:root {
            --orange: #ea7600;
            --orange-dim: rgba(234,118,0,0.15);
            --bg: #1d1d1d;
            --bg-card: #252525;
            --bg-panel: #2b2b2b;
            --border: #3a3a3a;
            --text: #e5e5e5;
            --text-muted: #888;
        }

        * { box-sizing: border-box; }

        body {
            font-family: 'Inter', sans-serif;
            background-color: var(--bg);
            color: var(--text);
            overflow-x: hidden;
        }

        /* ─── Scrollbar ─── */
        ::-webkit-scrollbar { width: 8px; }
        ::-webkit-scrollbar-track { background: #2b2b2b; }
        ::-webkit-scrollbar-thumb { background: #555; border-radius: 4px; }
        ::-webkit-scrollbar-thumb:hover { background: var(--orange); }

        /* ─── Grid background ─── */
        .grid-bg {
            background-image:
                linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
                linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
            background-size: 40px 40px;
        }

        /* ─── Reveal animation ─── */
        .reveal {
            opacity: 0;
            transform: translateY(28px);
            transition: opacity 0.7s ease-out, transform 0.7s ease-out;
        }
        .reveal.active {
            opacity: 1;
            transform: translateY(0);
        }

        /* ─── Orange accent ─── */
        .blender-orange { color: var(--orange); }
        .bg-blender-orange { background-color: var(--orange); }
        .border-blender-orange { border-color: var(--orange); }

        /* ─── Mono tag ─── */
        .mono { font-family: 'Space Mono', monospace; }

        /* ─── Hero canvas ─── */
        #hero-canvas {
            position: absolute;
            inset: 0;
            pointer-events: none;
            opacity: 0.35;
        }

        /* ─── Module card ─── */
        .module-card {
            background: var(--bg-card);
            border: 1px solid var(--border);
            border-radius: 16px;
            transition: border-color 0.3s, transform 0.3s, box-shadow 0.3s;
            cursor: pointer;
            position: relative;
            overflow: hidden;
        }
        .module-card::before {
            content: '';
            position: absolute;
            inset: 0;
            background: linear-gradient(135deg, var(--orange-dim), transparent 60%);
            opacity: 0;
            transition: opacity 0.4s;
            pointer-events: none;
        }
        .module-card:hover {
            border-color: var(--orange);
            transform: translateY(-4px);
            box-shadow: 0 12px 40px rgba(234,118,0,0.15);
        }
        .module-card:hover::before { opacity: 1; }

        /* ─── Module number ─── */
        .module-number {
            font-family: 'Space Mono', monospace;
            font-size: 11px;
            color: var(--orange);
            letter-spacing: 2px;
            text-transform: uppercase;
        }

        /* ─── Tag pill ─── */
        .tag-pill {
            display: inline-block;
            background: rgba(234,118,0,0.1);
            border: 1px solid rgba(234,118,0,0.25);
            color: var(--orange);
            font-size: 10px;
            font-weight: 700;
            letter-spacing: 1.5px;
            text-transform: uppercase;
            padding: 3px 10px;
            border-radius: 100px;
        }

        /* ─── Progress bar ─── */
        .progress-track {
            background: #333;
            border-radius: 4px;
            height: 4px;
            overflow: hidden;
        }
        .progress-fill {
            height: 100%;
            background: linear-gradient(90deg, var(--orange), #ffb347);
            border-radius: 4px;
            transition: width 1.2s cubic-bezier(0.16,1,0.3,1);
            width: 0;
        }

        /* ─── Lesson list item ─── */
        .lesson-item {
            border-left: 2px solid var(--border);
            padding-left: 16px;
            transition: border-color 0.2s;
        }
        .lesson-item:hover { border-color: var(--orange); }

        /* ─── Nav ─── */
        nav {
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            z-index: 50;
            background: rgba(29,29,29,0.85);
            backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--border);
        }
        nav.scrolled {
            border-bottom-color: rgba(234,118,0,0.3);
        }

        /* ─── Stat card ─── */
        .stat-card {
            background: var(--bg-panel);
            border: 1px solid var(--border);
            border-radius: 12px;
            padding: 20px 24px;
        }

        /* ─── Section title bar ─── */
        .section-title {
            border-left: 4px solid var(--orange);
            padding-left: 16px;
        }

