sessions at base prices. This research will make an anticipatory contribution by adapting recommendation system methodologies to distinguish between genuine human browsing behaviour and agent-orchestrated information gathering, thereby enabling pricing systems to maintain margin integrity without degrading the user experience for legitimate customers or getting rid of leads generated by LLMs.
+The primary objective of this thesis is to develop and validate pricing heuristics that protect e-commerce platforms from systematic exploitation by Large Language Model (LLM) agents within dynamic pricing environments. As AI agents increasingly mediate consumer transactions, they enable users to circumvent the Cost of Information (the price premium accumulated through demand signal expression) by conducting reconnaissance in isolated sessions before executing purchases through clean sessions at base prices. This research will make an anticipatory contribution by adapting recommendation system methodologies to distinguish between genuine human browsing behaviour and agent-orchestrated information gathering, thereby enabling pricing systems to maintain margin integrity without degrading the user experience for legitimate customers or getting rid of leads generated by LLMs.
 \end{abstract}
 
 \maketitle
@@ -42,10 +42,10 @@
 \input{chapters/06-conclusion}
 
 
-
-\onecolumn
 \printbibliography
+
 \clearpage
+\onecolumn
 \appendix
 \input{../build/concatenated_code}
 

paper/src/preamble.tex

@@ -20,7 +20,10 @@
     commentstyle=\color{green!60!black},
     stringstyle=\color{red},
     showstringspaces=false,
-    captionpos=b
+    captionpos=b,
+    inputencoding=utf8,
+    extendedchars=true,
+    literate={·}{{\textperiodcentered}}1 {−}{{\textminus}}1 {—}{{---}}1 {–}{{--}}1
 }
 
 % Use biblatex instead of natbib (acmart default)

pytest.ini

@@ -0,0 +1,7 @@
+[pytest]
+testpaths = experiments
+python_files = test*.py
+python_classes = Test*
+python_functions = test_*
+asyncio_mode = auto
+asyncio_default_fixture_loop_scope = function

requirements.txt

@@ -5,3 +5,8 @@ jupyter
 ipykernel
 matplotlib
 graphviz
+browser-use
+pytest
+pytest-asyncio
+uv
+scikit-learn

web/README.md

@@ -1,36 +1,97 @@
 This is a [Next.js](https://nextjs.org) project bootstrapped with [`create-next-app`](https://nextjs.org/docs/app/api-reference/cli/create-next-app).
 
-## Getting Started
+# Phantom Air/Hotels
 
-First, run the development server:
+Design Discovery Documentation: https://github.com/velocitatem/PHANTOM/wiki/Design-Discovery
 
-```bash
+> This webapp serves two modes `{HOTEL,AIRLINE}` which are given by an env variable
+
+The webapp should serve under the / route the landing page which for both platforms is very similar. We define a set of components like Hero, Card, Button, Link ... This we can then pass to specific components each mode might demand that makes it behave differently, hotel cards showing hotel rooms from database and airline cards showing flights from database and each fetching prices from the pricing provider with a different HTTP parameter.
+
+- globally we define a middleware.ts which is our switcher for modes.
+- /app will have (airline) and (hotel) children which each have a layout.tsx and page.tsx where /app also has a parent layout defining layout.tsx and globals.css for any shared styling to avoid repretition.
+- /components/ is gonna have ui/ which defines things like Button, Card, DatePicker with generic definitions and any tracking or observation code. We then define feats/airline/ and feats/hotel/ as children of components with specific components like AirlineHero and HotelCard.
+- in /styles/ we define airline.css and hotel.css to tailor accents and styling for each.
+
+## How to Run
+
+```sh
+# install deps
+npm install
+
+# set store mode (hotel or airline)
+export STORE_MODE=hotel
+
+# run dev server
 npm run dev
-# or
-yarn dev
-# or
-pnpm dev
-# or
-bun dev
 ```
 
-Open [http://localhost:3000](http://localhost:3000) with your browser to see the result.
+Server runs on `http://localhost:3000`
 
-You can start editing the page by modifying `app/page.tsx`. The page auto-updates as you edit the file.
+## Environment Variables
 
-This project uses [`next/font`](https://nextjs.org/docs/app/building-your-application/optimizing/fonts) to automatically optimize and load [Geist](https://vercel.com/font), a new font family for Vercel.
+| Variable | Description | Default | Example |
+|----------|-------------|---------|---------|
+| `HOSTNAME` | Server hostname | `localhost` | `localhost` |
+| `STORE_MODE` | Mode switch for platform | `hotel` | `hotel` or `airline` |
+| `NEXT_PUBLIC_API_BASE` | Public API base URL | `http://localhost:3000` | `http://localhost:3000` |
+| `NEXT_PUBLIC_APP_ENV` | Application environment | `dev` | `dev`, `prod` |
+| `NEXT_PUBLIC_HOVER_THRESHOLD` | Hover dwell threshold (ms) | `1200` | `1200` |
+| `BACKEND_URL` | Backend service URL | `http://localhost:5000` | `http://localhost:5000` |
 
-## Learn More
+## Routes
 
-To learn more about Next.js, take a look at the following resources:
+### Public Pages
+- `/` — Landing page (mode-aware root)
+- `/hotel` — Hotel mode landing
+- `/hotel/products` — Hotel catalog
+- `/airline` — Airline mode landing
+- `/airline/products` — Flight catalog
+- `/admin/experiments` — Experiment management UI
 
-- [Next.js Documentation](https://nextjs.org/docs) - learn about Next.js features and API.
+### API Routes
-- [Learn Next.js](https://nextjs.org/learn) - an interactive Next.js tutorial.
+- `GET /api/session` — Fetch or create session, sets httpOnly cookie
+- `GET /api/pricing?productId=X&sessionId=Y&experimentId=Z` — Get product price from provider
+- `POST /api/ingest` — Ingest event to Kafka via backend
+- `GET /api/admin/experiments` — List all experiments
+- `POST /api/admin/experiments/start` — Start new experiment for session
+- `POST /api/admin/experiments/stop` — Stop experiment by ID
 
-You can check out [the Next.js GitHub repository](https://github.com/vercel/next.js) - your feedback and contributions are welcome!
+## Event Catalog
 
-## Deploy on Vercel
+All events are ingested via `POST /api/ingest` and follow the `EventBase` schema. Below are the 17 canonical events:
 
-The easiest way to deploy your Next.js app is to use the [Vercel Platform](https://vercel.com/new?utm_medium=default-template&filter=next.js&utm_source=create-next-app&utm_campaign=create-next-app-readme) from the creators of Next.js.
+| Event Name | Category | Payload Example |
+|------------|----------|-----------------|
+| `session_start` | Session | `{ sessionId, experimentId?, storeMode, ts, page, eventName, userAgent? }` |
+| `page_view` | Navigation | `{ sessionId, experimentId?, storeMode, ts, page: "/hotel", eventName: "page_view" }` |
+| `view_item_page` | Discovery | `{ sessionId, storeMode, ts, page: "/hotel/products", productId: "H001", eventName: "view_item_page" }` |
+| `learn_more_about_item` | Discovery | `{ sessionId, storeMode, ts, page, productId, eventName: "learn_more_about_item" }` |
+| `add_item_to_cart` | Cart | `{ sessionId, storeMode, ts, page, productId, eventName: "add_item_to_cart" }` |
+| `remove_item` | Cart | `{ sessionId, storeMode, ts, page, productId, eventName: "remove_item" }` |
+| `checkout_start` | Cart | `{ sessionId, storeMode, ts, page, eventName: "checkout_start" }` |
+| `purchase_complete` | Cart | `{ sessionId, storeMode, ts, page, eventName: "purchase_complete", metadata?: { total: 500 } }` |
+| `search` | Filter/Search | `{ sessionId, storeMode, ts, page, eventName: "search", metadata: { query: "paris" } }` |
+| `filter_for_date` | Filter/Search | `{ sessionId, storeMode, ts, page, eventName: "filter_for_date", metadata: { from: "2025-01-15", to: "2025-01-20" } }` |
+| `filter_for_amenities` | Filter/Search | `{ sessionId, storeMode, ts, page, eventName: "filter_for_amenities", metadata: { amenities: ["wifi", "pool"] } }` |
+| `filter_for_price` | Filter/Search | `{ sessionId, storeMode, ts, page, eventName: "filter_for_price", metadata: { min: 100, max: 500 } }` |
+| `sort_change` | Filter/Search | `{ sessionId, storeMode, ts, page, eventName: "sort_change", metadata: { sort: "price_asc" } }` |
+| `hover_over_title` | Dwell signal | `{ sessionId, storeMode, ts, page, productId?, eventName: "hover_over_title", metadata: { duration: 1500 } }` |
+| `hover_over_paragraph` | Dwell signal | `{ sessionId, storeMode, ts, page, productId?, eventName: "hover_over_paragraph", metadata: { duration: 2000 } }` |
+| `hover_over_link` | Dwell signal | `{ sessionId, storeMode, ts, page, productId?, eventName: "hover_over_link", metadata: { href: "/hotel/products" } }` |
+| `hover_over_button` | Dwell signal | `{ sessionId, storeMode, ts, page, productId?, eventName: "hover_over_button", metadata: { label: "Book Now" } }` |
 
-Check out our [Next.js deployment documentation](https://nextjs.org/docs/app/building-your-application/deploying) for more details.
