/**
 * Base Styles & CSS Variables
 * Foundation for all pages
 */

:root {
    /* Colors - Dark Mode First */
    --bg-primary: #0f0f0f;
    --bg-secondary: #1a1a1a;
    --bg-tertiary: #2a2a2a;
    --bg-hover: #333333;
    
    --text-primary: #ffffff;
    --text-secondary: #b3b3b3;
    --text-tertiary: #808080;
    --text-inverse: #0f0f0f;
    
    --border-color: #333333;
    --border-light: #444444;
    
    /* Accent colors */
    --primary: #667eea;
    --primary-color: #667eea; /* Alias for compatibility */
    --secondary-color: #764ba2; /* Alias for compatibility */
    --primary-dark: #5568d3;
    --primary-light: #8a9eff;
    
    --success: #22c55e;
    --warning: #eab308;
    --danger: #ef4444;
    --info: #06b6d4;
    
    /* Layout aliases for compatibility */
    --card-background: var(--bg-secondary);
    --hover-background: var(--bg-hover);
    --text-muted: var(--text-secondary);
    
    /* Spacing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-2xl: 48px;
    
    /* Typography */
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    --font-mono: 'Monaco', 'Courier New', monospace;
    
    --font-size-xs: 12px;
    --font-size-sm: 14px;
    --font-size-base: 16px;
    --font-size-lg: 18px;
    --font-size-xl: 20px;
    --font-size-2xl: 24px;
    --font-size-3xl: 32px;
    --font-size-4xl: 40px;
    
    --line-height-tight: 1.3;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.75;
    
    /* Border radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.2);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.3);
    
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* Light mode */
@media (prefers-color-scheme: light) {
    :root {
        --bg-primary: #ffffff;
        --bg-secondary: #f9f9f9;
        --bg-tertiary: #f0f0f0;
        --bg-hover: #e8e8e8;
        
        --text-primary: #0f0f0f;
        --text-secondary: #4d4d4d;
        --text-tertiary: #808080;
        --text-inverse: #ffffff;
        
        --border-color: #e0e0e0;
        --border-light: #f0f0f0;
    }
}

/* Light mode (explicit) */
html[data-theme="light"] {
    --bg-primary: #ffffff;
    --bg-secondary: #f9f9f9;
    --bg-tertiary: #f0f0f0;
    --bg-hover: #e8e8e8;
    
    --text-primary: #0f0f0f;
    --text-secondary: #4d4d4d;
    --text-tertiary: #808080;
    --text-inverse: #ffffff;
    
    --border-color: #e0e0e0;
    --border-light: #f0f0f0;
}

/* Dark mode (explicit) */
html[data-theme="dark"] {
    --bg-primary: #0f0f0f;
    --bg-secondary: #1a1a1a;
    --bg-tertiary: #2a2a2a;
    --bg-hover: #333333;
    
    --text-primary: #ffffff;
    --text-secondary: #b3b3b3;
    --text-tertiary: #808080;
    --text-inverse: #0f0f0f;
    
    --border-color: #333333;
    --border-light: #444444;
}

/* Reset & Normalize */
*,
*::before,
*::after {
    box-sizing: border-box;
}

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

body {
    margin: 0;
    padding: 0;
    font-family: var(--font-sans);
    font-size: var(--font-size-base);
    line-height: var(--line-height-normal);
    background: var(--bg-primary);
    color: var(--text-primary);
    transition: background-color var(--transition-base), color var(--transition-base);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    margin: 0;
    padding: 0;
    font-weight: 600;
    line-height: var(--line-height-tight);
}

h1 {
    font-size: var(--font-size-4xl);
}

h2 {
    font-size: var(--font-size-3xl);
}

h3 {
    font-size: var(--font-size-2xl);
}

h4 {
    font-size: var(--font-size-xl);
}

h5 {
    font-size: var(--font-size-lg);
}

h6 {
    font-size: var(--font-size-base);
}

p {
    margin: 0 0 var(--spacing-md) 0;
    padding: 0;
}

a {
    color: var(--primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--primary-light);
}

/* Lists */
ul, ol {
    margin: 0 0 var(--spacing-md) var(--spacing-lg);
    padding: 0;
}

li {
    margin-bottom: var(--spacing-sm);
}

/* Code */
code, pre {
    font-family: var(--font-mono);
    background: var(--bg-tertiary);
    border-radius: var(--radius-sm);
}

code {
    padding: 2px 6px;
    font-size: 0.9em;
}

pre {
    padding: var(--spacing-md);
    overflow-x: auto;
    margin: 0 0 var(--spacing-md) 0;
}

pre code {
    background: none;
    padding: 0;
}

/* Forms */
input, textarea, select {
    font-family: inherit;
    font-size: inherit;
    color: var(--text-primary);
}

button {
    cursor: pointer;
    font-family: inherit;
    font-size: inherit;
}

/* Images */
img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 12px;
    height: 12px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--bg-tertiary);
    border-radius: 6px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--border-color);
}

/* Selection */
::selection {
    background: var(--primary);
    color: white;
}

/* Focus */
:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

/* Utilities */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.container-sm {
    max-width: 800px;
}

.container-lg {
    max-width: 1400px;
}

/* Visibility */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* Loading state */
.loading {
    opacity: 0.6;
    pointer-events: none;
}

.spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid var(--border-color);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}