:root {
            --bg: #ffffff;
            --bg-soft: #f7faff;
            --bg-section: #f0f5ff;
            --surface: #ffffff;
            --border: #e4eaf5;
            --border-light: #eef2fa;
            --primary: #5b6cf0;
            --primary-hover: #4a5be0;
            --primary-soft: rgba(91, 108, 240, 0.1);
            --mint: #2dd4a8;
            --mint-soft: rgba(45, 212, 168, 0.1);
            --coral: #f07068;
            --coral-soft: rgba(240, 112, 104, 0.1);
            --amber: #f0a030;
            --amber-soft: rgba(240, 160, 48, 0.1);
            --text: #1a1e2e;
            --text-secondary: #5a6178;
            --text-muted: #9aa0b4;
            --shadow-sm: 0 1px 3px rgba(26, 30, 46, 0.04), 0 1px 2px rgba(26, 30, 46, 0.02);
            --shadow-md: 0 4px 16px rgba(26, 30, 46, 0.06), 0 1px 4px rgba(26, 30, 46, 0.03);
            --shadow-lg: 0 12px 40px rgba(26, 30, 46, 0.08), 0 2px 8px rgba(26, 30, 46, 0.03);
            --radius-md: 14px;
            --radius-lg: 20px;
            --radius-xl: 28px;
            --font-display: 'Plus Jakarta Sans', sans-serif;
            --font-body: 'DM Sans', sans-serif;
        }

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

        html {
            scroll-behavior: smooth;
            font-size: 16px;
        }

        body {
            font-family: var(--font-body);
            background: var(--bg);
            color: var(--text);
            line-height: 1.7;
            overflow-x: hidden;
            min-height: 100vh;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }

        a {
            color: inherit;
            text-decoration: none;
        }
        ul {
            list-style: none;
        }

        .container {
            max-width: 1140px;
            margin: 0 auto;
            padding: 0 2rem;
        }

        header {
            position: sticky;
            top: 0;
            z-index: 100;
            background: rgba(255, 255, 255, 0.95);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--border);
        }
        header .container {
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 64px;
        }
        .logo {
            font-family: var(--font-display);
            font-size: 1.4rem;
            font-weight: 800;
            color: var(--primary);
            letter-spacing: -0.03em;
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }
        .logo-dot {
            width: 8px;
            height: 8px;
            border-radius: 50%;
            background: var(--mint);
        }
        .site-nav ul {
            display: flex;
            gap: 0.25rem;
        }
        .site-nav a {
            font-family: var(--font-display);
            font-size: 0.88rem;
            font-weight: 500;
            color: var(--text-secondary);
            padding: 0.5rem 1rem;
            border-radius: 10px;
            transition: all 0.2s ease;
        }
        .site-nav a:hover {
            color: var(--primary);
            background: var(--primary-soft);
        }
        .site-nav a[aria-current="page"] {
            color: var(--primary);
            background: var(--primary-soft);
            font-weight: 600;
        }

        main {
            position: relative;
        }

        .page-hero {
            padding: 4rem 0 3rem;
            text-align: center;
            position: relative;
            overflow: hidden;
        }
        .page-hero::before {
            content: '';
            position: absolute;
            top: -15%;
            left: 50%;
            transform: translateX(-50%);
            width: 700px;
            height: 700px;
            background:
                radial-gradient(ellipse at 40% 40%, rgba(91, 108, 240, 0.07) 0%, transparent 50%),
                radial-gradient(ellipse at 60% 55%, rgba(45, 212, 168, 0.05) 0%, transparent 45%);
            border-radius: 50%;
            pointer-events: none;
        }
        .page-hero-content {
            position: relative;
            z-index: 1;
        }
        .page-hero h1 {
            font-family: var(--font-display);
            font-size: clamp(2.5rem, 5vw, 3.8rem);
            font-weight: 800;
            letter-spacing: -0.03em;
            line-height: 1.15;
            color: var(--text);
            margin-bottom: 1rem;
        }
        .page-hero h1 .gradient-text {
            background: linear-gradient(135deg, var(--primary) 0%, var(--mint) 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .page-hero p {
            font-size: 1.1rem;
            color: var(--text-secondary);
            max-width: 560px;
            margin: 0 auto 1.5rem;
            line-height: 1.8;
        }

