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+# AGENTS.md
+
+This file provides guidelines for AI agents operating in this repository.
+
+## Project Overview
+
+A modern personal portfolio website built with **Astro 5**, **React 19**, and **Tailwind CSS 4**. Features glassmorphism design, animations via Framer Motion, and full i18n support (EN/ZH).
+
+## Build Commands
+
+```bash
+# Development server
+npm run dev
+
+# Build for production
+npm run build
+
+# Preview production build locally
+npm run preview
+```
+
+No lint or test commands are configured. Run `npm run build` to verify changes.
+
+## Code Style Guidelines
+
+### General Principles
+- Write concise, self-documenting code
+- Avoid unnecessary comments (only explain complex logic)
+- Follow existing patterns in the codebase
+- Prioritize readability over cleverness
+
+### Imports
+- Use `@/` alias for src imports (configured in tsconfig.json)
+- Order imports: React → libraries → components → utilities
+- Use named exports for components and utilities
+
+```typescript
+// Good
+import * as React from "react";
+import { Slot } from "@radix-ui/react-slot";
+import { cva, type VariantProps } from "class-variance-authority";
+import { cn } from "@/lib/utils";
+
+// Avoid
+import utils from '@/lib/utils';
+import { useState, useEffect } from 'react';
+```
+
+### TypeScript
+- Use TypeScript for all new files (.ts, .tsx)
+- Extend Astro's strict TypeScript config
+- Use explicit types for component props
+- Avoid `any`, use `unknown` or specific types
+
+```typescript
+// Good
+interface ButtonProps extends React.ButtonHTMLAttributes<HTMLButtonElement>,
+  VariantProps<typeof buttonVariants> {
+  asChild?: boolean;
+}
+
+// Avoid
+interface ButtonProps { ... } // too verbose
+const handleClick = (e: any) => { ... } // no type
+```
+
+### Components
+
+**Astro Components (.astro)**:
+- Use frontmatter fence `---` at top
+- Separate imports, props, and logic
+- Use `client:only="react"` for React components that need browser APIs
+- Use `client:load` for interactive components
+- Static content should not have client directives
+
+**React Components (.tsx)**:
+- Use `React.forwardRef` for components that need refs
+- Use class-variance-authority (CVA) for component variants
+- Use Radix UI primitives when available
+- Export components as named exports
+
+### Styling (Tailwind CSS)
+- Use Tailwind utility classes exclusively
+- Use `cn()` utility to merge classes with conditional logic
+- Avoid custom CSS; use Tailwind equivalents
+- Dark mode: prefix colors with `dark:` modifier
+
+```tsx
+// Good
+<div className={cn(
+  "base-classes",
+  variant === "primary" && "primary-classes",
+  className
+)} />
+
+// Avoid
+<div style={{ display: 'flex', padding: '16px' }}>
+```
+
+### i18n (Internationalization)
+
+- All UI text must be in `src/i18n/translations.ts`
+- Use `useTranslations(lang)` hook for text
+- Avoid hardcoded strings in .astro and .tsx files
+- Structure translations by section (nav, hero, about, etc.)
+
+```typescript
+// translations.ts
+export const translations = {
+  en: { hero: { greeting: 'Hello, I'm' } },
+  zh: { hero: { greeting: '你好，我是' } }
+}
+
+// In component
+const t = useTranslations(lang);
+<h1>{t('hero.greeting')} {name}</h1>
+```
+
+### Naming Conventions
+- **Components**: PascalCase (e.g., `Button`, `GlassHeader`)
+- **Files**: kebab-case for Astro pages, PascalCase for React components
+- **Variables/functions**: camelCase
+- **Constants**: SCREAMING_SNAKE_CASE
+- **Types/Interfaces**: PascalCase with `Props` suffix for component props
+
+### Error Handling
+- Use TypeScript types to prevent runtime errors
+- Handle null/undefined cases explicitly
+- Use optional chaining `?.` and nullish coalescing `??`
+- No try-catch unless handling specific async errors
+
+### Astro-Specific
+- Pages use file-based routing (`src/pages/**/*.astro`)
+- Dynamic routes: `[slug].astro`, `[category].astro`
+- Layouts in `src/layouts/`
+- Components in `src/components/`
+- Use Content Collections for blog posts (MDX in `src/pages/blog/posts/`)
+
+## Project Structure
+
+```
+src/
+├── components/      # UI components (React & Astro)
+│   ├── blog/        # Blog-specific components
+│   ├── layout/      # Layout components
+│   ├── markdown/    # Markdown rendering components
+│   └── ui/          # Reusable UI primitives
+├── layouts/         # Page layouts (Layout.astro, BlogLayout, etc.)
+├── pages/           # Routes (auto-routed by filename)
+│   ├── blog/        # Blog pages & posts
+│   └── zh/          # Chinese locale pages
+├── lib/             # Data & utilities
+│   └── data/        # Static data (personal-info, projects, services)
+├── styles/          # Global CSS
+├── i18n/            # Internationalization
+│   └── translations.ts
+├── types/           # TypeScript type definitions
+└── utils/           # Utility functions
+```
+
+## Important Notes
+
+- This is a bilingual site (EN/ZH); maintain both locales
+- Default language is English (`defaultLang = 'en'`)
+- Chinese pages are under `/zh/` prefix
+- Use `Astro.currentLocale` to detect current language
+- The `services` section shows skills/capabilities, not literal services
+- Include `client:only="react"` for components using browser APIs (localStorage, window, etc.)