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+# GoodBrick Site
+
+Сайт производителя фасадной плитки GoodBrick с каталогом продукции.
+
+## Stack
+
+- **Frontend:** Next.js 16 + shadcn/ui + Tailwind CSS 4 (TypeScript)
+- **Backend:** .NET 9 Web API (C#)
+- **Database:** PostgreSQL 16
+- **Proxy:** Caddy 2 (auto-SSL)
+- **CI/CD:** Woodpecker CI (Gitea OAuth)
+- **Git:** Gitea (self-hosted)
+
+## Project Structure
+
+```
+GBSite/
+├── frontend/           # Next.js app
+│   ├── src/app/        # App Router pages
+│   ├── src/lib/        # Utilities
+│   ├── Dockerfile      # Multi-stage: node:20-alpine
+│   └── package.json
+├── backend/            # .NET 9 Web API
+│   ├── src/GBSite.Api/ # Main API project
+│   │   ├── Controllers/
+│   │   └── Program.cs
+│   ├── GBSite.Api.sln
+│   └── Dockerfile      # Multi-stage: dotnet sdk → aspnet runtime
+├── deploy/
+│   ├── docker-compose.prod.yml
+│   └── docker-compose.dev.yml
+├── .woodpecker/
+│   └── deploy.yml      # CI/CD pipeline
+└── CLAUDE.md           # This file
+```
+
+## Environments
+
+| Env | Frontend URL | API URL | DB |
+|-----|-------------|---------|-----|
+| **Prod** | https://new.goodbrick.com.ua | https://new.goodbrick.com.ua/api/* | prod_db |
+| **Dev** | https://dev.goodbrick.com.ua | https://dev.goodbrick.com.ua/api/* | dev_db |
+
+## Docker Containers
+
+| Container | Internal Port | Host Port | Network |
+|-----------|--------------|-----------|---------|
+| gb-prod-frontend | 3000 | 127.0.0.1:3100 | app-network |
+| gb-prod-backend | 5000 | 127.0.0.1:5100 | app-network |
+| gb-dev-frontend | 3000 | 127.0.0.1:3200 | app-network |
+| gb-dev-backend | 5000 | 127.0.0.1:5200 | app-network |
+
+## Routing (Caddy)
+
+Path-based routing — один домен для фронта и API:
+- `domain.com/*` → frontend container (port 3000)
+- `domain.com/api/*` → backend container (port 5000)
+
+Backend получает запросы с prefix `/api/` (Caddy использует `handle`, не `handle_path`).
+
+## Development
+
+### Frontend
+```bash
+cd frontend && npm install && npm run dev
+```
+
+### Backend
+```bash
+cd backend && dotnet run --project src/GBSite.Api
+```
+
+### Build locally
+```bash
+cd frontend && npm run build
+cd backend && dotnet build
+```
+
+## API Conventions
+
+- All API routes start with `/api/`
+- Controllers use attribute routing: `[Route("api/[controller]")]`
+- Health check: `GET /api/health` — returns `{ status, database, environment }`
+- Health ping: `GET /api/health/ping` — returns `{ status: "pong" }`
+
+## Frontend Conventions
+
+- App Router (not Pages Router)
+- `src/app/` — pages and API routes
+- `src/lib/` — shared utilities
+- `src/components/` — React components (create when needed)
+- shadcn/ui components via `npx shadcn@latest add <component>`
+- Server-side calls to backend use `INTERNAL_API_URL` env var
+- Client-side calls use relative paths (`/api/...`) — Caddy proxies them
+
+## Git & CI/CD
+
+- **Repo:** https://git.goodbrick.com.ua/admin/gb-site
+- **Branches:** `main` → prod deploy, `dev` → dev deploy
+- **CI:** Woodpecker auto-deploys on push (SSH to server, git pull, docker compose build & up)
+- **Commit style:** conventional, short descriptions in English
+
+## Server
+
+- **Host:** 31.131.18.254
+- **SSH:** `ssh deploy@31.131.18.254` (key-based)
+- **App location:** `/srv/apps/gb-site` (main), `/srv/apps/gb-site-dev` (dev worktree)
+- **Caddy config:** `/srv/proxy/Caddyfile`
+- **All services docs:** see SERVER.md
+
+## Database
+
+PostgreSQL доступен только внутри Docker network (container name: `postgres`).
+
+Connection string format:
+```
+Host=postgres;Port=5432;Database={db};Username={user};Password={pass}
+```
+
+Configured via env var `ConnectionStrings__Default` in docker-compose files.
+
+## Key Rules
+
+- Never commit `.env` files or secrets — credentials are in docker-compose env vars on server
+- Frontend standalone output (`output: "standalone"` in next.config.ts) — required for Docker
+- Backend listens on port 5000 (`ASPNETCORE_URLS=http://+:5000`)
+- All containers must be in `app-network` (external Docker network)
diff --git a/frontend/src/app/health/ping/route.ts b/frontend/src/app/health/ping/route.ts
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+import { NextResponse } from "next/server";
+
+export async function GET() {
+  return NextResponse.json({ status: "pong" });
+}