        .tutorial-section {
            padding: 3rem 0 5rem;
        }
        .tutorial-section:nth-child(even) {
            background: var(--bg-soft);
        }

        .section-header {
            text-align: center;
            margin-bottom: 3rem;
        }
        .section-tag {
            display: inline-flex;
            align-items: center;
            padding: 0.3rem 0.85rem;
            background: var(--primary-soft);
            border-radius: 100px;
            font-family: var(--font-display);
            font-size: 0.75rem;
            font-weight: 600;
            color: var(--primary);
            letter-spacing: 0.04em;
            margin-bottom: 1rem;
        }
        .section-header h2 {
            font-family: var(--font-display);
            font-size: clamp(2rem, 4vw, 2.8rem);
            font-weight: 800;
            letter-spacing: -0.03em;
            line-height: 1.2;
            color: var(--text);
            margin-bottom: 0.75rem;
        }
        .section-header p {
            color: var(--text-secondary);
            font-size: 1.05rem;
            max-width: 480px;
            margin: 0 auto;
        }

        .prose {
            max-width: 820px;
            margin: 0 auto;
            font-size: 0.95rem;
            color: var(--text-secondary);
            line-height: 2;
        }
        .prose h3 {
            font-family: var(--font-display);
            font-size: 1.3rem;
            font-weight: 700;
            color: var(--text);
            margin: 2.5rem 0 1rem;
            letter-spacing: -0.01em;
        }
        .prose h3:first-child { margin-top: 0; }
        .prose p { margin-bottom: 1.25rem; }
        .prose strong { color: var(--text); font-weight: 600; }
        .prose ul, .prose ol {
            padding-left: 1.5rem;
            margin-bottom: 1.25rem;
        }
        .prose li { margin-bottom: 0.5rem; }

        .code-block {
            background: var(--bg-soft);
            border: 1px solid var(--border-light);
            border-radius: var(--radius-md);
            padding: 1.25rem 1.5rem;
            margin: 1.5rem 0;
            font-family: 'DM Mono', monospace;
            font-size: 0.8rem;
            color: var(--text);
            line-height: 1.8;
            white-space: pre-wrap;
            overflow-x: auto;
            border-left: 3px solid var(--primary);
        }

        .info-card-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 1.25rem;
            margin: 2rem 0;
        }
        .info-card {
            background: var(--surface);
            border: 1px solid var(--border-light);
            border-radius: var(--radius-lg);
            padding: 1.75rem;
            transition: all 0.3s ease;
        }
        .info-card:hover {
            border-color: var(--border);
            box-shadow: var(--shadow-md);
            transform: translateY(-2px);
        }
        .info-card h4 {
            font-family: var(--font-display);
            font-size: 1rem;
            font-weight: 700;
            margin-bottom: 0.5rem;
            color: var(--text);
            letter-spacing: -0.01em;
        }
        .info-card p {
            font-size: 0.85rem;
            color: var(--text-secondary);
            line-height: 1.7;
            margin-bottom: 0.75rem;
        }
        .info-card .card-tag {
            display: inline-block;
            padding: 0.15rem 0.6rem;
            border-radius: 6px;
            font-size: 0.7rem;
            font-weight: 500;
            font-family: var(--font-display);
            letter-spacing: 0.02em;
            background: var(--primary-soft);
            color: var(--primary);
        }

