:root {
            --hjuo-primary: #1a73e8;
            --hjuo-accent: #34a853;
            --hjuo-dark: #202124;
            --hjuo-light: #f8f9fa;
            --hjuo-gray: #5f6368;
            --hjuo-code-bg: #1e1e1e;
            --hjuo-radius: 12px;
            --hjuo-spacing: 8px;
            --hjuo-max-width: 1400px;
        }

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

        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
            line-height: 1.7;
            color: var(--hjuo-dark);
            background-color: #ffffff;
            word-break: keep-all;
            overflow-x: hidden;
        }

        /* Typography */
        h1, h2, h3 {
            line-height: 1.2;
            margin-bottom: calc(var(--hjuo-spacing) * 3);
            white-space: normal;
            word-break: keep-all;
        }

        p {
            margin-bottom: calc(var(--hjuo-spacing) * 2);
            font-size: clamp(1rem, 0.5vw + 0.8rem, 1.2rem);
            color: var(--hjuo-gray);
            overflow-wrap: break-word;
        }

        /* Layout Helpers */
        .hjuo-container {
            max-width: var(--hjuo-max-width);
            margin: 0 auto;
            padding: 0 calc(var(--hjuo-spacing) * 4);
        }

        .hjuo-flex {
            display: flex;
            flex-wrap: wrap;
        }

        .hjuo-flex > * {
            min-width: 0;
        }

        /* Navigation */
        .hjuo-header {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            background: rgba(255, 255, 255, 0.85);
            backdrop-filter: blur(12px);
            z-index: 1000;
            border-bottom: 1px solid rgba(0,0,0,0.05);
            padding: calc(var(--hjuo-spacing) * 2) 0;
        }

        .hjuo-nav-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
        }

        .hjuo-logo img {
            height: 32px;
            width: auto;
        }

        .hjuo-nav-menu {
            display: flex;
            list-style: none;
            flex-wrap: wrap;
            gap: calc(var(--hjuo-spacing) * 3);
        }

        .hjuo-nav-item a {
            text-decoration: none;
            color: var(--hjuo-dark);
            font-weight: 500;
            font-size: 0.95rem;
            padding: var(--hjuo-spacing) calc(var(--hjuo-spacing) * 2);
            border-radius: 6px;
            transition: all 0.3s ease;
        }

        .hjuo-nav-item a:hover {
            color: var(--hjuo-primary);
            background: rgba(26, 115, 232, 0.05);
        }

        .hjuo-nav-item.active a {
            color: #ffffff;
            background: var(--hjuo-primary);
        }

        /* Hero Section - Unique Diagonal Split */
        .hjuo-hero {
            padding-top: 160px;
            padding-bottom: 96px;
            background: linear-gradient(135deg, #f1f3f4 0%, #ffffff 100%);
            position: relative;
            overflow: hidden;
        }

        .hjuo-hero::before {
            content: "";
            position: absolute;
            top: -20%;
            right: -10%;
            width: 60%;
            height: 140%;
            background: var(--hjuo-primary);
            transform: skewX(-15deg);
            z-index: 0;
            opacity: 0.03;
        }

        .hjuo-hero-content {
            position: relative;
            z-index: 1;
            flex: 1;
            min-width: 320px;
        }

        .hjuo-hero-title {
            font-size: clamp(2.5rem, 5vw + 1rem, 4.5rem);
            font-weight: 800;
            color: var(--hjuo-dark);
            letter-spacing: -1px;
        }

        .hjuo-hero-subtitle {
            max-width: 600px;
        }

        .hjuo-f12-badge {
            display: inline-block;
            background: var(--hjuo-dark);
            color: #fff;
            padding: 12px 24px;
            border-radius: 16px;
            font-family: "Courier New", Courier, monospace;
            font-size: 1.5rem;
            box-shadow: 0 10px 30px rgba(0,0,0,0.15);
            margin-bottom: 24px;
            border: 2px solid #3c4043;
        }

        /* Feature Grid */
        .hjuo-section {
            padding: 96px 0;
        }

        .hjuo-engine-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
            gap: 32px;
            margin-top: 48px;
        }

        .hjuo-feature-card {
            background: #ffffff;
            border: 1px solid #e8eaed;
            padding: 40px;
            border-radius: var(--hjuo-radius);
            transition: transform 0.3s ease, box-shadow 0.3s ease;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }

