:root {
            --bg: #0a0f1e;
            --surface: #111827;
            --surface2: #1a2332;
            --surface3: #1e293b;
            --accent: #38bdf8;
            --accent2: #818cf8;
            --accent3: #f472b6;
            --gold: #f59e0b;
            --green: #10b981;
            --text: #e2e8f0;
            --text2: #94a3b8;
            --text3: #64748b;
            --border: rgba(255, 255, 255, 0.06);
            --glass: rgba(255, 255, 255, 0.03);
            --shadow-lg: 0 25px 60px rgba(0, 0, 0, 0.5);
            --shadow-md: 0 10px 30px rgba(0, 0, 0, 0.4);
            --radius-xl: 20px;
            --radius-lg: 16px;
            --radius-md: 12px;
            --radius-sm: 8px;
            --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }

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

        html {
            scroll-behavior: smooth;
            scroll-padding-top: 80px;
        }

        body {
            background: var(--bg);
            color: var(--text);
            font-family: 'Inter', sans-serif;
            line-height: 1.7;
            overflow-x: hidden;
            -webkit-tap-highlight-color: transparent;
            -webkit-font-smoothing: antialiased;
        }

        /* ============ SCROLLBAR ============ */
        ::-webkit-scrollbar {
            width: 6px;
        }

        ::-webkit-scrollbar-track {
            background: var(--bg);
        }

        ::-webkit-scrollbar-thumb {
            background: var(--surface3);
            border-radius: 10px;
        }

        ::-webkit-scrollbar-thumb:hover {
            background: var(--accent);
        }

        /* ============ PARTICLES BG ============ */
        .particles-bg {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            pointer-events: none;
            z-index: 0;
            opacity: 0.4;
        }

        .particle {
            position: absolute;
            border-radius: 50%;
            animation: floatUp linear infinite;
        }

        @keyframes floatUp {
            0% {
                transform: translateY(105vh) scale(0);
                opacity: 0;
            }

            10% {
                opacity: 1;
            }

            90% {
                opacity: 1;
            }

            100% {
                transform: translateY(-10vh) scale(1.4);
                opacity: 0;
            }
        }

        /* ============ TOP NAV ============ */
        .topnav {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            z-index: 1000;
            background: rgba(10, 15, 30, 0.8);
            backdrop-filter: blur(20px);
            -webkit-backdrop-filter: blur(20px);
            border-bottom: 1px solid var(--border);
            padding: 0 20px;
            height: 64px;
            display: flex;
            align-items: center;
            justify-content: space-between;
            transition: var(--transition);
        }

        .topnav.scrolled {
            box-shadow: 0 4px 30px rgba(0, 0, 0, 0.5);
            background: rgba(10, 15, 30, 0.95);
        }

        .nav-logo {
            display: flex;
            align-items: center;
            gap: 10px;
            font-weight: 800;
            font-size: 1.3rem;
            letter-spacing: -0.5px;
            text-decoration: none;
            color: white;
            z-index: 1001;
        }

        .nav-logo .icon-wrap {
            width: 38px;
            height: 38px;
            border-radius: 10px;
            background: linear-gradient(135deg, var(--accent), var(--accent2));
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.1rem;
            color: white;
            box-shadow: 0 4px 15px rgba(56, 189, 248, 0.35);
        }

        .nav-links {
            display: flex;
            align-items: center;
            gap: 8px;
            list-style: none;
        }

        .nav-links a {
            color: var(--text2);
            text-decoration: none;
            padding: 8px 16px;
            border-radius: 25px;
            font-weight: 500;
            font-size: 0.9rem;
            transition: var(--transition);
            white-space: nowrap;
        }

        .nav-links a:hover,
        .nav-links a.active {
            color: white;
            background: var(--glass);
        }

        .nav-cta {
            background: var(--accent) !important;
            color: #0a0f1e !important;
            font-weight: 600 !important;
            padding: 9px 20px !important;
            border-radius: 25px !important;
            box-shadow: 0 4px 18px rgba(56, 189, 248, 0.3);
        }

        .nav-cta:hover {
            box-shadow: 0 6px 25px rgba(56, 189, 248, 0.5) !important;
            transform: translateY(-2px);
        }

        /* Hamburger */
        .hamburger {
            display: none;
            flex-direction: column;
            gap: 5px;
            cursor: pointer;
            z-index: 1001;
            padding: 8px;
            background: none;
            border: none;
        }

