/* Design Tokens */
        :root {
            --bg: #FFFFFF;
            --text: #0F172A;
            --muted: #334155;
            --border: #E2E8F0;
            --accent: #2563EB;
            --accent-hover: #1d4ed8;
            --radius: 16px;
            --shadow-s: 0 1px 2px rgba(0,0,0,.04);
            --shadow-m: 0 6px 18px rgba(0,0,0,.06);
            --shadow-l: 0 16px 40px rgba(0,0,0,.08);
            --space-1: 4px;
            --space-2: 8px;
            --space-3: 12px;
            --space-4: 16px;
            --space-5: 24px;
            --space-6: 32px;
            --space-7: 48px;
            --space-8: 64px;
            --space-9: 96px;
        }

        /* Reset & Base */
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        html {
            scroll-behavior: smooth;
        }

        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'SF Pro Display', 'Inter', sans-serif;
            font-size: 16px;
            line-height: 1.6;
            color: var(--text);
            background: var(--bg);
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }

        /* Container */
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 var(--space-5);
        }

        /* Typography */
        h1 {
            font-size: clamp(2rem, 4vw, 3.5rem);
            line-height: 1.2;
            font-weight: 700;
            letter-spacing: -0.02em;
        }

        h2 {
            font-size: clamp(1.5rem, 3vw, 2.5rem);
            line-height: 1.3;
            font-weight: 600;
            letter-spacing: -0.01em;
            margin-bottom: var(--space-6);
        }

        h3 {
            font-size: clamp(1.25rem, 2vw, 1.5rem);
            line-height: 1.4;
            font-weight: 600;
        }

        .text-muted {
            color: var(--muted);
        }

        /* Navigation */
        header {
            position: sticky;
            top: 0;
            background: rgba(255, 255, 255, 0.95);
            backdrop-filter: blur(10px);
            -webkit-backdrop-filter: blur(10px);
            border-bottom: 1px solid var(--border);
            z-index: 1000;
            transition: box-shadow 200ms ease-out;
        }

        header.scrolled {
            box-shadow: var(--shadow-m);
        }

        nav {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: var(--space-4) 0;
        }

        .logo {
            font-size: 1.25rem;
            font-weight: 700;
            letter-spacing: -0.01em;
        }

        .nav-links {
            display: flex;
            gap: var(--space-6);
            list-style: none;
        }

        .nav-link {
            color: var(--text);
            text-decoration: none;
            position: relative;
            padding: var(--space-2) 0;
            transition: color 180ms ease-out;
        }

        .nav-link::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 50%;
            width: 0;
            height: 2px;
            background: var(--accent);
            transform: translateX(-50%);
            transition: width 180ms ease-out;
        }

        .nav-link:hover::after,
        .nav-link:focus-visible::after {
            width: 100%;
        }

        .nav-link:focus-visible {
            outline: 2px solid var(--accent);
            outline-offset: 4px;
            border-radius: 2px;
        }

        /* Hero Section */
        .hero {
            padding: var(--space-9) 0;
            text-align: center;
        }

        .hero h1 {
            margin-bottom: var(--space-5);
        }

        .hero .subtitle {
            font-size: clamp(1.125rem, 2vw, 1.375rem);
            color: var(--muted);
            margin-bottom: var(--space-7);
            max-width: 600px;
            margin-left: auto;
            margin-right: auto;
        }

        /* Buttons */
        .button-group {
            display: flex;
            gap: var(--space-4);
            justify-content: center;
            flex-wrap: wrap;
        }

        .btn {
            padding: var(--space-3) var(--space-6);
            border-radius: var(--radius);
            text-decoration: none;
            font-weight: 500;
            display: inline-block;
            transition: all 180ms ease-out;
            cursor: pointer;
            border: none;
            font-size: 1rem;
        }

        .btn-primary {
            background: var(--accent);
            color: white;
            box-shadow: var(--shadow-s);
        }

        .btn-primary:hover {
            transform: translateY(-1px) scale(1.01);
            box-shadow: var(--shadow-m);
            background: var(--accent-hover);
        }

        .btn-primary:active {
            transform: scale(0.99);
            box-shadow: var(--shadow-s);
        }

        .btn-primary:focus-visible {
            outline: 2px solid var(--accent);
            outline-offset: 2px;
        }

        .btn-secondary {
            background: transparent;
            color: var(--text);
            border: 2px solid var(--border);
        }

        .btn-secondary:hover {
            border-color: var(--accent);
            color: var(--accent);
            transform: translateY(-1px);
        }

        .btn-secondary:focus-visible {
            outline: 2px solid var(--accent);
            outline-offset: 2px;
        }

        /* Features Section */
        .features {
            padding: var(--space-8) 0;
            background: linear-gradient(to bottom, #FAFBFC, #FFFFFF);
        }

