/* ===================================
   MODERN DESIGN SYSTEM
   =================================== */

:root {
    /* Color Palette - Modern & Vibrant */
    --color-primary: #6366f1;
    --color-primary-light: #818cf8;
    --color-primary-dark: #4f46e5;
    --color-secondary: #06b6d4;
    --color-accent: #f59e0b;
    --color-success: #10b981;
    --color-danger: #ef4444;
    --color-warning: #ecc94b;
    
    /* Neutral Colors - Light Mode Defaults */
    --color-bg-primary: #ffffff;
    --color-bg-secondary: #f8fafc;
    --color-bg-tertiary: #f1f5f9;
    --color-bg-dark: #0f172a;
    --color-text-primary: #0f172a;
    --color-text-secondary: #475569;
    --color-text-tertiary: #94a3b8;
    --color-border: #e2e8f0;
    
    /* Spacing System */
    --space-xs: 0.5rem;
    --space-sm: 0.75rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    --space-3xl: 4rem;
    
    /* Typography */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    --font-size-5xl: 3rem;
    --font-size-6xl: 3.75rem;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;
    
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark Mode - System Preference */
@media (prefers-color-scheme: dark) {
    :root {
        --color-bg-primary: #0f172a;
        --color-bg-secondary: #1e293b;
        --color-bg-tertiary: #334155;
        --color-bg-dark: #020617;
        --color-text-primary: #f8fafc;
        --color-text-secondary: #cbd5e1;
        --color-text-tertiary: #64748b;
        --color-border: #334155;
    }
}

/* Light Mode Override - Manual Toggle */
body.light-mode {
    --color-bg-primary: #ffffff;
    --color-bg-secondary: #f8fafc;
    --color-bg-tertiary: #f1f5f9;
    --color-bg-dark: #0f172a;
    --color-text-primary: #0f172a;
    --color-text-secondary: #475569;
    --color-text-tertiary: #94a3b8;
    --color-border: #e2e8f0;
}

/* ===================================
   BASE STYLES & RESETS
   =================================== */

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--color-text-primary);
    background: var(--color-bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    padding: 0 var(--space-xs);
}