+## Architecture
+
+### Route Groups
+- `(hotel)` — Hotel mode pages
+- `(airline)` — Airline mode pages
+- `api/*` — API routes (session, pricing, ingest, admin)
+
+### Middleware Flow
+1. Request arrives at Next.js
+2. Session middleware checks for `phantom_session_id` cookie
+3. If missing, `/api/session` mints new session + sets cookie
+4. Store mode (`STORE_MODE` env) determines rendered page variant
+5. Client-side components fetch pricing via `/api/pricing`
+6. User interactions emit events to `/api/ingest` → Kafka

web/package-lock.json

@@ -8,10 +8,10 @@
       "name": "web",
       "version": "0.1.0",
       "dependencies": {
-        "kafkajs": "^2.2.4",
         "next": "16.0.0",
         "react": "19.2.0",
-        "react-dom": "19.2.0"
+        "react-dom": "19.2.0",
+        "zod": "^4.1.12"
       },
       "devDependencies": {
         "@tailwindcss/postcss": "^4",
@@ -1041,15 +1041,6 @@
         "jiti": "lib/jiti-cli.mjs"
       }
     },
-    "node_modules/kafkajs": {
-      "version": "2.2.4",
-      "resolved": "https://registry.npmjs.org/kafkajs/-/kafkajs-2.2.4.tgz",
-      "integrity": "sha512-j/YeapB1vfPT2iOIUn/vxdyKEuhuY2PxMBvf5JWux6iSaukAccrMtXEY/Lb7OvavDhOWME589bpLrEdnVHjfjA==",
-      "license": "MIT",
-      "engines": {
-        "node": ">=14.0.0"
-      }
-    },
     "node_modules/lightningcss": {
       "version": "1.30.2",
       "resolved": "https://registry.npmjs.org/lightningcss/-/lightningcss-1.30.2.tgz",
@@ -1616,6 +1607,15 @@
       "integrity": "sha512-iwDZqg0QAGrg9Rav5H4n0M64c3mkR59cJ6wQp+7C4nI0gsmExaedaYLNO44eT4AtBBwjbTiGPMlt2Md0T9H9JQ==",
       "dev": true,
       "license": "MIT"
+    },
+    "node_modules/zod": {
+      "version": "4.1.12",
+      "resolved": "https://registry.npmjs.org/zod/-/zod-4.1.12.tgz",
+      "integrity": "sha512-JInaHOamG8pt5+Ey8kGmdcAcg3OL9reK8ltczgHTAwNhMys/6ThXHityHxVV2p3fkw/c+MAvBHFVYHFZDmjMCQ==",
+      "license": "MIT",
+      "funding": {
+        "url": "https://github.com/sponsors/colinhacks"
+      }
     }
   }
 }

web/package.json

@@ -8,10 +8,10 @@
     "start": "next start"
   },
   "dependencies": {
-    "kafkajs": "^2.2.4",
     "next": "16.0.0",
     "react": "19.2.0",
-    "react-dom": "19.2.0"
+    "react-dom": "19.2.0",
+    "zod": "^4.1.12"
   },
   "devDependencies": {
     "@tailwindcss/postcss": "^4",

web/src/app/admin/experiments/page.tsx

@@ -0,0 +1,199 @@
+'use client';
+
+import { useEffect, useState } from 'react';
+import { useSession } from '@/hooks/useSession';
+
+type Experiment = {
+  id: string;
+  status: 'active' | 'stopped';
+  sessionIds: string[];
+  createdAt: number;
+};
+
+export default function ExperimentsAdmin() {
+  const { sessionId, isLoading: sessionLoading } = useSession();
+  const [exps, setExps] = useState<Experiment[]>([]);
+  const [loading, setLoading] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+
+  const fetchExps = async () => {
+    try {
+      const res = await fetch('/api/admin/experiments');
+      if (!res.ok) throw new Error(`fetch failed: ${res.status}`);
+      const data = await res.json();
+      setExps(data.experiments || []);
+    } catch (err: any) {
+      setError(err.message);
+    }
+  };
+
+  useEffect(() => {
+    fetchExps();
+  }, []);
+
+  const handleStart = async () => {
+    if (!sessionId) {
+      setError('no session available');
+      return;
+    }
+
+    setLoading(true);
+    setError(null);
+
+    try {
+      const res = await fetch('/api/admin/experiments/start', {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ sessionId }),
+      });
+
+      if (!res.ok) {
+        const data = await res.json();
+        throw new Error(data.error || 'start failed');
+      }
+
+      await fetchExps(); // refresh list
+    } catch (err: any) {
+      setError(err.message);
+    } finally {
+      setLoading(false);
+    }
+  };
+
+  const handleStop = async (expId: string) => {
+    setLoading(true);
+    setError(null);
+
+    try {
+      const res = await fetch('/api/admin/experiments/stop', {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ experimentId: expId }),
+      });
+
+      if (!res.ok) {
+        const data = await res.json();
+        throw new Error(data.error || 'stop failed');
+      }
+
+      await fetchExps(); // refresh list
+    } catch (err: any) {
+      setError(err.message);
+    } finally {
+      setLoading(false);
+    }
+  };
+
+  if (sessionLoading) {
+    return (
+      <div className="flex min-h-screen items-center justify-center bg-zinc-50 dark:bg-black">
+        <p className="text-zinc-600 dark:text-zinc-400">loading session...</p>
+      </div>
+    );
+  }
+
+  return (
+    <div className="min-h-screen bg-zinc-50 px-6 py-12 dark:bg-black">
+      <div className="mx-auto max-w-5xl">
+        <div className="mb-8 flex items-center justify-between">
+          <div>
+            <h1 className="text-3xl font-semibold tracking-tight text-black dark:text-zinc-50">
+              Experiments
+            </h1>
+            <p className="mt-2 text-sm text-zinc-600 dark:text-zinc-400">
+              current session: {sessionId || 'none'}
+            </p>
+          </div>
+          <button
+            onClick={handleStart}
+            disabled={loading || !sessionId}
+            className="rounded-lg bg-black px-4 py-2 text-sm font-medium text-white transition-colors hover:bg-zinc-800 disabled:opacity-50 dark:bg-zinc-50 dark:text-black dark:hover:bg-zinc-200"
+          >
+            {loading ? 'starting...' : 'start experiment'}
+          </button>
+        </div>
+
+        {error && (
+          <div className="mb-4 rounded-lg bg-red-50 p-4 text-sm text-red-800 dark:bg-red-950 dark:text-red-200">
+            {error}
+          </div>
+        )}
+
+        <div className="overflow-hidden rounded-lg border border-zinc-200 bg-white dark:border-zinc-800 dark:bg-zinc-950">
+          <table className="w-full text-left text-sm">
+            <thead className="border-b border-zinc-200 bg-zinc-50 dark:border-zinc-800 dark:bg-zinc-900">
+              <tr>
+                <th className="px-6 py-3 font-medium text-zinc-900 dark:text-zinc-100">
+                  experiment id
+                </th>
+                <th className="px-6 py-3 font-medium text-zinc-900 dark:text-zinc-100">
+                  status
+                </th>
+                <th className="px-6 py-3 font-medium text-zinc-900 dark:text-zinc-100">
+                  session count
+                </th>
+                <th className="px-6 py-3 font-medium text-zinc-900 dark:text-zinc-100">
+                  created
+                </th>
+                <th className="px-6 py-3 font-medium text-zinc-900 dark:text-zinc-100">
+                  action
+                </th>
+              </tr>
+            </thead>
+            <tbody className="divide-y divide-zinc-200 dark:divide-zinc-800">
+              {exps.length === 0 ? (
+                <tr>
+                  <td
+                    colSpan={5}
+                    className="px-6 py-8 text-center text-zinc-500 dark:text-zinc-400"
+                  >
+                    no experiments yet
+                  </td>
+                </tr>
+              ) : (
+                exps.map((exp) => (
+                  <tr
+                    key={exp.id}
+                    className="hover:bg-zinc-50 dark:hover:bg-zinc-900"
+                  >
+                    <td className="px-6 py-4 font-mono text-xs text-zinc-700 dark:text-zinc-300">
+                      {exp.id.slice(0, 8)}...
+                    </td>
+                    <td className="px-6 py-4">
+                      <span
+                        className={`inline-block rounded-full px-2 py-1 text-xs font-medium ${
+                          exp.status === 'active'
+                            ? 'bg-green-100 text-green-800 dark:bg-green-950 dark:text-green-200'
+                            : 'bg-zinc-100 text-zinc-800 dark:bg-zinc-800 dark:text-zinc-200'
+                        }`}
+                      >
+                        {exp.status}
+                      </span>
+                    </td>
+                    <td className="px-6 py-4 text-zinc-700 dark:text-zinc-300">
+                      {exp.sessionIds.length}
+                    </td>
+                    <td className="px-6 py-4 text-zinc-700 dark:text-zinc-300">
+                      {new Date(exp.createdAt).toLocaleString()}
+                    </td>
+                    <td className="px-6 py-4">
+                      {exp.status === 'active' && (
+                        <button
+                          onClick={() => handleStop(exp.id)}
+                          disabled={loading}
+                          className="text-sm font-medium text-red-600 hover:text-red-700 disabled:opacity-50 dark:text-red-400 dark:hover:text-red-300"
+                        >
+                          stop
+                        </button>
+                      )}
+                    </td>
+                  </tr>
+                ))
+              )}
+            </tbody>
+          </table>
+        </div>
+      </div>
+    </div>
+  );
+}

web/src/app/airline/layout.tsx

@@ -0,0 +1,6 @@
+import { ReactNode } from 'react';
+import '@/styles/airline.css';
+
+export default function AirlineLayout({ children }: { children: ReactNode }) {
+  return <div data-mode="airline">{children}</div>;
+}

web/src/app/airline/page.tsx

@@ -0,0 +1,9 @@
+import AirlineHero from '@/components/feats/airline/AirlineHero';
+
+export default function AirlineHome() {
+  return (
+    <main>
+      <AirlineHero />
+    </main>
+  );
+}

web/src/app/airline/products/page.tsx

@@ -0,0 +1,74 @@
+'use client';
+
+import { Navigation } from '@/components/ui';
+import AirlineCard from '@/components/feats/airline/AirlineCard';
+
+type CabinClass = 'economy' | 'premium' | 'business' | 'first';
+type FareRule = 'flexible' | 'standard' | 'basic';
+
+interface Flight {
+  id: string;
+  departure: { time: string; airport: string };
+  arrival: { time: string; airport: string };
+  duration: string;
+  stops: number;
+  cabinClass: CabinClass;
+  fareRule: FareRule;
+  refundable: boolean;
+  basePrice: number;
+}
+
+const genRandomFlights = (): Flight[] => {
+  const airports = ['JFK', 'LAX', 'ORD', 'ATL', 'DFW', 'SFO', 'SEA', 'MIA'];
+  const cabins: CabinClass[] = ['economy', 'premium', 'business', 'first'];
+  const fareRules: FareRule[] = ['flexible', 'standard', 'basic'];
+
+  return Array.from({ length: 12 }, (_, i) => {
+    const depHour = Math.floor(Math.random() * 24);
+    const arrHour = (depHour + Math.floor(Math.random() * 6) + 2) % 24;
+    const stops = Math.random() > 0.6 ? 0 : Math.floor(Math.random() * 2) + 1;
+    const cabin = cabins[Math.floor(Math.random() * cabins.length)];
+    const fareRule = fareRules[Math.floor(Math.random() * fareRules.length)];
+
+    const basePrice = Math.floor(
+      (cabin === 'economy' ? 200 : cabin === 'premium' ? 400 : cabin === 'business' ? 800 : 1500) +
+      Math.random() * 300
+    );
+
+    return {
+      id: `flt-${i}`,
+      departure: {
+        time: `${depHour.toString().padStart(2, '0')}:${Math.floor(Math.random() * 60).toString().padStart(2, '0')}`,
+        airport: airports[Math.floor(Math.random() * airports.length)],
+      },
+      arrival: {
+        time: `${arrHour.toString().padStart(2, '0')}:${Math.floor(Math.random() * 60).toString().padStart(2, '0')}`,
+        airport: airports[Math.floor(Math.random() * airports.length)],
+      },
+      duration: `${Math.floor(Math.random() * 5) + 2}h ${Math.floor(Math.random() * 60)}m`,
+      stops,
+      cabinClass: cabin,
+      fareRule,
+      refundable: Math.random() > 0.7,
+      basePrice,
+    };
+  });
+};
+
+export default function AirlineProducts() {
+  const flights = genRandomFlights();
+
+  return (
+    <>
+      <Navigation />
+      <main className="max-w-7xl mx-auto px-4 py-8">
+        <h1 className="text-3xl font-bold mb-6">Available Flights</h1>
+        <div className="space-y-4">
+          {flights.map((f) => (
+            <AirlineCard key={f.id} flight={f} />
+          ))}
+        </div>
+      </main>
+    </>
+  );
+}

web/src/app/api/admin/experiments/route.ts

@@ -0,0 +1,15 @@
+import { NextResponse } from 'next/server';
+import { getAllExperiments } from '@/lib/sessionStore';
+
+export async function GET() {
+  try {
+    const exps = getAllExperiments();
+    return NextResponse.json({ experiments: exps });
+  } catch (err: any) {
+    console.error('experiments list error:', err);
+    return NextResponse.json(
+      { error: err.message || 'unknown error' },
+      { status: 500 }
+    );
+  }
+}

web/src/app/api/admin/experiments/start/route.ts

@@ -0,0 +1,43 @@
+import { NextRequest, NextResponse } from 'next/server';
+import { randomUUID } from 'crypto';
+import { createExperiment, getSession } from '@/lib/sessionStore';
+
+export async function POST(req: NextRequest) {
+  try {
+    const body = await req.json();
+    const { sessionId } = body;
+
+    if (!sessionId) {
+      return NextResponse.json(
+        { error: 'sessionId required' },
+        { status: 400 }
+      );
+    }
+
+    // verify session exists
+    const session = getSession(sessionId);
+    if (!session) {
+      return NextResponse.json(
+        { error: 'session not found' },
+        { status: 404 }
+      );
+    }
+
+    // generate and create experiment
+    const experimentId = randomUUID();
+    const exp = createExperiment(sessionId, experimentId);
+
+    return NextResponse.json({
+      experimentId: exp.id,
+      sessionId,
+      status: exp.status,
+      createdAt: exp.createdAt,
+    });
+  } catch (err: any) {
+    console.error('experiment start error:', err);
+    return NextResponse.json(
+      { error: err.message || 'unknown error' },
+      { status: 500 }
+    );
+  }
+}

web/src/app/api/admin/experiments/stop/route.ts

@@ -0,0 +1,39 @@
+import { NextRequest, NextResponse } from 'next/server';
+import { stopExperimentById, getExperiment } from '@/lib/sessionStore';
+
+export async function POST(req: NextRequest) {
+  try {