        .hamburger span {
            width: 26px;
            height: 2.5px;
            background: white;
            border-radius: 4px;
            transition: var(--transition);
            display: block;
        }

        .hamburger.active span:nth-child(1) {
            transform: rotate(45deg) translate(5px, 5px);
        }

        .hamburger.active span:nth-child(2) {
            opacity: 0;
        }

        .hamburger.active span:nth-child(3) {
            transform: rotate(-45deg) translate(5px, -5px);
        }

        /* Mobile Nav */
        .mobile-nav {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: rgba(10, 15, 30, 0.98);
            backdrop-filter: blur(30px);
            -webkit-backdrop-filter: blur(30px);
            z-index: 999;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            gap: 20px;
            transform: translateY(-100%);
            transition: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
            opacity: 0;
            pointer-events: none;
        }

        .mobile-nav.open {
            transform: translateY(0);
            opacity: 1;
            pointer-events: all;
        }

        .mobile-nav a {
            color: white;
            text-decoration: none;
            font-size: 1.3rem;
            font-weight: 600;
            padding: 14px 30px;
            border-radius: 30px;
            transition: var(--transition);
        }

        .mobile-nav a:hover {
            background: var(--glass);
        }

        /* ============ HERO ============ */
        .hero {
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
            text-align: center;
            padding: 100px 30px 60px;
            position: relative;
            z-index: 1;
            background:
                radial-gradient(ellipse at 30% 20%, rgba(56, 189, 248, 0.08) 0%, transparent 60%),
                radial-gradient(ellipse at 70% 60%, rgba(129, 140, 248, 0.07) 0%, transparent 60%),
                radial-gradient(ellipse at 50% 80%, rgba(244, 114, 182, 0.05) 0%, transparent 50%),
                var(--bg);
        }

        .hero-badge {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: var(--glass);
            border: 1px solid var(--border);
            padding: 8px 18px;
            border-radius: 30px;
            font-size: 0.85rem;
            font-weight: 500;
            color: var(--accent);
            margin-bottom: 24px;
            animation: fadeInDown 0.7s ease;
        }

        .hero-badge .dot {
            width: 8px;
            height: 8px;
            border-radius: 50%;
            background: var(--green);
            animation: pulse-dot 2s infinite;
        }

        @keyframes pulse-dot {

            0%,
            100% {
                box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.6);
            }

            50% {
                box-shadow: 0 0 0 12px rgba(16, 185, 129, 0);
            }
        }

        @keyframes fadeInDown {
            from {
                opacity: 0;
                transform: translateY(-20px);
            }

            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        .hero h1 {
            font-size: clamp(2.2rem, 5vw, 4.2rem);
            font-weight: 900;
            letter-spacing: -1.5px;
            line-height: 1.15;
            margin-bottom: 16px;
            animation: fadeInDown 0.7s ease 0.1s both;
        }

        .hero h1 .gradient-text {
            background: linear-gradient(135deg, var(--accent), var(--accent2), var(--accent3));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        .hero p {
            max-width: 650px;
            font-size: 1.1rem;
            color: var(--text2);
            margin-bottom: 32px;
            animation: fadeInDown 0.7s ease 0.2s both;
            line-height: 1.8;
        }

        .hero-buttons {
            display: flex;
            gap: 14px;
            flex-wrap: wrap;
            justify-content: center;
            animation: fadeInDown 0.7s ease 0.3s both;
        }

        .btn {
            padding: 14px 30px;
            border-radius: 50px;
            font-weight: 600;
            font-size: 0.95rem;
            cursor: pointer;
            border: none;
            transition: var(--transition);
            text-decoration: none;
            display: inline-flex;
            align-items: center;
            gap: 8px;
            letter-spacing: -0.2px;
        }

        .btn-primary {
            background: var(--accent);
            color: #0a0f1e;
            box-shadow: 0 8px 30px rgba(56, 189, 248, 0.35);
        }

        .btn-primary:hover {
            transform: translateY(-3px);
            box-shadow: 0 12px 40px rgba(56, 189, 248, 0.5);
        }

        .btn-outline {
            background: transparent;
            color: white;
            border: 2px solid rgba(255, 255, 255, 0.2);
        }

        .btn-outline:hover {
            border-color: var(--accent);
            background: rgba(56, 189, 248, 0.08);
            transform: translateY(-3px);
        }

        /* ============ STATS ROW ============ */
        .stats-row {
            display: flex;
            gap: 30px;
            flex-wrap: wrap;
            justify-content: center;
            margin-top: 50px;
            animation: fadeInDown 0.7s ease 0.4s both;
        }

