Set up Google Analytics 4 and complete all tasks according to the technical specification.

The site where users learn English through videos: they watch videos, learn words, practice real dialogues based on these videos, and take comprehension tests. The task needs to be completed clearly according to the specifications, with a deadline of 4 days. We provide all additional information, we will contact you, and we will provide access. Here is the detailed specifications:

1. Integration
   • On the frontend, connect Google Tag Manager (GTM) or directly GA4 (gtag.js).
   • Check that events are visible in GA4 DebugView.

2. Identification
   • Before event registration, send with an anonymous user_pseudo_id (GA4 creates it automatically).
   • After registration, bind user_id and store it in all subsequent events:

gtag('config', 'G-XXXXXXX', { 'user_id': '<USER_ID>' });

3. List of events (must implement)

Onboarding
• demo_started — when the user selected "Try demo".
• demo_completed — when completed the demo lesson.
• onboarding_start — when clicked "Start for free" and proceeded to personalization.
• survey_completed — when completed the survey (level, goal, schedule).
• Parameters: level_cefr, goal, schedule.
• starter_plan_shown — shown the "learning plan" screen.
• lesson1_opened — opened the first lesson.
• lesson1_completed — completed the first lesson.
• signup_shown — shown the registration screen.
• signup_completed — registration (parameter method: email, Google, etc.).
• trial_started — activated the 7-day trial period.

Lessons
• video_watched — watched video (parameters: lesson_id, seconds).
• quiz_completed — completed the test (parameters: lesson_id, score).
• ai_dialogue_completed — completed the dialogue with AI (parameters: lesson_id, turns).

4. What we store in parameters
   • level_cefr = level (A1–C2).
   • goal = goal (work/travel/study/social/kids).
   • schedule = selected schedule (2x15, 3x15, 5x15).
   • lesson_id = lesson identifier.
   • score = test result.

5. Verification (Acceptance Criteria)
   • All events are sent to GA4 and displayed in DebugView.
   • Each event has correct parameters (for example, in survey_completed the level_cefr, goal, schedule are recorded).
   • After event registration, they are bound to user_id.
   • Server events (trial/subscription/payment) are also sent to GA4.