+    const body = await req.json();
+    const { experimentId } = body;
+
+    if (!experimentId) {
+      return NextResponse.json(
+        { error: 'experimentId required' },
+        { status: 400 }
+      );
+    }
+
+    // verify experiment exists
+    const existing = getExperiment(experimentId);
+    if (!existing) {
+      return NextResponse.json(
+        { error: 'experiment not found' },
+        { status: 404 }
+      );
+    }
+
+    // stop the experiment
+    const exp = stopExperimentById(experimentId);
+
+    return NextResponse.json({
+      experimentId: exp!.id,
+      status: exp!.status,
+    });
+  } catch (err: any) {
+    console.error('experiment stop error:', err);
+    return NextResponse.json(
+      { error: err.message || 'unknown error' },
+      { status: 500 }
+    );
+  }
+}

web/src/app/api/ingest/route.ts

@@ -0,0 +1,42 @@
+import { NextRequest, NextResponse } from 'next/server';
+import type { EventBase } from '@/lib/events';
+
+const BACKEND_URL = process.env.BACKEND_URL || 'http://localhost:5000';
+
+export async function POST(req: NextRequest) {
+  try {
+    const body = await req.json();
+
+    const storeMode = process.env.STORE_MODE || 'hotel';
+    const userAgent = req.headers.get('user-agent') || undefined;
+
+    const event: EventBase = {
+      ...body,
+      storeMode,
+      userAgent,
+      ts: body.ts || new Date().toISOString(),
+    };
+
+    const res = await fetch(`${BACKEND_URL}/api/kafka/ingest`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify(event),
+    });
+
+    if (!res.ok) {
+      throw new Error(`Backend returned ${res.status}`);
+    }
+
+    if (process.env.NEXT_PUBLIC_APP_ENV === 'dev') {
+      console.log('[ingest]', event);
+    }
+
+    return NextResponse.json({ success: true });
+  } catch (err: any) {
+    console.error('[ingest error]', err);
+    return NextResponse.json(
+      { error: err.message || 'unknown error' },
+      { status: 500 }
+    );
+  }
+}

web/src/app/api/pricing/route.ts

@@ -0,0 +1,45 @@
+import { NextRequest, NextResponse } from 'next/server';
+
+interface PricingResponse {
+    price: number;
+    currency: string;
+    cachedAt: string;
+}
+
+export async function GET(req: NextRequest) {
+    const { searchParams } = new URL(req.url);
+    const productId = searchParams.get('productId');
+    const sessionId = searchParams.get('sessionId');
+    const experimentId = searchParams.get('experimentId');
+    const storeMode = process.env.NEXT_PUBLIC_STORE_MODE || 'shop';
+
+    // log in dev
+    if (process.env.NODE_ENV === 'development') {
+        console.log('[pricing-api]', {
+            productId,
+            sessionId,
+            experimentId,
+            storeMode,
+            timestamp: new Date().toISOString(),
+        });
+    }
+
+    if (!productId) {
+        return NextResponse.json(
+            { error: 'productId is required' },
+            { status: 400 }
+        );
+    }
+
+    // stub: call external pricing provider (random for now)
+    const basePrice = 100 + Math.random() * 900; // 100-1000 range
+    const price = Math.round(basePrice * 100) / 100;
+
+    const response: PricingResponse = {
+        price,
+        currency: 'EUR',
+        cachedAt: new Date().toISOString(),
+    };
+
+    return NextResponse.json(response);
+}

web/src/app/api/session/route.ts

@@ -0,0 +1,46 @@
+import { NextRequest, NextResponse } from 'next/server';
+import { randomUUID } from 'crypto';
+import { getSession, createSession } from '@/lib/sessionStore';
+
+const COOKIE_NAME = 'phantom_session_id';
+const isProd = process.env.NODE_ENV === 'production';
+
+export async function GET(req: NextRequest) {
+    try {
+        // check for existing session cookie
+        const existingSession = req.cookies.get(COOKIE_NAME)?.value;
+
+        if (existingSession) {
+            const sessionData = getSession(existingSession);
+            return NextResponse.json({
+                sessionId: existingSession,
+                experimentId: sessionData?.experimentId,
+            });
+        }
+
+        // mint new session id
+        const sessionId = randomUUID();
+        createSession(sessionId);
+
+        const res = NextResponse.json({ sessionId, experimentId: undefined });
+
+        // set httpOnly cookie with security flags
+        res.cookies.set({
+            name: COOKIE_NAME,
+            value: sessionId,
+            httpOnly: true,
+            sameSite: 'lax',
+            secure: isProd,
+            path: '/',
+            maxAge: 60 * 60 * 24 * 30, // 30 days
+        });
+
+        return res;
+    } catch (err: any) {
+        console.error('session error:', err);
+        return NextResponse.json(
+            { error: err.message || 'unknown error' },
+            { status: 500 }
+        );
+    }
+}

web/src/app/api/track/route.ts

@@ -1,33 +0,0 @@
-import { NextRequest, NextResponse } from 'next/server';
-import { sendInteractionEvent } from '@/lib/kafka';
-
-export async function POST(req: NextRequest) {
-    try {
-        const body = await req.json();
-        const { sessionId, eventType, targetEl, targetUrl, metadata } = body;
-
-        if (!sessionId || !eventType) {
-            return NextResponse.json(
-                { error: 'sessionId and eventType required' },
-                { status: 400 }
-            );
-        }
-
-        await sendInteractionEvent({
-            sessionId,
-            eventType,
-            targetEl,
-            targetUrl,
-            metadata,
-            ts: Date.now(),
-        });
-
-        return NextResponse.json({ success: true });
-    } catch (err: any) {
-        console.error('track error:', err);
-        return NextResponse.json(
-            { error: err.message || 'unknown error' },
-            { status: 500 }
-        );
-    }
-}

web/src/app/globals.css

@@ -1,8 +1,19 @@
 @import "tailwindcss";
 
+@layer base {
 :root {
   --background: #ffffff;
   --foreground: #171717;
+  --bg-primary: #ffffff;
+  --bg-secondary: #f5f5f5;
+  --text-primary: #333333;
+  --text-secondary: #666666;
+  --spacing-sm: 8px;
+  --spacing-md: 16px;
+  --spacing-lg: 32px;
+  --border-radius: 8px;
+  --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.1);
+}
 }
 
 @theme inline {
@@ -12,6 +23,7 @@
   --font-mono: var(--font-geist-mono);
 }
 
+@layer base {
 @media (prefers-color-scheme: dark) {
   :root {
     --background: #0a0a0a;
@@ -19,8 +31,79 @@
   }
 }
 
+* {
+  box-sizing: border-box;
+  margin: 0;
+  padding: 0;
+}
+
 body {
   background: var(--background);
   color: var(--foreground);
-  font-family: Arial, Helvetica, sans-serif;
+  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
+  line-height: 1.6;
+  -webkit-font-smoothing: antialiased;
+  -moz-osx-font-smoothing: grayscale;
+}
+
+h1, h2, h3, h4, h5, h6 {
+  font-weight: 700;
+  color: var(--text-primary);
+  line-height: 1.2;
+}
+
+h1 { font-size: 2.5rem; }
+h2 { font-size: 2rem; }
+h3 { font-size: 1.5rem; }
+
+button {
+  cursor: pointer;
+  border: none;
+  outline: none;
+  font-family: inherit;
+  transition: all 0.2s ease;
+}
+
+input, select, textarea {
+  font-family: inherit;
+  font-size: 1rem;
+  outline: none;
+}
+}
+
+@layer components {
+.container {
+  max-width: 1200px;
+  margin: 0 auto;
+  padding: 0 var(--spacing-md);
+}
+
+.card {
+  background: var(--bg-primary);
+  border-radius: var(--border-radius);
+  box-shadow: var(--shadow-card);
+  overflow: hidden;
+}
+
+.btn-primary {
+  padding: 12px 24px;
+  font-weight: 600;
+  font-size: 1rem;
+  border-radius: var(--border-radius);
+  transition: all 0.2s ease;
+  background-color: #007aff;
+  color: #ffffff;
+  border: none;
+  cursor: pointer;
+}
+
+.btn-primary:hover {
+  transform: translateY(-1px);
+  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
+  background-color: #0051d5;
+}
+
+.section-spacing {
+  margin-bottom: var(--spacing-lg);
+}
 }

web/src/app/hotel/layout.tsx

@@ -0,0 +1,6 @@
+import { ReactNode } from 'react';
+import '@/styles/hotel.css';
+
+export default function HotelLayout({ children }: { children: ReactNode }) {
+  return <div data-mode="hotel">{children}</div>;
+}

web/src/app/hotel/page.tsx

@@ -0,0 +1,9 @@
+import HotelHero from '@/components/feats/hotel/HotelHero';
+
+export default function HotelHome() {
+  return (
+    <main>
+      <HotelHero />
+    </main>
+  );
+}

web/src/app/hotel/products/page.tsx

@@ -0,0 +1,75 @@
+'use client';
+
+import { Navigation } from '@/components/ui';
+import HotelCard from '@/components/feats/hotel/HotelCard';
+
+interface Hotel {
+  id: string;
+  name: string;
+  roomType: string;
+  checkIn: string;
+  checkOut: string;
+  amenities: string[];
+  refundable: boolean;
+  pricePerNight: number;
+  nights: number;
+}
+
+const genRandomHotels = (): Hotel[] => {
+  const names = [
+    'Grand Plaza Hotel',
+    'Seaside Resort',
+    'Downtown Suites',
+    'Mountain View Lodge',
+    'City Center Inn',
+    'Luxury Beach Resort',
+    'Urban Boutique Hotel',
+    'Garden View Hotel',
+  ];
+  const roomTypes = ['Standard Room', 'Deluxe Room', 'Suite', 'Executive Suite', 'Premium Room'];
+  const amenities = ['wifi', 'pool', 'gym', 'parking', 'breakfast', 'spa'];
+
+  return Array.from({ length: 10 }, (_, i) => {
+    const nights = Math.floor(Math.random() * 5) + 1;
+    const basePrice = Math.floor(80 + Math.random() * 220);
+    const selectedAmenities = amenities
+      .sort(() => Math.random() - 0.5)
+      .slice(0, Math.floor(Math.random() * 3) + 2);
+
+    const today = new Date();
+    const checkInDate = new Date(today);
+    checkInDate.setDate(today.getDate() + Math.floor(Math.random() * 10));
+    const checkOutDate = new Date(checkInDate);
+    checkOutDate.setDate(checkInDate.getDate() + nights);
+
+    return {
+      id: `htl-${i}`,
+      name: names[i % names.length],
+      roomType: roomTypes[Math.floor(Math.random() * roomTypes.length)],
+      checkIn: checkInDate.toLocaleDateString('en-US', { month: 'short', day: 'numeric' }),
+      checkOut: checkOutDate.toLocaleDateString('en-US', { month: 'short', day: 'numeric' }),
+      amenities: selectedAmenities,
+      refundable: Math.random() > 0.5,
+      pricePerNight: basePrice,
+      nights,
+    };
+  });
+};
+
+export default function HotelProducts() {
+  const hotels = genRandomHotels();
+
+  return (
+    <>
+      <Navigation />
+      <main className="max-w-7xl mx-auto px-4 py-8">
+        <h1 className="text-3xl font-bold mb-6">Available Hotels</h1>
+        <div className="space-y-4">
+          {hotels.map((h) => (
+            <HotelCard key={h.id} hotel={h} />
+          ))}
+        </div>
+      </main>
+    </>
+  );
+}

web/src/components/feats/airline/AirlineCard.tsx

@@ -0,0 +1,87 @@
+'use client';
+
+import type { EventName } from '@/lib/events';
+import { useHoverTracking } from '@/hooks/useHoverTracking';
+import PriceDisplay from '@/components/ui/PriceDisplay';
+
+const dispatchInteraction = (eventName: EventName, productId?: string, metadata?: Record<string, unknown>) => {
+    const e = new CustomEvent('definedInteraction', {
+        detail: { eventName, productId, metadata },
+    });
+    document.dispatchEvent(e);
+};
+
+type CabinClass = 'economy' | 'premium' | 'business' | 'first';
+type FareRule = 'flexible' | 'standard' | 'basic';
+
+interface Flight {
+    id: string;
+    departure: { time: string; airport: string };
+    arrival: { time: string; airport: string };
+    duration: string;
+    stops: number;
+    cabinClass: CabinClass;
+    fareRule: FareRule;
+    refundable: boolean;
+    basePrice: number;
+}
+
+export default function AirlineCard({ flight }: { flight: Flight }) {
+    const durationRef = useHoverTracking({
+        eventName: 'hover_over_title',
+        productId: flight.id,
+        metadata: { elementText: flight.duration },
+    });
+
+    const priceRef = useHoverTracking({
+        eventName: 'hover_over_paragraph',
+        productId: flight.id,
+        metadata: { elementText: 'price' },
+    });
+
+    const handleCardClick = () => {
+        dispatchInteraction('view_item_page', flight.id, {
+            cabinClass: flight.cabinClass,
+            fareRule: flight.fareRule,
+            price: flight.basePrice,
+        });
+    };
+
+    return (
+        <div
+            className="flight-card cursor-pointer"
+            onClick={handleCardClick}
+        >
+            <div className="flight-timing">
+                <div className="flight-time">{flight.departure.time}</div>
+                <div className="flight-airport">{flight.departure.airport}</div>
+            </div>
+
+            <div className="flight-route">
+                <div ref={durationRef} className="flight-duration">{flight.duration}</div>
+                <div className="flight-stops">
+                    {flight.stops === 0 ? 'Direct' : `${flight.stops} stop${flight.stops > 1 ? 's' : ''}`}
+                </div>
+            </div>
+
+            <div className="flight-timing">
+                <div className="flight-time">{flight.arrival.time}</div>
+                <div className="flight-airport">{flight.arrival.airport}</div>
+            </div>
+
+            <div className="flight-pricing">
+                <div className="fare-class capitalize mb-2">{flight.cabinClass}</div>
+                <div className="text-sm text-[var(--text-secondary)] mb-2 capitalize">{flight.fareRule}</div>
+                {flight.refundable && (
+                    <div className="badge-value text-xs mb-2">Refundable</div>
+                )}
+                <div ref={priceRef}>
+                    <PriceDisplay
+                        productId={flight.id}
+                        className="fare-price"
+                    />
+                </div>
+            </div>
+        </div>
+    );
+}

web/src/components/feats/airline/AirlineHero.tsx

@@ -0,0 +1,156 @@
+'use client';
+
+import { useState, FormEvent } from 'react';
+import { Button, Label, Input, DateInput, RadioGroup, Dropdown, DropdownCounter } from '@/components/ui';
+
+type TripType = 'roundtrip' | 'oneway' | 'multicity';
+
+const PlaneIcon = () => (
