:root {
    --color-primary-50: #eef2ff;
    --color-primary-100: #dce5ff;
    --color-primary-200: #b9cbff;
    --color-primary-300: #7fa0ff;
    --color-primary-400: #4a73f5;
    --color-primary-500: #2b52d4;
    --color-primary-600: #1a365d;
    --color-primary-700: #152c4e;
    --color-primary-800: #0f1f3a;
    --color-primary-900: #0a1628;

    --color-teal-50: #f0fdfa;
    --color-teal-100: #ccfbf1;
    --color-teal-200: #99f6e4;
    --color-teal-300: #5eead4;
    --color-teal-400: #2dd4bf;
    --color-teal-500: #14b8a6;
    --color-teal-600: #0d9488;
    --color-teal-700: #0f766e;

    --color-success-500: #22c55e;
    --color-success-600: #16a34a;
    --color-warning-500: #f59e0b;
    --color-warning-600: #d97706;
    --color-error-500: #ef4444;
    --color-error-600: #dc2626;

    --color-gray-50: #f8fafc;
    --color-gray-100: #f1f5f9;
    --color-gray-200: #e2e8f0;
    --color-gray-300: #cbd5e1;
    --color-gray-400: #94a3b8;
    --color-gray-500: #64748b;
    --color-gray-600: #475569;
    --color-gray-700: #334155;
    --color-gray-800: #1e293b;
    --color-gray-900: #0f172a;

    --font-sans: 'Inter', system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
    --font-mono: ui-monospace, "Cascadia Code", "Fira Code", monospace;

    --text-xs: 0.75rem;
    --text-sm: 0.875rem;
    --text-base: 1rem;
    --text-lg: 1.125rem;
    --text-xl: 1.25rem;
    --text-2xl: 1.5rem;
    --text-3xl: 1.875rem;
    --text-4xl: 2.25rem;
    --text-5xl: 3rem;

    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-20: 5rem;
    --space-24: 6rem;

    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;

    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.07), 0 4px 6px -4px rgba(0, 0, 0, 0.04);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.07), 0 8px 10px -6px rgba(0, 0, 0, 0.03);
    --shadow-card: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
    --shadow-card-hover: 0 10px 20px rgba(0,0,0,0.08), 0 4px 8px rgba(0,0,0,0.04);

    --transition-fast: 150ms ease;
    --transition-base: 200ms ease;
    --transition-slow: 300ms ease;

    --navbar-height: 4rem;
}

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

html {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-gray-800);
    background: var(--color-gray-50);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    scroll-behavior: smooth;
}

body {
    min-height: 100dvh;
    display: flex;
    flex-direction: column;
}

main {
    flex: 1;
}

a {
    color: var(--color-primary-500);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--color-primary-600);
}

h1, h2, h3, h4, h5 {
    line-height: 1.25;
    color: var(--color-gray-900);
    letter-spacing: -0.01em;
}

h1 { font-size: var(--text-4xl); font-weight: 800; }
h2 { font-size: var(--text-3xl); font-weight: 700; }
h3 { font-size: var(--text-xl); font-weight: 600; }
h4 { font-size: var(--text-lg); font-weight: 600; }

.lead {
    font-size: var(--text-lg);
    color: var(--color-gray-500);
    line-height: 1.7;
}

img {
    max-width: 100%;
    height: auto;
}

ul, ol {
    padding-left: var(--space-6);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-6);
}

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

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

.section {
    padding: var(--space-20) 0;
}

.section--sm {
    padding: var(--space-12) 0;
}

.text-center { text-align: center; }
.text-muted { color: var(--color-gray-500); }
.text-sm { font-size: var(--text-sm); }
.text-xs { font-size: var(--text-xs); }

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0 0 0 0);
    white-space: nowrap;
    border: 0;
}

@media (max-width: 768px) {
    h1 { font-size: var(--text-3xl); }
    h2 { font-size: var(--text-2xl); }
    .section { padding: var(--space-12) 0; }
    .container { padding: 0 var(--space-4); }
}