        .stat-item {
            text-align: center;
            padding: 20px 28px;
            background: var(--glass);
            border-radius: var(--radius-lg);
            border: 1px solid var(--border);
            min-width: 120px;
        }

        .stat-item .num {
            font-size: 2rem;
            font-weight: 800;
            background: linear-gradient(135deg, var(--accent), var(--accent2));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        .stat-item .lbl {
            font-size: 0.8rem;
            color: var(--text3);
            text-transform: uppercase;
            letter-spacing: 1px;
            margin-top: 4px;
        }

        /* ============ CONTAINER ============ */
        .container {
            max-width: 1100px;
            margin: auto;
            padding: 40px 20px;
            position: relative;
            z-index: 1;
        }

        .section-header {
            text-align: center;
            margin-bottom: 50px;
        }

        .section-header .tag {
            display: inline-block;
            background: rgba(56, 189, 248, 0.1);
            color: var(--accent);
            padding: 6px 16px;
            border-radius: 20px;
            font-size: 0.8rem;
            font-weight: 600;
            letter-spacing: 1px;
            text-transform: uppercase;
            margin-bottom: 12px;
        }

        .section-header h2 {
            font-size: clamp(1.8rem, 4vw, 2.6rem);
            font-weight: 800;
            letter-spacing: -1px;
            margin-bottom: 10px;
        }

        .section-header p {
            color: var(--text2);
            max-width: 550px;
            margin: auto;
            font-size: 0.95rem;
        }

        /* ============ SEARCH ============ */
        .search-wrap {
            max-width: 500px;
            margin: 0 auto 40px;
            position: relative;
        }

        .search-wrap input {
            width: 100%;
            padding: 15px 20px 15px 48px;
            border-radius: 50px;
            border: 2px solid var(--border);
            background: var(--surface);
            color: white;
            font-size: 0.95rem;
            font-family: 'Inter', sans-serif;
            transition: var(--transition);
            outline: none;
        }

        .search-wrap input:focus {
            border-color: var(--accent);
            box-shadow: 0 0 0 8px rgba(56, 189, 248, 0.06);
        }

        .search-wrap input::placeholder {
            color: var(--text3);
        }

        .search-wrap .search-icon {
            position: absolute;
            left: 18px;
            top: 50%;
            transform: translateY(-50%);
            color: var(--text3);
            font-size: 1rem;
            pointer-events: none;
        }

        /* ============ PHASE CARD ============ */
        .phase-card {
            background: var(--surface);
            border-radius: var(--radius-xl);
            margin-bottom: 16px;
            overflow: hidden;
            border: 1px solid var(--border);
            transition: var(--transition);
            box-shadow: var(--shadow-md);
        }

        .phase-card:hover {
            border-color: rgba(255, 255, 255, 0.12);
        }

        .phase-card.highlight {
            border-color: var(--accent);
            box-shadow: 0 0 0 4px rgba(56, 189, 248, 0.08);
        }

        .phase-btn {
            width: 100%;
            padding: 18px 22px;
            border: none;
            background: transparent;
            color: white;
            font-size: 1.05rem;
            font-weight: 600;
            cursor: pointer;
            text-align: left;
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 14px;
            transition: var(--transition);
            letter-spacing: -0.3px;
        }

        .phase-btn:hover {
            background: var(--glass);
        }

        .phase-btn .phase-num {
            flex-shrink: 0;
            width: 40px;
            height: 40px;
            border-radius: 10px;
            background: linear-gradient(135deg, var(--accent), var(--accent2));
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 700;
            font-size: 0.9rem;
            color: #0a0f1e;
        }

        .phase-btn .phase-info {
            flex: 1;
            display: flex;
            flex-direction: column;
            gap: 2px;
        }

        .phase-btn .phase-info small {
            font-weight: 400;
            font-size: 0.78rem;
            color: var(--text3);
        }

        .phase-btn .phase-arrow {
            font-size: 0.8rem;
            color: var(--text3);
            transition: var(--transition);
            flex-shrink: 0;
        }

        .phase-card.open .phase-arrow {
            transform: rotate(180deg);
            color: var(--accent);
        }

        .phase-content {
            display: none;
            padding: 0 22px 20px;
            animation: slideDown 0.35s ease;
        }

        @keyframes slideDown {
            from {
                opacity: 0;
                transform: translateY(-10px);
            }

            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        .phase-card.open .phase-content {
            display: block;
        }