+  <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M12 19l9 2-9-18-9 18 9-2zm0 0v-8" />
+  </svg>
+);
+
+const LocationIcon = () => (
+  <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M17.657 16.657L13.414 20.9a1.998 1.998 0 01-2.827 0l-4.244-4.243a8 8 0 1111.314 0z" />
+    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M15 11a3 3 0 11-6 0 3 3 0 016 0z" />
+  </svg>
+);
+
+export default function AirlineHero() {
+  const [tripType, setTripType] = useState<TripType>('roundtrip');
+  const [origin, setOrigin] = useState('');
+  const [destination, setDestination] = useState('');
+  const [departDate, setDepartDate] = useState('');
+  const [returnDate, setReturnDate] = useState('');
+  const [passengers, setPassengers] = useState({ adults: 1, children: 0, infants: 0 });
+
+  const handleSearch = (e: FormEvent) => {
+    e.preventDefault();
+    console.log({ tripType, origin, destination, departDate, returnDate, passengers });
+  };
+
+  const totalPax = passengers.adults + passengers.children + passengers.infants;
+
+  return (
+    <div className="hero-section min-h-[70vh] flex items-center justify-center">
+      <div className="w-full max-w-5xl px-4">
+        <div className="text-center mb-8">
+          <h1 className="text-4xl md:text-5xl font-bold mb-4">
+            Book flights at the best prices
+          </h1>
+          <p className="text-lg">
+            Compare hundreds of airlines and find the perfect flight for your journey
+          </p>
+        </div>
+
+        <div className="search-form">
+          <form onSubmit={handleSearch}>
+            <div className="mb-6">
+              <RadioGroup
+                name="tripType"
+                value={tripType}
+                onChange={setTripType}
+                options={[
+                  { value: 'roundtrip', label: 'Round-trip' },
+                  { value: 'oneway', label: 'One-way' },
+                  { value: 'multicity', label: 'Multi-city' },
+                ]}
+              />
+            </div>
+
+            <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-4 gap-4">
+              <div>
+                <Label htmlFor="origin">From</Label>
+                <Input
+                  type="text"
+                  id="origin"
+                  value={origin}
+                  onChange={(e) => setOrigin(e.target.value)}
+                  placeholder="Airport or city"
+                  icon={<PlaneIcon />}
+                  required
+                />
+              </div>
+
+              <div>
+                <Label htmlFor="destination">To</Label>
+                <Input
+                  type="text"
+                  id="destination"
+                  value={destination}
+                  onChange={(e) => setDestination(e.target.value)}
+                  placeholder="Airport or city"
+                  icon={<LocationIcon />}
+                  required
+                />
+              </div>
+
+              <div>
+                <Label htmlFor="departDate">Departure</Label>
+                <DateInput
+                  id="departDate"
+                  value={departDate}
+                  onChange={(e) => setDepartDate(e.target.value)}
+                  required
+                />
+              </div>
+
+              <div>
+                <Label htmlFor="returnDate">Return</Label>
+                {tripType === 'roundtrip' ? (
+                  <DateInput
+                    id="returnDate"
+                    value={returnDate}
+                    onChange={(e) => setReturnDate(e.target.value)}
+                    required
+                  />
+                ) : (
+                  <DateInput id="returnDate" disabled />
+                )}
+              </div>
+            </div>
+
+            <div className="grid grid-cols-4 sm:grid-cols-3 lg:grid-cols-4 gap-4 mt-4">
+              <div className="sm:col-span-1 lg:col-span-1">
+                <Label htmlFor="passengers">Passengers</Label>
+                <Dropdown label={`${totalPax} ${totalPax === 1 ? 'passenger' : 'passengers'}`}>
+                  <DropdownCounter
+                    label="Adults"
+                    sublabel="12+ years"
+                    value={passengers.adults}
+                    min={1}
+                    onChange={(v) => setPassengers({ ...passengers, adults: v })}
+                  />
+                  <DropdownCounter
+                    label="Children"
+                    sublabel="2-11 years"
+                    value={passengers.children}
+                    onChange={(v) => setPassengers({ ...passengers, children: v })}
+                  />
+                  <DropdownCounter
+                    label="Infants"
+                    sublabel="Under 2"
+                    value={passengers.infants}
+                    onChange={(v) => setPassengers({ ...passengers, infants: v })}
+                  />
+                </Dropdown>
+              </div>
+            </div>
+
+            <div className="mt-6">
+              <Button type="submit" fullWidth>
+                Search Flights
+              </Button>
+            </div>
+          </form>
+        </div>
+
+        <div className="mt-6 text-center text-sm">
+          <p>Direct flights available · Flexible booking · Compare 500+ airlines worldwide</p>
+        </div>
+      </div>
+    </div>
+  );
+}

web/src/components/feats/hotel/HotelCard.tsx

@@ -0,0 +1,98 @@
+'use client';
+
+import type { EventName } from '@/lib/events';
+import { useHoverTracking } from '@/hooks/useHoverTracking';
+import PriceDisplay from '@/components/ui/PriceDisplay';
+
+const dispatchInteraction = (eventName: EventName, productId?: string, metadata?: Record<string, unknown>) => {
+    const e = new CustomEvent('definedInteraction', {
+        detail: { eventName, productId, metadata },
+    });
+    document.dispatchEvent(e);
+};
+
+interface Hotel {
+    id: string;
+    name: string;
+    roomType: string;
+    checkIn: string;
+    checkOut: string;
+    amenities: string[];
+    refundable: boolean;
+    pricePerNight: number;
+    nights: number;
+}
+
+const AmenityIcon = ({ name }: { name: string }) => {
+    const iconMap: Record<string, string> = {
+        wifi: 'Wi-Fi',
+        pool: 'Pool',
+        gym: 'Gym',
+        parking: 'Parking',
+        breakfast: 'Breakfast',
+        spa: 'Spa',
+    };
+    return <span className="feature-tag">{iconMap[name.toLowerCase()] || name}</span>;
+};
+
+export default function HotelCard({ hotel }: { hotel: Hotel }) {
+    const titleRef = useHoverTracking({
+        eventName: 'hover_over_title',
+        productId: hotel.id,
+        metadata: { elementText: hotel.name },
+    });
+
+    const priceRef = useHoverTracking({
+        eventName: 'hover_over_paragraph',
+        productId: hotel.id,
+        metadata: { elementText: 'price' },
+    });
+
+    const handleCardClick = () => {
+        dispatchInteraction('view_item_page', hotel.id, {
+            roomType: hotel.roomType,
+            price: hotel.pricePerNight,
+            nights: hotel.nights,
+        });
+    };
+
+    return (
+        <div
+            className="hotel-card cursor-pointer"
+            onClick={handleCardClick}
+        >
+            <div className="hotel-image bg-gray-200 flex items-center justify-center">
+                <span className="text-gray-400 text-sm">Image</span>
+            </div>
+
+            <div className="hotel-info">
+                <h3 ref={titleRef} className="hotel-name">{hotel.name}</h3>
+                <div className="hotel-location text-sm mb-2">{hotel.roomType}</div>
+                <div className="text-sm text-[var(--text-secondary)] mb-2">
+                    {hotel.checkIn} - {hotel.checkOut}
+                </div>
+                <div className="hotel-features">
+                    {hotel.amenities.map((a) => (
+                        <AmenityIcon key={a} name={a} />
+                    ))}
+                </div>
+                {hotel.refundable && (
+                    <div className="free-cancellation mt-2">Free cancellation</div>
+                )}
+            </div>
+
+            <div className="hotel-pricing">
+                <div ref={priceRef}>
+                    <PriceDisplay
+                        productId={hotel.id}
+                        className="price-wrapper"
+                        perNight
+                    />
+                </div>
+                <div className="text-xs text-[var(--text-secondary)] mt-1">
+                    Total for {hotel.nights} night{hotel.nights > 1 ? 's' : ''}
+                </div>
+            </div>
+        </div>
+    );
+}

web/src/components/feats/hotel/HotelHero.tsx

@@ -0,0 +1,103 @@
+'use client';
+
+import { useState, FormEvent } from 'react';
+import { Button, Label, Input, DateInput, Dropdown, DropdownCounter } from '@/components/ui';
+
+const LocationIcon = () => (
+  <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M17.657 16.657L13.414 20.9a1.998 1.998 0 01-2.827 0l-4.244-4.243a8 8 0 1111.314 0z" />
+    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M15 11a3 3 0 11-6 0 3 3 0 016 0z" />
+  </svg>
+);
+
+export default function HotelHero() {
+  const [destination, setDestination] = useState('');
+  const [checkIn, setCheckIn] = useState('');
+  const [checkOut, setCheckOut] = useState('');
+  const [guests, setGuests] = useState({ adults: 2, rooms: 1 });
+
+  const handleSearch = (e: FormEvent) => {
+    e.preventDefault();
+    console.log({ destination, checkIn, checkOut, guests });
+  };
+
+  return (
+    <div className="hero-section min-h-[70vh] flex items-center justify-center">
+      <div className="w-full max-w-4xl px-4">
+        <div className="text-center mb-8">
+          <h1 className="text-4xl md:text-5xl font-bold mb-4">
+            Find your perfect stay
+          </h1>
+          <p className="text-lg">
+            Search hotels, compare prices, and book with confidence
+          </p>
+        </div>
+
+        <form onSubmit={handleSearch} className="search-form">
+          <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-4 gap-4">
+            <div className="sm:col-span-2">
+              <Label htmlFor="destination">Where to?</Label>
+              <Input
+                type="text"
+                id="destination"
+                value={destination}
+                onChange={(e) => setDestination(e.target.value)}
+                placeholder="City, hotel, or landmark"
+                icon={<LocationIcon />}
+                required
+              />
+            </div>
+
+            <div>
+              <Label htmlFor="checkIn">Check-in</Label>
+              <DateInput
+                id="checkIn"
+                value={checkIn}
+                onChange={(e) => setCheckIn(e.target.value)}
+                required
+              />
+            </div>
+
+            <div>
+              <Label htmlFor="checkOut">Check-out</Label>
+              <DateInput
+                id="checkOut"
+                value={checkOut}
+                onChange={(e) => setCheckOut(e.target.value)}
+                required
+              />
+            </div>
+
+            <div className="sm:col-span-2 lg:col-span-4">
+              <Label htmlFor="guests">Guests & Rooms</Label>
+              <Dropdown label={`${guests.adults} ${guests.adults === 1 ? 'adult' : 'adults'}, ${guests.rooms} ${guests.rooms === 1 ? 'room' : 'rooms'}`}>
+                <DropdownCounter
+                  label="Adults"
+                  value={guests.adults}
+                  min={1}
+                  onChange={(v) => setGuests({ ...guests, adults: v })}
+                />
+                <DropdownCounter
+                  label="Rooms"
+                  value={guests.rooms}
+                  min={1}
+                  onChange={(v) => setGuests({ ...guests, rooms: v })}
+                />
+              </Dropdown>
+            </div>
+
+            <div className="sm:col-span-2 lg:col-span-4">
+              <Button type="submit" fullWidth>
+                Search Hotels
+              </Button>
+            </div>
+          </div>
+        </form>
+
+        <div className="mt-6 text-center text-sm">
+          <p>Over 2 million hotels worldwide · Best price guarantee · Free cancellation on most bookings</p>
+        </div>
+      </div>
+    </div>
+  );
+}

web/src/components/ui/Button.tsx

@@ -0,0 +1,20 @@
+import { ReactNode, ButtonHTMLAttributes } from 'react';
+
+type BtnVariant = 'primary' | 'secondary';
+
+interface BtnProps extends ButtonHTMLAttributes<HTMLButtonElement> {
+  variant?: BtnVariant;
+  children: ReactNode;
+  fullWidth?: boolean;
+}
+
+export default function Button({ variant = 'primary', children, fullWidth, className = '', ...props }: BtnProps) {
+  const baseClass = variant === 'primary' ? 'btn-primary' : 'btn-secondary';
+  const widthClass = fullWidth ? 'w-full' : '';
+
+  return (
+    <button className={`${baseClass} ${widthClass} ${className}`.trim()} {...props}>
+      {children}
+    </button>
+  );
+}

web/src/components/ui/DateInput.tsx

@@ -0,0 +1,7 @@
+import { InputHTMLAttributes } from 'react';
+
+interface DateInpProps extends Omit<InputHTMLAttributes<HTMLInputElement>, 'type'> {}
+
+export default function DateInput({ className = '', ...props }: DateInpProps) {
+  return <input type="date" className={`input-field ${className}`.trim()} {...props} />;
+}

web/src/components/ui/Dropdown.tsx

@@ -0,0 +1,83 @@
+'use client';
+
+import { ReactNode, useState, useRef, useEffect } from 'react';
+
+interface DropdownProps {
+  label: string;
+  children: ReactNode;
+}
+
+export default function Dropdown({ label, children }: DropdownProps) {
+  const [open, setOpen] = useState(false);
+  const ref = useRef<HTMLDivElement>(null);
+
+  useEffect(() => {
+    const handleClick = (e: MouseEvent) => {
+      if (ref.current && !ref.current.contains(e.target as Node)) {
+        setOpen(false);
+      }
+    };
+
+    document.addEventListener('mousedown', handleClick);
+    return () => document.removeEventListener('mousedown', handleClick);
