/* CSS Variables and Reset */
:root {
    /* Base Colors */
    --color-black: #000000;
    --color-white: #ffffff;
    --color-gray-900: #1d1d1f;
    --color-gray-800: #2d2d2f;
    --color-gray-700: #424245;
    --color-gray-600: #86868b;
    --color-gray-500: #a1a1a6;
    --color-gray-400: #c9c9cd;
    --color-gray-300: #e8e8ed;
    --color-gray-200: #f5f5f7;
    --color-gray-100: #fbfbfd;
    
    --color-blue: #0071e3;
    --color-blue-dark: #0051d5;
    --color-red: #ff3b30;
    --color-red-thin: #ff453a;
    --color-green: #30d158;
    --color-purple: #bf5af2;
    
    /* Semantic Colors - Light Theme */
    --bg-primary: var(--color-white);
    --bg-secondary: var(--color-gray-100);
    --bg-tertiary: var(--color-gray-200);
    --text-primary: var(--color-gray-900);
    --text-secondary: var(--color-gray-600);
    --text-tertiary: var(--color-gray-500);
    --border-primary: var(--color-gray-300);
    --border-secondary: var(--color-gray-200);
    
    /* SVG Colors - Light Theme */
    --svg-fill-primary: var(--bg-secondary);
    --svg-fill-secondary: var(--bg-tertiary);
    --svg-stroke-primary: var(--border-primary);
    --svg-stroke-secondary: var(--color-blue);
    
    --gradient-primary: linear-gradient(135deg, #0071e3 0%, #5e5ce6 100%);
    --gradient-accent: linear-gradient(135deg, #ff375f 0%, #ff6900 100%);
    
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    
    --transition-default: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 60px rgba(0, 0, 0, 0.15);
    
    /* Code blocks */
    --code-bg: #f5f5f5;
    --code-text: #333;
    --card-border: rgba(0, 0, 0, 0.1);
    --hover-bg: rgba(0, 113, 227, 0.05);
}

/* Dark Theme */
html[data-theme="dark"] {
    /* Semantic Colors - Dark Theme */
    --bg-primary: #0d1117;
    --bg-secondary: #161b22;
    --bg-tertiary: #21262d;
    --text-primary: #f0f6fc;
    --text-secondary: #8b949e;
    --text-tertiary: #7d8590;
    --border-primary: #30363d;
    --border-secondary: #21262d;
    
    /* SVG Colors - Dark Theme */
    --svg-fill-primary: var(--bg-secondary);
    --svg-fill-secondary: var(--bg-tertiary);
    --svg-stroke-primary: var(--border-primary);
    --svg-stroke-secondary: #58a6ff;
    
    /* Dark theme shadows */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.4);
    --shadow-xl: 0 20px 60px rgba(0, 0, 0, 0.5);
    
    /* Code blocks - Dark */
    --code-bg: #1a1a1a;
    --code-text: #e8e8e8;
    --card-border: rgba(255, 255, 255, 0.1);
    --hover-bg: rgba(88, 166, 255, 0.1);
}

/* System Preference Detection */
@media (prefers-color-scheme: dark) {
    html:not([data-theme]) {
        --bg-primary: #0d1117;
        --bg-secondary: #161b22;
        --bg-tertiary: #21262d;
        --text-primary: #f0f6fc;
        --text-secondary: #8b949e;
        --text-tertiary: #7d8590;
        --border-primary: #30363d;
        --border-secondary: #21262d;
        
        --svg-fill-primary: var(--bg-secondary);
        --svg-fill-secondary: var(--bg-tertiary);
        --svg-stroke-primary: var(--border-primary);
        --svg-stroke-secondary: #58a6ff;
        
        --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
        --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.3);
        --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.4);
        --shadow-xl: 0 20px 60px rgba(0, 0, 0, 0.5);
    }
}

/* Reset */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

/* Base Styles */
html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-primary);
    font-size: 17px;
    line-height: 1.47059;
    font-weight: 400;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    overflow-x: hidden;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    letter-spacing: -0.02em;
}

h1 {
    font-size: 56px;
    line-height: 1.07143;
    font-weight: 700;
}

h2 {
    font-size: 48px;
    line-height: 1.08333;
    font-weight: 600;
}

h3 {
    font-size: 32px;
    line-height: 1.125;
    font-weight: 600;
}

h4 {
    font-size: 24px;
    line-height: 1.16667;
}

p {
    color: var(--text-secondary);
}

a {
    color: var(--color-blue);
    text-decoration: none;
    transition: var(--transition-default);
}

a:hover {
    text-decoration: underline;
}

/* Container */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}