Nai Snow — Wellness in every cup 🍃

Build-your-own health tea web app with an AI Tea Master, bonus points, favorites, cart, Google-style sign-in, EN/简体中文 and light/dark themes. The business case as a working website (mobile + desktop).

Features

• 🍵 Tea builder — 8 teas, milk options, sweetness levels, healthy boosters (ginger, ginseng, goji…), toppings, hot/iced. Every ingredient shows a concise health benefit and contraindication warnings (diabetes, allergies, lactose).
• 🥤 Live cup preview — the cup fills with the real tea color, pearls sink, steam/ice animate.
• 🤖 AI Tea Master (OpenAI, floating widget) — unlocks after 3 orders; learns from order history, star ratings and its own taste memory, which it updates itself ("remember: I'm lactose intolerant" → never suggests fresh milk). Free plan: 5 AI teas/month; Nai+ subscription = unlimited (first month free, then ¥28/mo).
• 🎉 20% off the first order, ⭐ 5% bonus points that expire in 14 days.
• ❤️ Favorites — save your builds or AI recipes, reorder in one tap.
• 🛒 Cart for multiple drinks, 🔐 Google-style sign-in required to order (demo account chooser, no real OAuth needed).
• 💬 Feedback on all 9 feature aspects, 🌗 dark/light theme, 🌐 EN / 中文.

Run locally

npm install
cp .env.example .env   # paste your OpenAI API key into .env
npm start              # → http://localhost:3000

Demo data lives in the browser's localStorage ("Reset demo data" is in Profile).

AI model

OPENAI_MODEL=gpt-5-mini (default). Cheaper alternative: gpt-4o-mini. The key stays on the server / serverless function — never sent to the browser.

Deploy to Vercel

1. Push this folder to a GitHub repo (or use npx vercel directly).
2. In vercel.com → Add New Project → import the repo. Framework preset: Other. No build command needed.
3. In Settings → Environment Variables add:
   • OPENAI_API_KEY = your key
   • OPENAI_MODEL = gpt-5-mini (optional)
4. Deploy. The static site is served from public/, and api/ai.js runs as a serverless function at /api/ai.

CLI alternative:

npx vercel            # first deploy, answer the prompts
npx vercel env add OPENAI_API_KEY
npx vercel --prod