+  }, []);
+
+  return (
+    <div className="relative" ref={ref}>
+      <button
+        type="button"
+        onClick={() => setOpen(!open)}
+        className="input-field flex justify-between items-center w-full"
+      >
+        <span>{label}</span>
+        <svg className="w-5 h-5 text-gray-400" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+          <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M19 9l-7 7-7-7" />
+        </svg>
+      </button>
+      {open && (
+        <div className="absolute z-10 mt-2 w-full bg-white border border-gray-200 rounded-lg shadow-lg p-4">
+          {children}
+        </div>
+      )}
+    </div>
+  );
+}
+
+interface CounterProps {
+  label: string;
+  sublabel?: string;
+  value: number;
+  min?: number;
+  max?: number;
+  onChange: (val: number) => void;
+}
+
+export function DropdownCounter({ label, sublabel, value, min = 0, max = 99, onChange }: CounterProps) {
+  return (
+    <div className="flex justify-between items-center py-3 border-b border-gray-100 last:border-b-0">
+      <div className="flex flex-col">
+        <span className="text-sm font-medium text-gray-900">{label}</span>
+        {sublabel && <span className="text-xs text-gray-500 mt-0.5">{sublabel}</span>}
+      </div>
+      <div className="flex items-center gap-3">
+        <button
+          type="button"
+          onClick={() => onChange(Math.max(min, value - 1))}
+          disabled={value <= min}
+          className="w-9 h-9 rounded-full border-2 border-gray-300 flex items-center justify-center hover:border-blue-500 hover:bg-blue-50 disabled:opacity-40 disabled:cursor-not-allowed disabled:hover:border-gray-300 disabled:hover:bg-transparent transition-colors text-lg font-medium text-gray-700"
+        >
+          −
+        </button>
+        <span className="w-10 text-center font-semibold text-gray-900">{value}</span>
+        <button
+          type="button"
+          onClick={() => onChange(Math.min(max, value + 1))}
+          disabled={value >= max}
+          className="w-9 h-9 rounded-full border-2 border-gray-300 flex items-center justify-center hover:border-blue-500 hover:bg-blue-50 disabled:opacity-40 disabled:cursor-not-allowed disabled:hover:border-gray-300 disabled:hover:bg-transparent transition-colors text-lg font-medium text-gray-700"
+        >
+          +
+        </button>
+      </div>
+    </div>
+  );
+}

web/src/components/ui/Input.tsx

@@ -0,0 +1,29 @@
+import { InputHTMLAttributes, ReactNode } from 'react';
+
+interface InpProps extends InputHTMLAttributes<HTMLInputElement> {
+    icon?: ReactNode;
+}
+
+export default function Input({ icon, className = '', style, ...props }: InpProps) {
+    const padClass = icon ? 'pl-10' : '';
+    // Fallback if a custom CSS rule still overrides Tailwind
+    const mergedStyle = icon ? { paddingInlineStart: '2.5rem', ...style } : style;
+
+    return (
+        <div className="relative">
+            {icon && (
+                <div
+                    aria-hidden
+                    className="pointer-events-none absolute inset-y-0 left-0 flex items-center pl-3 text-gray-400 z-10"
+                >
+                    {icon}
+                </div>
+            )}
+            <input
+                className={`input-field ${className} ${padClass}`}
+                style={mergedStyle}
+                {...props}
+            />
+        </div>
+    );
+}

web/src/components/ui/Label.tsx

@@ -0,0 +1,13 @@
+import { ReactNode, LabelHTMLAttributes } from 'react';
+
+interface LblProps extends LabelHTMLAttributes<HTMLLabelElement> {
+  children: ReactNode;
+}
+
+export default function Label({ children, className = '', ...props }: LblProps) {
+  return (
+    <label className={`block text-sm font-medium mb-2 ${className}`.trim()} {...props}>
+      {children}
+    </label>
+  );
+}

web/src/components/ui/Navigation.tsx

@@ -0,0 +1,48 @@
+'use client';
+
+import Link from 'next/link';
+import { usePathname } from 'next/navigation';
+import type { EventName } from '@/lib/events';
+
+const dispatchInteraction = (eventName: EventName, metadata?: Record<string, unknown>) => {
+  const e = new CustomEvent('definedInteraction', {
+    detail: { eventName, metadata },
+  });
+  document.dispatchEvent(e);
+};
+
+const NavLink = ({ href, children }: { href: string; children: React.ReactNode }) => {
+  const path = usePathname();
+  const isActive = path === href;
+
+  return (
+    <Link
+      href={href}
+      className={`px-4 py-2 rounded-md transition-colors ${
+        isActive
+          ? 'bg-[var(--accent-primary)] text-white font-semibold'
+          : 'hover:bg-[var(--accent-primary-light)] text-[var(--text-primary)]'
+      }`}
+    >
+      {children}
+    </Link>
+  );
+};
+
+export default function Navigation() {
+  return (
+    <nav className="bg-[var(--bg-primary)] border-b border-gray-200 shadow-sm">
+      <div className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8">
+        <div className="flex justify-between h-16">
+          <div className="flex items-center space-x-1">
+            <NavLink href="/">Home</NavLink>
+            <NavLink href="/products">Products</NavLink>
+            <NavLink href="/search">Search</NavLink>
+            <NavLink href="/cart">Cart</NavLink>
+            <NavLink href="/checkout">Checkout</NavLink>
+          </div>
+        </div>
+      </div>
+    </nav>
+  );
+}

web/src/components/ui/PriceDisplay.tsx

@@ -0,0 +1,136 @@
+'use client';
+
+import { useEffect, useState, useRef } from 'react';
+
+interface PriceDisplayProps {
+    productId: string;
+    className?: string;
+    perNight?: boolean;
+}
+
+interface PricingData {
+    price: number;
+    currency: string;
+    cachedAt: string;
+}
+
+interface SessionData {
+    sessionId: string;
+    experimentId?: string;
+}
+
+const fetchSession = async (): Promise<SessionData> => {
+    try {
+        const res = await fetch('/api/session');
+        const data = await res.json();
+        return {
+            sessionId: data.sessionId || '',
+            experimentId: data.experimentId || '',
+        };
+    } catch (err) {
+        console.error('failed to fetch session:', err);
+        return { sessionId: '', experimentId: '' };
+    }
+};
+
+const formatPrice = (price: number, currency: string) => {
+    return new Intl.NumberFormat('en-US', { // like an std localization
+        style: 'currency',
+        currency,
+    }).format(price);
+};
+
+const isCacheStale = (cachedAt: string, thresholdMs = 60000) => {
+    const cacheTime = new Date(cachedAt).getTime();
+    const now = Date.now();
+    return now - cacheTime > thresholdMs;
+};
+
+export default function PriceDisplay({
+    productId,
+    className = '',
+    perNight = false,
+}: PriceDisplayProps) {
+    const sessionRef = useRef<SessionData | null>(null);
+    const [data, setData] = useState<PricingData | null>(null);
+    const [loading, setLoading] = useState(true);
+    const [error, setError] = useState<string | null>(null);
+
+    useEffect(() => {
+        const initAndFetch = async () => {
+            setLoading(true);
+            setError(null);
+
+            try {
+                // fetch session if not already loaded
+                if (!sessionRef.current) {
+                    sessionRef.current = await fetchSession();
+                }
+
+                const { sessionId, experimentId } = sessionRef.current;
+
+                if (!sessionId) {
+                    setError('Invalid session');
+                    setLoading(false);
+                    return;
+                }
+
+                const params = new URLSearchParams({
+                    productId,
+                    sessionId,
+                    experimentId: experimentId || '',
+                });
+
+                const res = await fetch(`/api/pricing?${params.toString()}`);
+
+                if (!res.ok) {
+                    throw new Error(`Failed to fetch price: ${res.status}`);
+                }
+
+                const pricingData: PricingData = await res.json();
+                setData(pricingData);
+            } catch (err) {
+                setError(err instanceof Error ? err.message : 'Unknown error');
+            } finally {
+                setLoading(false);
+            }
+        };
+
+        initAndFetch();
+    }, [productId]);
+
+    if (loading) {
+        return (
+            <div className={`price-loading ${className}`}>
+                <div className="spinner-border animate-spin inline-block w-4 h-4 border-2 rounded-full" role="status">
+                    <span className="sr-only">Loading...</span>
+                </div>
+            </div>
+        );
+    }
+
+    if (error || !data) {
+        return (
+            <div className={`price-error ${className}`}>
+                <span className="text-red-500 text-sm">Price unavailable</span>
+            </div>
+        );
+    }
+
+    const isStale = isCacheStale(data.cachedAt);
+    const formattedPrice = formatPrice(data.price, data.currency);
+
+    return (
+        <div className={`price-display ${className}`}>
+            <div className="price-amount">
+                {formattedPrice}
+                {perNight && <span className="text-xs ml-1">/night</span>}
+            </div>
+            {isStale && (
+                <span className="price-stale text-xs text-yellow-600" title={`Cached at ${data.cachedAt}`}>
+                    prices may be outdated
+                </span>
+            )}
+        </div>
+    );
+}

web/src/components/ui/RadioGroup.tsx

@@ -0,0 +1,33 @@
+'use client';
+
+interface RadioOpt<T extends string> {
+  value: T;
+  label: string;
+}
+
+interface RadioGrpProps<T extends string> {
+  name: string;
+  options: RadioOpt<T>[];
+  value: T;
+  onChange: (val: T) => void;
+}
+
+export default function RadioGroup<T extends string>({ name, options, value, onChange }: RadioGrpProps<T>) {
+  return (
+    <div className="flex gap-4">
+      {options.map((opt) => (
+        <label key={opt.value} className="flex items-center cursor-pointer">
+          <input
+            type="radio"
+            name={name}
+            value={opt.value}
+            checked={value === opt.value}
+            onChange={(e) => onChange(e.target.value as T)}
+            className="mr-2"
+          />
+          <span className="text-sm">{opt.label}</span>
+        </label>
+      ))}
+    </div>
+  );
+}

web/src/components/ui/index.ts

@@ -0,0 +1,7 @@
+export { default as Button } from './Button';
+export { default as Label } from './Label';
+export { default as Input } from './Input';
+export { default as DateInput } from './DateInput';
+export { default as RadioGroup } from './RadioGroup';
+export { default as Dropdown, DropdownCounter } from './Dropdown';
+export { default as Navigation } from './Navigation';

web/src/hooks/useHoverTracking.ts

@@ -0,0 +1,63 @@
+import { useCallback, useRef } from 'react';
+import type { EventName } from '@/lib/events';
+
+const dispatchInteraction = (
+    eventName: EventName,
+    productId?: string,
+    metadata?: Record<string, unknown>
+) => {
+    const e = new CustomEvent('definedInteraction', {
+        detail: { eventName, productId, metadata },
+    });
+    document.dispatchEvent(e);
+};
+
+interface UseHoverTrackingOptions {
+    eventName: EventName;
+    productId?: string;
+    metadata?: Record<string, unknown>;
+    threshold?: number; // ms, default 1500 or NEXT_PUBLIC_HOVER_THRESHOLD
+}
+
+export const useHoverTracking = (options: UseHoverTrackingOptions) => {
+    const defaultThreshold = process.env.NEXT_PUBLIC_HOVER_THRESHOLD
+        ? parseInt(process.env.NEXT_PUBLIC_HOVER_THRESHOLD, 10)
+        : 1500;
+    const { eventName, productId, metadata, threshold = defaultThreshold } = options;
+    const timerRef = useRef<NodeJS.Timeout | undefined>(undefined);
+    const startRef = useRef<number | undefined>(undefined);
+
+    return useCallback((node: HTMLElement | null) => {
+        if (!node) {
+            if (timerRef.current) clearTimeout(timerRef.current);
+            return;
+        }
+
+        const onEnter = () => {
+            startRef.current = Date.now();
+            timerRef.current = setTimeout(() => {
+                const dwellTime = Date.now() - startRef.current!;
+                dispatchInteraction(eventName, productId, {
+                    ...metadata,
+                    dwellTime,
+                });
+            }, threshold);
+        };
+
+        const onLeave = () => {
+            if (timerRef.current) {
+                clearTimeout(timerRef.current);
+                timerRef.current = undefined;
+            }
+        };
+
+        node.addEventListener('mouseenter', onEnter);
+        node.addEventListener('mouseleave', onLeave);
+
+        return () => {
+            node.removeEventListener('mouseenter', onEnter);
+            node.removeEventListener('mouseleave', onLeave);
+            if (timerRef.current) clearTimeout(timerRef.current);
+        };
+    }, [eventName, productId, metadata, threshold]);
+};

web/src/hooks/useInteractionTracking.ts

@@ -1,28 +1,27 @@
-import { useEffect, useRef } from 'react';
+import { useEffect, useRef, useState } from 'react';
 import '@/lib/experiments' // ensure experiments lib is loaded
+import type { EventName } from '@/lib/events';
 
-const genSessionId = () => {
+const fetchSessionId = async (): Promise<string> => {
-    if (typeof window === 'undefined') return '';
+  try {
-    let sid = sessionStorage.getItem('phantom_session_id');
+    const res = await fetch('/api/session');
-    if (!sid) {
+    const data = await res.json();
-        sid = `${Date.now()}-${Math.random().toString(36).slice(2)}`;
+    return data.sessionId || '';
-        sessionStorage.setItem('phantom_session_id', sid);
+  } catch (err) {
-        // TODO: when creating new id send to exepriemtn tracking db
+    console.error('failed to fetch session:', err);
-        // match between sesion-id and experiment-id for this session
+    return '';
-        // so that we can identify all interactions aligning with a specific experiment goal.