        .hjuo-feature-card:hover {
            transform: translateY(-8px);
            box-shadow: 0 20px 40px rgba(0,0,0,0.05);
            border-color: var(--hjuo-primary);
        }

        .hjuo-module-name {
            font-size: 1.5rem;
            font-weight: 700;
            color: var(--hjuo-primary);
            margin-bottom: 16px;
        }

        .hjuo-technical-logic {
            font-size: 1rem;
            color: var(--hjuo-gray);
            margin-bottom: 24px;
        }

        .hjuo-stats-pill {
            display: inline-block;
            background: rgba(52, 168, 83, 0.1);
            color: var(--hjuo-accent);
            padding: 6px 12px;
            border-radius: 20px;
            font-size: 0.85rem;
            font-weight: 600;
        }

        /* DevTools Content Area */
        .hjuo-devtools-main {
            background: var(--hjuo-code-bg);
            color: #d4d4d4;
            border-radius: 24px;
            overflow: hidden;
            box-shadow: 0 40px 100px rgba(0,0,0,0.3);
            margin-top: -64px;
            position: relative;
            z-index: 10;
        }

        .hjuo-devtools-header {
            background: #333333;
            padding: 12px 24px;
            display: flex;
            gap: 8px;
            border-bottom: 1px solid #444;
        }

        .hjuo-dot { width: 12px; height: 12px; border-radius: 50%; }
        .hjuo-dot-red { background: #ff5f56; }
        .hjuo-dot-yellow { background: #ffbd2e; }
        .hjuo-dot-green { background: #27c93f; }

        .hjuo-devtools-body {
            padding: 48px;
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 48px;
            align-items: center;
        }

        .hjuo-code-content {
            font-family: 'Fira Code', 'Consolas', monospace;
            font-size: 0.9rem;
            line-height: 1.8;
        }

        .hjuo-keyword-highlight { color: #569cd6; }
        .hjuo-string-highlight { color: #ce9178; }
        .hjuo-comment-highlight { color: #6a9955; }

        /* User Flow Steps */
        .hjuo-steps {
            display: flex;
            gap: 24px;
            margin-top: 64px;
            counter-reset: step-counter;
        }

        .hjuo-step-item {
            flex: 1;
            min-width: 260px;
            padding: 32px;
            background: #f8f9fa;
            border-radius: 16px;
            position: relative;
        }

        .hjuo-step-item::before {
            counter-increment: step-counter;
            content: counter(step-counter);
            position: absolute;
            top: -20px;
            left: 20px;
            width: 40px;
            height: 40px;
            background: var(--hjuo-primary);
            color: #fff;
            display: flex;
            align-items: center;
            justify-content: center;
            border-radius: 50%;
            font-weight: 700;
            box-shadow: 0 4px 10px rgba(26, 115, 232, 0.3);
        }

        /* Footer */
        .hjuo-footer {
            background: var(--hjuo-dark);
            color: #ffffff;
            padding: 80px 0 40px;
            margin-top: 96px;
        }

        .hjuo-footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr;
            gap: 64px;
            border-bottom: 1px solid rgba(255,255,255,0.1);
            padding-bottom: 48px;
            margin-bottom: 32px;
        }

        .hjuo-brand-text {
            font-size: 1.5rem;
            font-weight: 800;
            margin-bottom: 16px;
            background: linear-gradient(90deg, #fff, #999);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }

        .hjuo-footer-link {
            display: block;
            color: #9aa0a6;
            text-decoration: none;
            margin-bottom: 12px;
            transition: color 0.3s ease;
        }

        .hjuo-footer-link:hover {
            color: #ffffff;
        }

        .hjuo-copyright {
            color: #80868b;
            font-size: 0.85rem;
            text-align: center;
        }

        /* Responsive */
        @media (max-width: 992px) {
            .hjuo-devtools-body {
                grid-template-columns: 1fr;
            }
            .hjuo-hero-title {
                font-size: 3rem;
            }
        }

        @media (max-width: 768px) {
            .hjuo-nav-menu {
                display: none; /* In a real scenario, this would be a hamburger menu */
            }
            .hjuo-hero {
                padding-top: 120px;
                text-align: center;
            }
            .hjuo-hero-subtitle {
                margin: 0 auto 24px;
            }
            .hjuo-footer-grid {
                grid-template-columns: 1fr;
                gap: 32px;
            }
            .hjuo-steps {
                flex-direction: column;
            }
        }