        /* ============ MODULE ============ */
        .module {
            margin-bottom: 12px;
            border-radius: var(--radius-md);
            overflow: hidden;
            background: var(--surface2);
            border: 1px solid var(--border);
        }

        .module-btn {
            width: 100%;
            padding: 14px 18px;
            background: transparent;
            border: none;
            color: white;
            cursor: pointer;
            font-weight: 500;
            font-size: 0.9rem;
            text-align: left;
            display: flex;
            align-items: center;
            justify-content: space-between;
            transition: var(--transition);
            letter-spacing: -0.2px;
        }

        .module-btn:hover {
            background: var(--glass);
        }

        .module-btn .mod-icon {
            width: 32px;
            height: 32px;
            border-radius: 8px;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-right: 10px;
            font-size: 0.8rem;
            flex-shrink: 0;
        }

        .mod-icon.python {
            background: rgba(55, 118, 179, 0.3);
            color: #5b9bd5;
        }

        .mod-icon.math {
            background: rgba(245, 158, 11, 0.3);
            color: #f59e0b;
        }

        .mod-icon.data {
            background: rgba(16, 185, 129, 0.3);
            color: #10b981;
        }

        .mod-icon.ml {
            background: rgba(236, 72, 153, 0.3);
            color: #ec4899;
        }

        .mod-icon.dl {
            background: rgba(129, 140, 248, 0.3);
            color: #818cf8;
        }

        .module-btn .mod-chevron {
            font-size: 0.7rem;
            color: var(--text3);
            transition: var(--transition);
        }

        .module.open .mod-chevron {
            transform: rotate(180deg);
            color: var(--accent);
        }

        .module-content {
            display: none;
            padding: 0 18px 16px 60px;
            animation: slideDown 0.3s ease;
        }

        .module.open .module-content {
            display: block;
        }

        .module-content ul {
            list-style: none;
            padding: 0;
        }

        .module-content li {
            padding: 10px 14px;
            margin-bottom: 6px;
            border-radius: var(--radius-sm);
            background: var(--surface);
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 10px;
            transition: var(--transition);
            border: 1px solid transparent;
            font-size: 0.88rem;
            flex-wrap: wrap;
        }

        .module-content li:hover {
            border-color: var(--border);
            background: var(--surface3);
        }

        .module-content li .topic-name {
            flex: 1;
            min-width: 140px;
            font-weight: 500;
        }

        .module-content li .official-link {
            display: inline-flex;
            align-items: center;
            gap: 5px;
            padding: 6px 12px;
            border-radius: 20px;
            background: rgba(56, 189, 248, 0.1);
            color: var(--accent);
            text-decoration: none;
            font-size: 0.75rem;
            font-weight: 500;
            white-space: nowrap;
            transition: var(--transition);
            flex-shrink: 0;
        }

        .module-content li .official-link:hover {
            background: rgba(56, 189, 248, 0.2);
            color: white;
            transform: scale(1.03);
        }

        .module-content li .official-link i {
            font-size: 0.65rem;
        }

        /* ============ TIMELINE ============ */
        .timeline-section {
            margin-top: 60px;
        }

        .timeline {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
            gap: 16px;
            margin-top: 30px;
        }

        .step {
            background: var(--surface);
            padding: 24px 20px;
            border-radius: var(--radius-lg);
            text-align: center;
            transition: var(--transition);
            border: 1px solid var(--border);
            position: relative;
            overflow: hidden;
        }

        .step::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 3px;
            background: linear-gradient(90deg, var(--accent), var(--accent2));
            border-radius: 0 0 4px 4px;
        }

        .step:hover {
            transform: translateY(-8px);
            box-shadow: var(--shadow-lg);
            border-color: rgba(255, 255, 255, 0.15);
        }

        .step .step-num {
            font-size: 2.5rem;
            font-weight: 900;
            background: linear-gradient(135deg, var(--accent), var(--accent2));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            opacity: 0.7;
        }

        .step h3 {
            font-size: 0.9rem;
            font-weight: 700;
            margin: 6px 0;
            letter-spacing: -0.3px;
        }

        .step p {
            font-size: 0.78rem;
            color: var(--text2);
            line-height: 1.5;
        }

        /* ============ RESOURCE SECTION ============ */
        .resources-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 16px;
            margin-top: 30px;
        }

        .resource-card {
            background: var(--surface);
            border-radius: var(--radius-lg);
            padding: 22px;
            border: 1px solid var(--border);
            transition: var(--transition);
            text-decoration: none;
            color: var(--text);
            display: flex;
            align-items: flex-start;
            gap: 14px;
        }