   }
-    return sid;
 };
 
 const track = async (ev: {
   sessionId: string;
-    eventType: string;
+  eventName: EventName;
-    targetEl?: string;
+  page: string;
-    targetUrl?: string;
+  productId?: string;
-    metadata?: Record<string, any>;
+  metadata?: Record<string, unknown>;
 }) => {
   try {
-        await fetch('/api/track', {
+    await fetch('/api/ingest', {
       method: 'POST',
       headers: { 'Content-Type': 'application/json' },
       body: JSON.stringify(ev),
@@ -34,84 +33,54 @@ const track = async (ev: {
 
 export const useInteractionTracking = () => {
     const sidRef = useRef<string>('');
+    const [ready, setReady] = useState(false);
 
     useEffect(() => {
-        sidRef.current = genSessionId();
+        // fetch session id from httpOnly cookie via API
-
+        fetchSessionId().then((sid) => {
-        const handleClick = (e: MouseEvent) => {
+            sidRef.current = sid;
-            const tgt = e.target as HTMLElement;
+            setReady(true);
-            track({
-                sessionId: sidRef.current,
-                eventType: 'click',
-                targetEl: tgt.tagName,
-                targetUrl: tgt instanceof HTMLAnchorElement ? tgt.href : undefined,
-                metadata: {
-                    x: e.clientX,
-                    y: e.clientY,
-                    path: window.location.pathname,
-                },
         });
-        };
-
-        const handleScroll = () => {
-            track({
-                sessionId: sidRef.current,
-                eventType: 'scroll',
-                metadata: {
-                    scrollY: window.scrollY,
-                    path: window.location.pathname,
-                },
-            });
-        };
 
         const handlePageView = () => {
+            if (!sidRef.current) return;
+            const page = window.location.pathname;
             track({
                 sessionId: sidRef.current,
-                eventType: 'pageview',
+                eventName: 'page_view',
+                page,
                 metadata: {
-                    path: window.location.pathname,
                     referrer: document.referrer,
                 },
             });
         };
 
-        enum DefinedInteractions {
+        // called for canonical events dispatched via custom events
-            ADD_TO_CART = 'add_to_cart',
+        const handleDefinedInteraction = (e: Event) => {
-            PURCHASE = 'purchase',
+            if (!sidRef.current) return;
-        }
+            const customEvent = e as CustomEvent<{
-
+                eventName: EventName;
-        // called when clicking on "Add to Cart" button or "Purchase" button
+                productId?: string;
-        const handleDefinedInteraction = (
+                metadata?: Record<string, unknown>;
-            interactionType: DefinedInteractions,
+            }>;
-            metadata?: Record<string, any>
+            const page = window.location.pathname;
-        ) => {
             track({
                 sessionId: sidRef.current,
-                eventType: interactionType,
+                eventName: customEvent.detail.eventName,
-                metadata: {
+                page,
-                    path: window.location.pathname,
+                productId: customEvent.detail.productId,
-                    ...metadata,
+                metadata: customEvent.detail.metadata,
-                },
             });
         };
 
+        // wait for session to be ready before tracking
+        if (!ready) return;
 
         handlePageView();
-        document.addEventListener('click', handleClick);
+        document.addEventListener('definedInteraction', handleDefinedInteraction);
-        document.addEventListener('definedInteraction', (e: Event) => {
-            const customEvent = e as CustomEvent;
-            handleDefinedInteraction(customEvent.detail.interactionType, customEvent.detail.metadata);
-        });
-        // TOO NOISY: enable if needed but tbh not worth it
-        //window.addEventListener('scroll', handleScroll, { passive: true });
 
         return () => {
-            document.removeEventListener('click', handleClick);
+            document.removeEventListener('definedInteraction', handleDefinedInteraction);
-            document.removeEventListener('definedInteraction', (e: Event) => {
-                const customEvent = e as CustomEvent;
-                handleDefinedInteraction(customEvent.detail.interactionType, customEvent.detail.metadata);
-            });
-            //window.removeEventListener('scroll', handleScroll);
         };
-    }, []);
+    }, [ready]);
 };

web/src/hooks/useSession.ts

@@ -0,0 +1,38 @@
+import { useEffect, useState } from 'react';
+
+type SessionState = {
+  sessionId: string | null;
+  experimentId: string | null;
+  isLoading: boolean;
+};
+
+export const useSession = () => {
+  const [state, setState] = useState<SessionState>({
+    sessionId: null,
+    experimentId: null,
+    isLoading: true,
+  });
+
+  useEffect(() => {
+    const fetchSession = async () => {
+      try {
+        const res = await fetch('/api/session');
+        if (!res.ok) throw new Error(`fetch failed: ${res.status}`);
+
+        const data = await res.json();
+        setState({
+          sessionId: data.sessionId || null,
+          experimentId: data.experimentId || null,
+          isLoading: false,
+        });
+      } catch (err) {
+        console.error('session fetch error:', err);
+        setState({ sessionId: null, experimentId: null, isLoading: false });
+      }
+    };
+
+    fetchSession();
+  }, []);
+
+  return state;
+};

web/src/lib/config.ts

@@ -0,0 +1,30 @@
+import { z } from 'zod';
+
+type Env = z.infer<typeof envSchema>;
+const envSchema = z.object({
+    STORE_MODE: z.enum(['hotel', 'airline'], {
+        message: 'STORE_MODE must be either "hotel" or "airline"'
+    }),
+    NEXT_PUBLIC_API_BASE: z.string().url({
+        message: 'NEXT_PUBLIC_API_BASE must be a valid URL (e.g., http://localhost:3000)'
+    }),
+    NEXT_PUBLIC_APP_ENV: z.enum(['dev', 'prod'], {
+        message: 'NEXT_PUBLIC_APP_ENV must be either "dev" or "prod"'
+    }),
+});
+
+// parse and validate env at module load, fail fast with descriptive errors
+const parseEnv = (): Env => {
+    const result = envSchema.safeParse({
+        STORE_MODE: process.env.STORE_MODE,
+        NEXT_PUBLIC_API_BASE: process.env.NEXT_PUBLIC_API_BASE,
+        NEXT_PUBLIC_APP_ENV: process.env.NEXT_PUBLIC_APP_ENV,
+    });
+    if (!result.success) {
+        const errors = result.error.issues.map((err) => `${err.path.join('.')}: ${err.message}`).join('\n');
+        throw new Error(`Environment validation failed:\n${errors}`);
+    }
+    return result.data;
+};
+
+export const config: Env = parseEnv();

web/src/lib/events.ts

@@ -0,0 +1,91 @@
+import { z } from 'zod';
+
+// canonical events for tracking user interactions
+export type EventName =
+  // navigation & discovery
+  | 'page_view'
+  | 'view_item_page'
+  | 'learn_more_about_item'
+  // cart operations
+  | 'add_item_to_cart'
+  | 'remove_item'
+  | 'checkout_start'
+  | 'purchase_complete'
+  // filtering & search
+  | 'search'
+  | 'filter_for_date'
+  | 'filter_for_amenities'
+  | 'filter_for_price'
+  | 'sort_change'
+  // dwell signals (Ns threshold)
+  | 'hover_over_title'
+  | 'hover_over_paragraph'
+  | 'hover_over_link'
+  | 'hover_over_button'
+  // session
+  | 'session_start';
+
+export const eventNames: readonly EventName[] = [
+  'page_view',
+  'view_item_page',
+  'learn_more_about_item',
+  'add_item_to_cart',
+  'remove_item',
+  'checkout_start',
+  'purchase_complete',
+  'search',
+  'filter_for_date',
+  'filter_for_amenities',
+  'filter_for_price',
+  'sort_change',
+  'hover_over_title',
+  'hover_over_paragraph',
+  'hover_over_link',
+  'hover_over_button',
+  'session_start',
+] as const;
+
+export interface EventBase {
+  sessionId: string;
+  experimentId?: string;
+  storeMode: 'hotel' | 'airline';
+  ts: string; // ISO8601
+  page: string;
+  eventName: EventName;
+  productId?: string;
+  metadata?: Record<string, unknown>;
+  userAgent?: string;
+}
+
+// zod schema for runtime validation
+export const eventBaseSchema = z.object({
+  sessionId: z.string().min(1),
+  experimentId: z.string().optional(),
+  storeMode: z.enum(['hotel', 'airline']),
+  ts: z.string().datetime(), // validates ISO8601
+  page: z.string().min(1),
+  eventName: z.enum([
+    'page_view',
+    'view_item_page',
+    'learn_more_about_item',
+    'add_item_to_cart',
+    'remove_item',
+    'checkout_start',
+    'purchase_complete',
+    'search',
+    'filter_for_date',
+    'filter_for_amenities',
+    'filter_for_price',
+    'sort_change',
+    'hover_over_title',
+    'hover_over_paragraph',
+    'hover_over_link',
+    'hover_over_button',
+    'session_start',
+  ]),
+  productId: z.string().optional(),
+  metadata: z.record(z.string(), z.unknown()).optional(),
+  userAgent: z.string().optional(),
+});
+
+export type EventBaseValidated = z.infer<typeof eventBaseSchema>;

web/src/lib/kafka.ts

@@ -1,42 +0,0 @@
-import { Kafka, Producer } from 'kafkajs';
-
-let producer: Producer | null = null;
-
-const kafka = new Kafka({
-    clientId: 'phantom-web',
-    brokers: [`${process.env.KAFKA_HOST || 'localhost'}:${process.env.KAFKA_PORT || '9092'}`],
-});
-
-export const getProducer = async (): Promise<Producer> => {
-    if (!producer) {
-        producer = kafka.producer();
-        await producer.connect();
-    }
-    return producer;
-};
-
-export const sendInteractionEvent = async (ev: {
-    sessionId: string;
-    eventType: string;
-    targetEl?: string;
-    targetUrl?: string;
-    metadata?: Record<string, any>;
-    ts: number;
-}) => {
-    const p = await getProducer();
-    // add to the metadata
-    await p.send({
-        topic: 'user-interactions',
-        messages: [{
-            key: ev.sessionId,
-            value: JSON.stringify(ev),
-        }],
-    });
-};
-
-export const disconnect = async () => {
-    if (producer) {
-        await producer.disconnect();