        .grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: var(--space-5);
            margin-top: var(--space-7);
        }

        .feature-card {
            background: var(--bg);
            padding: var(--space-6);
            border-radius: var(--radius);
            border: 1px solid var(--border);
            transition: all 200ms ease-out;
            cursor: pointer;
            position: relative;
        }

        .feature-card:hover {
            transform: translateY(-4px) scale(1.01);
            box-shadow: var(--shadow-l);
            border-color: var(--accent);
        }

        .feature-card:focus-visible {
            outline: 2px solid var(--accent);
            outline-offset: 2px;
        }

        .feature-icon {
            width: 48px;
            height: 48px;
            background: var(--accent);
            border-radius: 12px;
            margin-bottom: var(--space-4);
            display: flex;
            align-items: center;
            justify-content: center;
            transition: transform 160ms ease-out;
        }

        .feature-card:hover .feature-icon {
            transform: translateY(-2px) rotate(3deg);
        }

        .feature-icon svg {
            width: 24px;
            height: 24px;
            color: white;
        }

        .feature-card h3 {
            margin-bottom: var(--space-3);
        }

        .feature-card p {
            color: var(--muted);
            opacity: 0.9;
            transition: opacity 180ms ease-out 60ms;
        }

        .feature-card:hover p {
            opacity: 1;
        }

        /* Showcase Section */
        .showcase {
            padding: var(--space-8) 0;
        }

        .showcase-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
            gap: var(--space-6);
            margin-top: var(--space-7);
        }

        .showcase-card {
            border-radius: var(--radius);
            overflow: hidden;
            background: var(--bg);
            border: 1px solid var(--border);
            transition: all 220ms ease-out;
            cursor: pointer;
        }

        .showcase-card:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-l);
        }

        .showcase-card:focus-visible {
            outline: 2px solid var(--accent);
            outline-offset: 2px;
        }

        .showcase-image {
            aspect-ratio: 16/9;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            overflow: hidden;
            position: relative;
        }

        .showcase-image::after {
            content: '';
            position: absolute;
            inset: 0;
            background: rgba(0,0,0,0);
            transition: background 220ms ease-out;
        }

        .showcase-card:hover .showcase-image::after {
            background: rgba(255,255,255,0.1);
        }

        .showcase-content {
            padding: var(--space-5);
        }

        .showcase-content h3 {
            margin-bottom: var(--space-2);
        }

        .showcase-content p {
            color: var(--muted);
            font-size: 0.95rem;
        }

        /* CTA Section */
        .cta {
            padding: var(--space-9) 0;
            text-align: center;
            background: linear-gradient(to bottom, #FAFBFC, #FFFFFF);
        }

        .cta h2 {
            margin-bottom: var(--space-4);
        }

        .cta p {
            color: var(--muted);
            font-size: 1.125rem;
            margin-bottom: var(--space-6);
            max-width: 600px;
            margin-left: auto;
            margin-right: auto;
        }

        /* Footer */
        footer {
            padding: var(--space-7) 0;
            border-top: 1px solid var(--border);
        }

        .footer-content {
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: var(--space-5);
        }

        .social-links {
            display: flex;
            gap: var(--space-4);
        }

        .social-link {
            width: 40px;
            height: 40px;
            border-radius: 50%;
            background: var(--border);
            display: flex;
            align-items: center;
            justify-content: center;
            transition: all 180ms ease-out;
            text-decoration: none;
        }

        .social-link:hover {
            background: var(--accent);
            transform: translateY(-2px);
        }

        .social-link:focus-visible {
            outline: 2px solid var(--accent);
            outline-offset: 2px;
        }

        .social-link svg {
            width: 20px;
            height: 20px;
            color: var(--text);
            transition: color 180ms ease-out;
        }

        .social-link:hover svg {
            color: white;
        }

        /* Mobile Responsiveness */
        @media (max-width: 640px) {
            .nav-links {
                gap: var(--space-4);
                font-size: 0.9rem;
            }

            .grid,
            .showcase-grid {
                grid-template-columns: 1fr;
            }

            .button-group {
                flex-direction: column;
                align-items: center;
            }

            .btn {
                width: 100%;
                max-width: 280px;
            }

            .footer-content {
                flex-direction: column;
                text-align: center;
            }
        }

        /* Reduced Motion */
        @media (prefers-reduced-motion: reduce) {
            * {
                animation-duration: 0.01ms !important;
                animation-iteration-count: 1 !important;
                transition-duration: 0.01ms !important;
            }

            html {
                scroll-behavior: auto;
            }
        }

        /* Focus Visible Polyfill for older browsers */
        .js-focus-visible :focus:not(.focus-visible) {
            outline: none;
        }