        .btn {
            display: inline-flex;
            align-items: center;
            gap: 0.5rem;
            padding: 0.75rem 1.6rem;
            border-radius: 12px;
            font-family: var(--font-display);
            font-size: 0.9rem;
            font-weight: 600;
            cursor: pointer;
            border: none;
            transition: all 0.25s ease;
            letter-spacing: -0.01em;
        }
        .btn-primary {
            background: var(--primary);
            color: #fff;
            box-shadow: 0 2px 12px rgba(91, 108, 240, 0.3);
        }
        .btn-primary:hover {
            background: var(--primary-hover);
            box-shadow: 0 6px 24px rgba(91, 108, 240, 0.35);
            transform: translateY(-2px);
        }
        .btn-secondary {
            background: var(--bg);
            color: var(--text);
            border: 1px solid var(--border);
            box-shadow: var(--shadow-sm);
        }
        .btn-secondary:hover {
            border-color: var(--primary);
            color: var(--primary);
            transform: translateY(-2px);
            box-shadow: var(--shadow-md);
        }
        .btn-white {
            background: #fff;
            color: var(--primary);
            box-shadow: 0 4px 16px rgba(0,0,0,0.1);
        }
        .btn-white:hover {
            transform: translateY(-2px);
            box-shadow: 0 8px 28px rgba(0,0,0,0.15);
        }

        .cta-section {
            padding: 2rem 0 6rem;
        }
        .cta-card {
            position: relative;
            padding: 4rem 3rem;
            background: linear-gradient(135deg, var(--primary) 0%, #7b87f5 50%, var(--mint) 100%);
            border-radius: var(--radius-xl);
            text-align: center;
            overflow: hidden;
            color: #fff;
        }
        .cta-card::before {
            content: '';
            position: absolute;
            top: -40%;
            right: -20%;
            width: 400px;
            height: 400px;
            background: rgba(255,255,255,0.08);
            border-radius: 50%;
            pointer-events: none;
        }
        .cta-card h2 {
            font-family: var(--font-display);
            font-size: 2.2rem;
            font-weight: 800;
            letter-spacing: -0.03em;
            margin-bottom: 0.75rem;
            position: relative;
            z-index: 1;
        }
        .cta-card p {
            font-size: 1.05rem;
            opacity: 0.9;
            margin-bottom: 2rem;
            max-width: 460px;
            margin-left: auto;
            margin-right: auto;
            position: relative;
            z-index: 1;
        }

        footer {
            padding: 2.5rem 0;
            border-top: 1px solid var(--border-light);
        }
        footer .container {
            display: flex;
            align-items: center;
            justify-content: space-between;
        }
        .footer-left {
            display: flex;
            align-items: center;
            gap: 1.75rem;
        }
        .footer-logo {
            font-family: var(--font-display);
            font-weight: 800;
            font-size: 1.1rem;
            color: var(--primary);
        }
        .footer-copy {
            font-size: 0.78rem;
            color: var(--text-muted);
        }
        .footer-links {
            display: flex;
            gap: 1.75rem;
        }
        .footer-links a {
            font-size: 0.82rem;
            color: var(--text-muted);
            font-weight: 500;
            transition: color 0.2s ease;
        }
        .footer-links a:hover { color: var(--primary); }

        @media (max-width: 768px) {
            .logo { font-size: 1.2rem; }
            .site-nav a { font-size: 0.8rem; padding: 0.4rem 0.7rem; }
            .page-hero h1 { font-size: 2rem; }
            .cta-card { padding: 3rem 1.5rem; }
            footer .container { flex-direction: column; gap: 1.25rem; text-align: center; }
            .footer-left { flex-direction: column; gap: 0.4rem; }
        }
        @media (max-width: 480px) {
            .container { padding: 0 1.25rem; }
            header .container {
                flex-direction: column; height: auto;
                padding-top: 0.75rem; padding-bottom: 0.75rem; gap: 0.5rem;
            }
            .site-nav a { font-size: 0.78rem; padding: 0.3rem 0.55rem; }
            .info-card-grid { grid-template-columns: 1fr; }
            .cta-card h2 { font-size: 1.6rem; }
        }