-        producer = null;
-    }
-};

web/src/lib/sessionStore.ts

@@ -0,0 +1,102 @@
+type SessionData = {
+  experimentId?: string;
+  startedAt: number;
+  status: 'active' | 'stopped';
+};
+
+type ExperimentData = {
+  id: string;
+  status: 'active' | 'stopped';
+  sessionIds: string[];
+  createdAt: number;
+};
+
+const store = new Map<string, SessionData>();
+const experiments = new Map<string, ExperimentData>();
+
+const cfg = {
+  key: process.env.AIRTABLE_API_KEY,
+  base: process.env.AIRTABLE_BASE_ID,
+  table: process.env.AIRTABLE_TABLE_NAME || 'Sessions',
+};
+
+// sync session to airtable if credentials present
+const syncToAirtable = async (sid: string, data: SessionData) => {
+  if (!cfg.key || !cfg.base) return; // skip if not configured
+
+  try {
+    const url = `https://api.airtable.com/v0/${cfg.base}/${encodeURIComponent(cfg.table)}`;
+    await fetch(url, {
+      method: 'POST',
+      headers: {
+        Authorization: `Bearer ${cfg.key}`,
+        'Content-Type': 'application/json',
+      },
+      body: JSON.stringify({
+        fields: {
+          sessionId: sid,
+          experimentId: data.experimentId || '',
+          startedAt: new Date(data.startedAt).toISOString(),
+          status: data.status,
+        },
+      }),
+    });
+  } catch (err) {
+    console.error('airtable sync failed:', err);
+  }
+};
+
+export const getSession = (sid: string) => store.get(sid);
+
+export const createSession = (sid: string) => {
+  const data: SessionData = { startedAt: Date.now(), status: 'active' };
+  store.set(sid, data);
+  syncToAirtable(sid, data); // async fire-and-forget
+  return data;
+};
+
+export const setExperiment = (sid: string, expId: string) => {
+  const data = store.get(sid) || createSession(sid);
+  data.experimentId = expId;
+  store.set(sid, data);
+  syncToAirtable(sid, data);
+  return data;
+};
+
+export const stopExperiment = (sid: string) => {
+  const data = store.get(sid);
+  if (data) {
+    data.status = 'stopped';
+    store.set(sid, data);
+    syncToAirtable(sid, data);
+  }
+  return data;
+};
+
+// experiment-level operations
+export const createExperiment = (sid: string, expId: string) => {
+  const exp: ExperimentData = {
+    id: expId,
+    status: 'active',
+    sessionIds: [sid],
+    createdAt: Date.now(),
+  };
+  experiments.set(expId, exp);
+  setExperiment(sid, expId); // link session to experiment
+  console.log(`experiment ${expId} started with session ${sid}`);
+  return exp;
+};
+
+export const stopExperimentById = (expId: string) => {
+  const exp = experiments.get(expId);
+  if (exp) {
+    exp.status = 'stopped';
+    experiments.set(expId, exp);
+    console.log(`experiment ${expId} stopped`);
+  }
+  return exp;
+};
+
+export const getExperiment = (expId: string) => experiments.get(expId);
+
+export const getAllExperiments = () => Array.from(experiments.values());

web/src/proxy.ts

@@ -0,0 +1,36 @@
+import { NextRequest, NextResponse } from 'next/server';
+
+export function proxy(req: NextRequest) {
+    const mode = process.env.STORE_MODE;
+    const { pathname } = req.nextUrl;
+
+    // skip rewrites for api routes, admin routes, static files, and next internals
+    if (
+        pathname.startsWith('/api') ||
+        pathname.startsWith('/admin') ||
+        pathname.startsWith('/_next') ||
+        pathname.startsWith('/static') ||
+        pathname.includes('.')
+        // TODO: add robots.txt and sitemap.xml if needed here
+    ) {
+        return NextResponse.next();
+    }
+
+    // already prefixed with mode
+    if (pathname.startsWith(`/${mode}`)) {
+        return NextResponse.next();
+    }
+
+    // rewrite root and unprefixed paths to mode-specific route group
+    const url = req.nextUrl.clone();
+    url.pathname = `/${mode}${pathname === '/' ? '' : pathname}`;
+
+    return NextResponse.rewrite(url);
+}
+
+export const config = {
+    matcher: [
+        // match all paths except those starting with _next/static, _next/image, favicon.ico
+        '/((?!_next/static|_next/image|favicon.ico).*)',
+    ],
+};

web/src/styles/airline.css

@@ -0,0 +1,321 @@
+/* Airline Platform - Sky Blue Theme */
+
+@layer base {
+[data-mode="airline"] {
+  --accent-primary: #007aff;
+  --accent-secondary: #4caf50;
+  --accent-warning: #ff3b30;
+  --accent-primary-hover: #0051d5;
+  --accent-primary-light: #e6f2ff;
+  --text-accent: #007aff;
+  --hero-bg: linear-gradient(to bottom, white, #e6f2ff);
+}
+}
+
+@layer components {
+[data-mode="airline"] {
+  --primary-color: var(--accent-primary);
+}
+
+[data-mode="airline"] .btn-primary {
+  background-color: var(--accent-primary) !important;
+  color: #ffffff !important;
+  padding: 12px 24px;
+  font-weight: 600;
+  font-size: 1rem;
+  border-radius: var(--border-radius);
+  border: none;
+  cursor: pointer;
+  transition: all 0.2s ease;
+}
+
+[data-mode="airline"] .btn-primary:hover {
+  background-color: var(--accent-primary-hover);
+  transform: translateY(-1px);
+  box-shadow: 0 4px 12px rgba(0, 122, 255, 0.3);
+}
+
+[data-mode="airline"] .btn-secondary {
+  background-color: transparent;
+  color: var(--accent-primary);
+  border: 2px solid var(--accent-primary);
+}
+
+[data-mode="airline"] .btn-secondary:hover {
+  background-color: var(--accent-primary-light);
+}
+
+[data-mode="airline"] .badge-value {
+  background-color: var(--accent-secondary);
+  color: #ffffff;
+  padding: 4px 8px;
+  border-radius: 4px;
+  font-size: 0.875rem;
+  font-weight: 600;
+}
+
+[data-mode="airline"] .badge-warning {
+  background-color: var(--accent-warning);
+  color: #ffffff;
+  padding: 4px 8px;
+  border-radius: 4px;
+  font-size: 0.875rem;
+  font-weight: 600;
+}
+
+[data-mode="airline"] .search-form {
+  background: var(--bg-primary);
+  padding: var(--spacing-lg);
+  border-radius: var(--border-radius);
+  box-shadow: var(--shadow-card);
+}
+
+[data-mode="airline"] .flight-card {
+  display: grid;
+  grid-template-columns: 2fr 3fr 2fr;
+  gap: var(--spacing-md);
+  padding: var(--spacing-md);
+  background: var(--bg-primary);
+  border-radius: var(--border-radius);
+  box-shadow: var(--shadow-card);
+  margin-bottom: var(--spacing-md);
+  transition: box-shadow 0.2s ease;
+}
+
+[data-mode="airline"] .flight-card:hover {
+  box-shadow: 0 4px 16px rgba(0, 122, 255, 0.15);
+}
+
+[data-mode="airline"] .flight-timing {
+  display: flex;
+  flex-direction: column;
+  justify-content: center;
+}
+
+[data-mode="airline"] .flight-time {
+  font-size: 1.5rem;
+  font-weight: 700;
+  color: var(--text-primary);
+}
+
+[data-mode="airline"] .flight-airport {
+  font-size: 0.875rem;
+  color: var(--text-secondary);
+  font-weight: 500;
+}
+
+[data-mode="airline"] .flight-route {
+  display: flex;
+  flex-direction: column;
+  justify-content: center;
+  align-items: center;
+  text-align: center;
+}
+
+[data-mode="airline"] .flight-duration {
+  font-size: 0.875rem;
+  color: var(--text-secondary);
+  margin-bottom: 4px;
+}
+
+[data-mode="airline"] .flight-stops {
+  font-size: 0.875rem;
+  color: var(--text-secondary);
+  font-weight: 600;
+}
+
+[data-mode="airline"] .flight-pricing {
+  display: flex;
+  flex-direction: column;
+  justify-content: center;
+  gap: var(--spacing-sm);
+}
+
+[data-mode="airline"] .fare-option {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding: var(--spacing-sm);
+  border: 1px solid #e0e0e0;
+  border-radius: 6px;
+  transition: all 0.2s ease;
+}
+
+[data-mode="airline"] .fare-option:hover {
+  border-color: var(--accent-primary);
+  background-color: var(--accent-primary-light);
+}
+
+[data-mode="airline"] .fare-class {
+  font-size: 0.875rem;
+  font-weight: 600;
+  color: var(--text-primary);
+}
+
+[data-mode="airline"] .fare-price {
+  font-size: 1.125rem;
+  font-weight: 700;
+  color: var(--accent-primary);
+}
+
+[data-mode="airline"] .date-price-bar {
+  display: flex;
+  overflow-x: auto;
+  gap: var(--spacing-sm);
+  padding: var(--spacing-md) 0;
+  margin-bottom: var(--spacing-lg);
+}
+
+[data-mode="airline"] .date-option {
+  min-width: 100px;
+  padding: var(--spacing-sm);
+  text-align: center;
+  border: 2px solid #e0e0e0;
+  border-radius: 6px;
+  cursor: pointer;
+  transition: all 0.2s ease;
+}
+
+[data-mode="airline"] .date-option:hover {
+  border-color: var(--accent-primary);
+}
+
+[data-mode="airline"] .date-option.active {
+  border-color: var(--accent-primary);
+  background-color: var(--accent-primary-light);
+}
+
+[data-mode="airline"] .date-label {
+  font-size: 0.75rem;
+  color: var(--text-secondary);
+  margin-bottom: 4px;
+}
+
+[data-mode="airline"] .date-price {
+  font-size: 1rem;
+  font-weight: 700;
+  color: var(--accent-primary);
+}
+
+[data-mode="airline"] .progress-wizard {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  max-width: 800px;
+  margin: var(--spacing-lg) auto;
+  padding: 0 var(--spacing-md);
+}
+
+[data-mode="airline"] .wizard-step {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  flex: 1;
+  position: relative;
+}
+
+[data-mode="airline"] .wizard-step::after {
+  content: '';
+  position: absolute;
+  top: 20px;
+  left: 50%;
+  width: 100%;
+  height: 2px;
+  background: #e0e0e0;
+  z-index: -1;
+}
+
+[data-mode="airline"] .wizard-step:last-child::after {
+  display: none;
+}
+
+[data-mode="airline"] .wizard-number {
+  width: 40px;
+  height: 40px;
+  border-radius: 50%;
+  background: #e0e0e0;
+  color: var(--text-secondary);
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  font-weight: 700;
+  margin-bottom: var(--spacing-sm);
+}
+
+[data-mode="airline"] .wizard-step.active .wizard-number {
+  background: var(--accent-primary);
+  color: #ffffff;
+}
+
+[data-mode="airline"] .wizard-step.completed .wizard-number {
+  background: var(--accent-secondary);
+  color: #ffffff;
+}
+
+[data-mode="airline"] .wizard-label {
+  font-size: 0.875rem;
+  color: var(--text-secondary);
+  text-align: center;
+}
+
+[data-mode="airline"] .wizard-step.active .wizard-label {
+  color: var(--accent-primary);
+  font-weight: 600;
+}
+
+[data-mode="airline"] a {
+  color: var(--accent-primary);
+  text-decoration: none;
+}
+
+[data-mode="airline"] a:hover {