        .resource-card:hover {
            transform: translateY(-5px);
            box-shadow: var(--shadow-lg);
            border-color: var(--accent);
        }

        .resource-card .res-icon {
            width: 44px;
            height: 44px;
            border-radius: 12px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.2rem;
            flex-shrink: 0;
        }

        .resource-card h4 {
            font-size: 0.95rem;
            font-weight: 600;
            margin-bottom: 4px;
        }

        .resource-card p {
            font-size: 0.78rem;
            color: var(--text3);
            line-height: 1.4;
        }

        /* ============ FOOTER ============ */
        .footer {
            padding: 50px 20px 30px;
            text-align: center;
            background: var(--surface);
            border-top: 1px solid var(--border);
            position: relative;
            z-index: 1;
        }

        .footer h2 {
            font-size: 1.6rem;
            font-weight: 700;
            margin-bottom: 8px;
            letter-spacing: -0.5px;
        }

        .footer .footer-tags {
            display: flex;
            flex-wrap: wrap;
            gap: 8px;
            justify-content: center;
            margin: 16px 0;
        }

        .footer .footer-tags span {
            background: var(--surface2);
            padding: 6px 14px;
            border-radius: 20px;
            font-size: 0.75rem;
            color: var(--text2);
            border: 1px solid var(--border);
        }

        .footer .copy {
            font-size: 0.75rem;
            color: var(--text3);
            margin-top: 16px;
        }

        /* ============ BACK TO TOP ============ */
        .back-to-top {
            position: fixed;
            bottom: 28px;
            right: 28px;
            width: 48px;
            height: 48px;
            border-radius: 50%;
            background: var(--accent);
            color: #0a0f1e;
            border: none;
            cursor: pointer;
            font-size: 1.1rem;
            z-index: 99;
            box-shadow: 0 8px 25px rgba(56, 189, 248, 0.4);
            transition: var(--transition);
            display: flex;
            align-items: center;
            justify-content: center;
            opacity: 0;
            pointer-events: none;
        }

        .back-to-top.visible {
            opacity: 1;
            pointer-events: all;
        }

        .back-to-top:hover {
            transform: translateY(-4px);
            box-shadow: 0 14px 35px rgba(56, 189, 248, 0.6);
        }

        /* ============ MOBILE ============ */
        @media (max-width: 768px) {
            .nav-links {
                display: none;
            }

            .hamburger {
                display: flex;
            }

            .hero {
                padding: 90px 16px 40px;
                min-height: auto;
            }

            .hero h1 {
                font-size: 2rem;
            }

            .hero p {
                font-size: 0.9rem;
            }

            .btn {
                padding: 12px 22px;
                font-size: 0.85rem;
            }

            .stats-row {
                gap: 12px;
            }

            .stat-item {
                padding: 14px 16px;
                min-width: 80px;
            }

            .stat-item .num {
                font-size: 1.4rem;
            }

            .phase-btn {
                padding: 14px 16px;
                font-size: 0.9rem;
            }

            .phase-btn .phase-num {
                width: 32px;
                height: 32px;
                font-size: 0.75rem;
                border-radius: 8px;
            }

            .module-btn {
                padding: 12px 14px;
                font-size: 0.82rem;
            }

            .module-content {
                padding: 0 10px 12px 14px;
            }

            .module-content li {
                font-size: 0.78rem;
                padding: 8px 10px;
                flex-direction: column;
                align-items: flex-start;
                gap: 6px;
            }

            .module-content li .official-link {
                font-size: 0.7rem;
                padding: 5px 10px;
            }

            .timeline {
                grid-template-columns: repeat(2, 1fr);
                gap: 10px;
            }

            .step {
                padding: 16px 12px;
            }

            .step .step-num {
                font-size: 1.8rem;
            }

            .resources-grid {
                grid-template-columns: 1fr;
            }

            .back-to-top {
                bottom: 16px;
                right: 16px;
                width: 40px;
                height: 40px;
            }

            .section-header h2 {
                font-size: 1.6rem;
            }
        }

        @media (max-width: 400px) {
            .hero h1 {
                font-size: 1.6rem;
            }

            .hero-buttons {
                flex-direction: column;
                width: 100%;
            }

            .btn {
                width: 100%;
                justify-content: center;
            }

            .stats-row {
                flex-direction: column;
                align-items: center;
            }

            .timeline {
                grid-template-columns: 1fr;
            }
        }