        /* ─── Blender logo svg float ─── */
        @keyframes float {
            0%,100% { transform: translateY(0px) rotate(-2deg); }
            50% { transform: translateY(-12px) rotate(2deg); }
        }
        .float-logo { animation: float 6s ease-in-out infinite; }

        /* ─── Arrow bounce ─── */
        @keyframes bounce { 0%,100% { transform: translateY(0); } 50% { transform: translateY(8px); } }
        .bounce { animation: bounce 2s ease-in-out infinite; }

        /* ─── Glow dot ─── */
        .glow-dot {
            width: 8px; height: 8px;
            border-radius: 50%;
            background: var(--orange);
            box-shadow: 0 0 10px var(--orange);
            display: inline-block;
        }

        /* ─── Tooltip ─── */
        [data-tooltip] { position: relative; }
        [data-tooltip]::after {
            content: attr(data-tooltip);
            position: absolute;
            bottom: calc(100% + 8px);
            left: 50%;
            transform: translateX(-50%);
            background: #1a1a1a;
            border: 1px solid var(--border);
            color: #ddd;
            font-size: 12px;
            white-space: nowrap;
            padding: 5px 10px;
            border-radius: 6px;
            pointer-events: none;
            opacity: 0;
            transition: opacity 0.2s;
        }
        [data-tooltip]:hover::after { opacity: 1; }

        /* ─── Expandable module detail ─── */
        .module-detail {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.5s cubic-bezier(0.16,1,0.3,1);
        }
        .module-detail.open { max-height: 800px; }

        /* ─── Road connector ─── */
        .road-line {
            width: 2px;
            background: linear-gradient(to bottom, var(--orange), transparent);
            margin: 0 auto;
            flex-shrink: 0;
        }

        /* ─── CTA Button ─── */
        .cta-btn {
            background: var(--orange);
            color: #fff;
            font-weight: 700;
            border-radius: 10px;
            padding: 14px 32px;
            border: none;
            cursor: pointer;
            font-size: 15px;
            transition: background 0.2s, transform 0.2s, box-shadow 0.2s;
            letter-spacing: 0.3px;
        }
        .cta-btn:hover {
            background: #ff8a1a;
            transform: translateY(-2px);
            box-shadow: 0 8px 24px rgba(234,118,0,0.35);
        }

        .cta-btn-ghost {
            background: transparent;
            color: var(--orange);
            font-weight: 600;
            border-radius: 10px;
            padding: 13px 32px;
            border: 1.5px solid var(--orange);
            cursor: pointer;
            font-size: 15px;
            transition: background 0.2s, transform 0.2s;
        }
        .cta-btn-ghost:hover {
            background: var(--orange-dim);
            transform: translateY(-2px);
        }

        /* ─── Icon box ─── */
        .icon-box {
            width: 52px; height: 52px;
            border-radius: 12px;
            background: var(--orange-dim);
            border: 1px solid rgba(234,118,0,0.3);
            display: flex; align-items: center; justify-content: center;
            flex-shrink: 0;
        }

        /* ─── Feature chip ─── */
        .feature-chip {
            display: flex;
            align-items: center;
            gap: 8px;
            background: var(--bg-panel);
            border: 1px solid var(--border);
            border-radius: 100px;
            padding: 8px 16px;
            font-size: 13px;
            color: #ccc;
        }

        /* ─── Sticky sidebar ─── */
        @media (min-width: 1024px) {
            .sticky-sidebar { position: sticky; top: 88px; }
        }

        /* ─── Modules connector line ─── */
        .module-connector {
            display: flex;
            flex-direction: column;
            align-items: center;
        }
        .connector-dot {
            width: 16px; height: 16px;
            border-radius: 50%;
            background: var(--orange);
            border: 3px solid var(--bg);
            box-shadow: 0 0 0 2px var(--orange);
            z-index: 2;
            flex-shrink: 0;
        }
        .connector-line {
            width: 2px;
            flex: 1;
            min-height: 24px;
            background: linear-gradient(to bottom, var(--orange), rgba(234,118,0,0.2));
        }

        /* mobile adjustments */
        @media (max-width: 640px) {
            .hero-title { font-size: 2.5rem; line-height: 1.1; }
        }