+  text-decoration: underline;
+}
+
+[data-mode="airline"] .input-field {
+  border: 2px solid #e0e0e0;
+  border-radius: 6px;
+  padding: 12px;
+  transition: border-color 0.2s ease;
+  width: 100%;
+}
+
+[data-mode="airline"] .input-field:focus {
+  border-color: var(--accent-primary);
+  box-shadow: 0 0 0 3px var(--accent-primary-light);
+}
+
+[data-mode="airline"] .filter-sidebar {
+  background: var(--bg-primary);
+  padding: var(--spacing-md);
+  border-radius: var(--border-radius);
+  box-shadow: var(--shadow-card);
+}
+
+[data-mode="airline"] .filter-section {
+  margin-bottom: var(--spacing-lg);
+}
+
+[data-mode="airline"] .filter-title {
+  font-size: 1rem;
+  font-weight: 700;
+  color: var(--text-primary);
+  margin-bottom: var(--spacing-sm);
+}
+
+[data-mode="airline"] .checkbox-label {
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-sm);
+  padding: var(--spacing-sm) 0;
+  cursor: pointer;
+}
+
+[data-mode="airline"] .checkbox-label:hover {
+  color: var(--accent-primary);
+}
+
+[data-mode="airline"] .hero-section {
+  background: var(--hero-bg);
+}
+}

web/src/styles/hotel.css

@@ -0,0 +1,418 @@
+/* Hotel Platform - Action Blue Theme */
+
+@layer base {
+[data-mode="hotel"] {
+  --accent-primary: #007aff;
+  --accent-secondary: #4caf50;
+  --accent-warning: #d9534f;
+  --accent-primary-hover: #0051d5;
+  --accent-primary-light: #e6f2ff;
+  --text-accent: #007aff;
+  --bg-tertiary: #f5f5f7;
+  --hero-bg: linear-gradient(to bottom, white, #f5f5f5);
+}
+}
+
+@layer components {
+[data-mode="hotel"] {
+  --primary-color: var(--accent-primary);
+}
+
+[data-mode="hotel"] .btn-primary {
+  background-color: var(--accent-primary);
+  color: #ffffff;
+  padding: 12px 24px;
+  font-weight: 600;
+  font-size: 1rem;
+  border-radius: var(--border-radius);
+  border: none;
+  cursor: pointer;
+  transition: all 0.2s ease;
+}
+
+[data-mode="hotel"] .btn-primary:hover {
+  background-color: var(--accent-primary-hover);
+  transform: translateY(-1px);
+  box-shadow: 0 4px 12px rgba(0, 122, 255, 0.3);
+}
+
+[data-mode="hotel"] .btn-secondary {
+  background-color: transparent;
+  color: var(--accent-primary);
+  border: 2px solid var(--accent-primary);
+}
+
+[data-mode="hotel"] .btn-secondary:hover {
+  background-color: var(--accent-primary-light);
+}
+
+[data-mode="hotel"] .badge-value {
+  background-color: var(--accent-secondary);
+  color: #ffffff;
+  padding: 4px 10px;
+  border-radius: 4px;
+  font-size: 0.875rem;
+  font-weight: 600;
+}
+
+[data-mode="hotel"] .badge-warning {
+  background-color: var(--accent-warning);
+  color: #ffffff;
+  padding: 4px 10px;
+  border-radius: 4px;
+  font-size: 0.875rem;
+  font-weight: 600;
+}
+
+[data-mode="hotel"] .badge-rating {
+  background-color: var(--accent-primary);
+  color: #ffffff;
+  padding: 6px 10px;
+  border-radius: 4px;
+  font-size: 0.875rem;
+  font-weight: 700;
+}
+
+[data-mode="hotel"] .search-form {
+  background: var(--bg-primary);
+  padding: var(--spacing-lg);
+  border-radius: var(--border-radius);
+  box-shadow: var(--shadow-card);
+  max-width: 900px;
+  margin: 0 auto;
+}
+
+[data-mode="hotel"] .hotel-card {
+  display: grid;
+  grid-template-columns: 300px 1fr auto;
+  gap: var(--spacing-md);
+  background: var(--bg-primary);
+  border-radius: var(--border-radius);
+  box-shadow: var(--shadow-card);
+  margin-bottom: var(--spacing-md);
+  overflow: hidden;
+  transition: box-shadow 0.2s ease;
+}
+
+[data-mode="hotel"] .hotel-card:hover {
+  box-shadow: 0 4px 16px rgba(0, 122, 255, 0.15);
+}
+
+[data-mode="hotel"] .hotel-image {
+  position: relative;
+  width: 100%;
+  height: 100%;
+  min-height: 220px;
+  overflow: hidden;
+}
+
+[data-mode="hotel"] .hotel-image img {
+  width: 100%;
+  height: 100%;
+  object-fit: cover;
+}
+
+[data-mode="hotel"] .image-carousel {
+  position: relative;
+}
+
+[data-mode="hotel"] .carousel-nav {
+  position: absolute;
+  bottom: var(--spacing-sm);
+  left: 50%;
+  transform: translateX(-50%);
+  display: flex;
+  gap: 6px;
+}
+
+[data-mode="hotel"] .carousel-dot {
+  width: 8px;
+  height: 8px;
+  border-radius: 50%;
+  background: rgba(255, 255, 255, 0.5);
+  cursor: pointer;
+}
+
+[data-mode="hotel"] .carousel-dot.active {
+  background: #ffffff;
+}
+
+[data-mode="hotel"] .hotel-info {
+  padding: var(--spacing-md);
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-sm);
+}
+
+[data-mode="hotel"] .hotel-name {
+  font-size: 1.25rem;
+  font-weight: 700;
+  color: var(--text-primary);
+  margin: 0;
+}
+
+[data-mode="hotel"] .hotel-location {
+  font-size: 0.875rem;
+  color: var(--text-secondary);
+  display: flex;
+  align-items: center;
+  gap: 4px;
+}
+
+[data-mode="hotel"] .hotel-rating {
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-sm);
+}
+
+[data-mode="hotel"] .rating-text {
+  font-size: 0.875rem;
+  font-weight: 600;
+  color: var(--text-primary);
+}
+
+[data-mode="hotel"] .hotel-features {
+  display: flex;
+  flex-wrap: wrap;
+  gap: var(--spacing-sm);
+  margin-top: var(--spacing-sm);
+}
+
+[data-mode="hotel"] .feature-tag {
+  padding: 4px 8px;
+  background: var(--bg-tertiary);
+  color: var(--text-secondary);
+  font-size: 0.75rem;
+  border-radius: 4px;
+}
+
+[data-mode="hotel"] .hotel-pricing {
+  padding: var(--spacing-md);
+  display: flex;
+  flex-direction: column;
+  justify-content: space-between;
+  align-items: flex-end;
+  min-width: 200px;
+}
+
+[data-mode="hotel"] .price-wrapper {
+  text-align: right;
+}
+
+[data-mode="hotel"] .price-label {
+  font-size: 0.75rem;
+  color: var(--text-secondary);
+  margin-bottom: 4px;
+}
+
+[data-mode="hotel"] .price-amount {
+  font-size: 1.75rem;
+  font-weight: 700;
+  color: var(--accent-primary);
+}
+
+[data-mode="hotel"] .price-unit {
+  font-size: 0.875rem;
+  color: var(--text-secondary);
+}
+
+[data-mode="hotel"] .price-original {
+  text-decoration: line-through;
+  color: var(--text-secondary);
+  font-size: 1rem;
+  margin-right: var(--spacing-sm);
+}
+
+[data-mode="hotel"] .urgency-message {
+  font-size: 0.75rem;
+  color: var(--accent-warning);
+  font-weight: 600;
+  margin-top: 4px;
+}
+
+[data-mode="hotel"] .free-cancellation {
+  font-size: 0.75rem;
+  color: var(--accent-secondary);
+  font-weight: 600;
+  margin-top: 4px;
+}
+
+[data-mode="hotel"] .filter-sidebar {
+  background: var(--bg-primary);
+  padding: var(--spacing-md);
+  border-radius: var(--border-radius);
+  box-shadow: var(--shadow-card);
+}
+
+[data-mode="hotel"] .filter-section {
+  margin-bottom: var(--spacing-lg);
+  padding-bottom: var(--spacing-md);
+  border-bottom: 1px solid #e0e0e0;
+}
+
+[data-mode="hotel"] .filter-section:last-child {
+  border-bottom: none;
+}
+
+[data-mode="hotel"] .filter-title {
+  font-size: 1rem;
+  font-weight: 700;
+  color: var(--text-primary);
+  margin-bottom: var(--spacing-md);
+}
+
+[data-mode="hotel"] .checkbox-label {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  padding: var(--spacing-sm) 0;
+  cursor: pointer;
+}
+
+[data-mode="hotel"] .checkbox-label:hover {
+  color: var(--accent-primary);
+}
+
+[data-mode="hotel"] .checkbox-count {
+  font-size: 0.875rem;
+  color: var(--text-secondary);
+}
+
+[data-mode="hotel"] .price-slider {
+  margin-top: var(--spacing-md);
+}
+
+[data-mode="hotel"] .slider-track {
+  width: 100%;
+  height: 6px;
+  background: #e0e0e0;
+  border-radius: 3px;
+  position: relative;
+}
+
+[data-mode="hotel"] .slider-range {
+  height: 100%;
+  background: var(--accent-primary);
+  border-radius: 3px;
+}
+
+[data-mode="hotel"] .slider-values {
+  display: flex;
+  justify-content: space-between;
+  margin-top: var(--spacing-sm);
+  font-size: 0.875rem;
+  color: var(--text-secondary);
+}
+
+[data-mode="hotel"] .map-toggle {
+  background: var(--bg-primary);
+  border: 2px solid var(--accent-primary);
+  color: var(--accent-primary);
+  padding: 12px 24px;
+  border-radius: var(--border-radius);
+  font-weight: 600;
+  cursor: pointer;
+  transition: all 0.2s ease;
+}
+
+[data-mode="hotel"] .map-toggle:hover {
+  background: var(--accent-primary);
+  color: #ffffff;
+}
+
+[data-mode="hotel"] .results-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  margin-bottom: var(--spacing-lg);
+  padding: var(--spacing-md);
+  background: var(--bg-primary);
+  border-radius: var(--border-radius);
+}
+
+[data-mode="hotel"] .sort-dropdown {
+  padding: 8px 12px;
+  border: 2px solid #e0e0e0;
+  border-radius: 6px;
+  background: var(--bg-primary);
+  cursor: pointer;
+  font-size: 0.875rem;
+}
+
+[data-mode="hotel"] .sort-dropdown:focus {
+  border-color: var(--accent-primary);
+}
+
+[data-mode="hotel"] .view-toggle {
+  display: flex;
+  gap: var(--spacing-sm);
+}
+
+[data-mode="hotel"] .view-button {
+  padding: 8px 12px;
+  background: transparent;
+  border: 2px solid #e0e0e0;
+  border-radius: 6px;
+  cursor: pointer;
+  transition: all 0.2s ease;
+}
+
+[data-mode="hotel"] .view-button.active {
+  background: var(--accent-primary);
+  color: #ffffff;
+  border-color: var(--accent-primary);
+}
+
+[data-mode="hotel"] a {
+  color: var(--accent-primary);
+  text-decoration: none;
+}
+
+[data-mode="hotel"] a:hover {
+  text-decoration: underline;
+}
+
+[data-mode="hotel"] .input-field {
+  border: 2px solid #e0e0e0;
+  border-radius: 6px;
+  padding: 12px;
+  width: 100%;
+  transition: border-color 0.2s ease;
+}
+
+[data-mode="hotel"] .input-field:focus {
+  border-color: var(--accent-primary);
+  box-shadow: 0 0 0 3px var(--accent-primary-light);
+}
+
+[data-mode="hotel"] .tab-navigation {
+  display: flex;
+  gap: 0;
+  margin-bottom: var(--spacing-lg);
+  border-bottom: 2px solid #e0e0e0;
+}
+
+[data-mode="hotel"] .tab-item {
+  padding: 12px 24px;
+  background: transparent;
+  border: none;
+  border-bottom: 3px solid transparent;
+  color: var(--text-secondary);
+  font-weight: 600;
+  cursor: pointer;
+  transition: all 0.2s ease;
+}
+
+[data-mode="hotel"] .tab-item:hover {
+  color: var(--accent-primary);
+}
+
+[data-mode="hotel"] .tab-item.active {
+  color: var(--accent-primary);
+  border-bottom-color: var(--accent-primary);
+}
+
+[data-mode="hotel"] .hero-section {
+  background: var(--hero-bg);
+}
+}