:root {
            --blue: #60a5fa;
            --blue-d: #3b82f6;
            --blue-l: rgba(96, 165, 250, 0.1);
            --blue-m: rgba(96, 165, 250, 0.2);
            --green: #34d399;
            --wa: #25d366;
            --tg: #229ED9;
            --text: #f1f5f9;
            --muted: #94a3b8;
            --border: rgba(255, 255, 255, 0.08);
            --bg: #020617;
            --card-bg: #0f172a;
            --white: #1e293b;
            --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.5);
            --shadow-h: 0 20px 25px -5px rgba(0, 0, 0, 0.7);
            --r: 20px;
            --r-s: 12px;
        }

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

        body {
            font-family: 'Plus Jakarta Sans', sans-serif;
            background: var(--bg);
            color: var(--text);
            line-height: 1.6;
            overflow-x: hidden;
            background-image: 
                radial-gradient(at 0% 0%, rgba(59, 130, 246, 0.03) 0px, transparent 50%),
                radial-gradient(at 100% 0%, rgba(147, 51, 234, 0.03) 0px, transparent 50%);
            background-attachment: fixed;
        }

        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }

        /* NAVIGATION */
        header {
            position: sticky;
            top: 0;
            z-index: 1000;
            background: rgba(15, 23, 42, 0.8);
            backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--border);
            transition: all 0.3s;
        }

        header.scrolled {
            background: rgba(15, 23, 42, 0.95);
            box-shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
        }

        nav {
            display: flex;
            justify-content: space-between;
            align-items: center;
            height: 80px;
        }

        .logo {
            font-size: 1.5rem;
            font-weight: 800;
            color: var(--blue);
            cursor: pointer;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .mock-nav-btn {
            padding: 8px 15px;
            border: none;
            background: transparent;
            color: var(--muted);
            font-weight: 600;
            font-size: 0.85rem;
            cursor: pointer;
            border-bottom: 2px solid transparent;
            white-space: nowrap;
            transition: 0.2s;
        }

        .mock-nav-btn.active {
            color: var(--blue);
            border-bottom-color: var(--blue);
        }

        .mock-nav-btn:hover {
            color: var(--blue);
        }

        .nav-links {
            display: flex;
            gap: 8px;
        }

        .nav-btn {
            padding: 8px 16px;
            border-radius: var(--r-s);
            font-size: 0.9rem;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.2s;
            border: none;
            background: transparent;
            color: var(--muted);
        }

        .nav-btn:hover {
            background: rgba(255, 255, 255, 0.05);
            color: var(--blue);
        }

        .nav-btn.active {
            background: var(--blue-d);
            color: white;
            box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
        }

        .mobile-menu-btn {
            display: none;
            flex-direction: column;
            gap: 6px;
            cursor: pointer;
            padding: 10px;
        }

        .mobile-menu-btn span {
            width: 24px;
            height: 2px;
            background: var(--text);
            transition: 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
        }

        .mobile-menu-btn.active span:nth-child(1) {
            transform: translateY(8px) rotate(45deg);
        }

        .mobile-menu-btn.active span:nth-child(2) {
            opacity: 0;
            transform: translateX(-20px);
        }

        .mobile-menu-btn.active span:nth-child(3) {
            transform: translateY(-8px) rotate(-45deg);
        }

        /* PAGE SYSTEM */
        .page {
            display: none;
            padding: 60px 0;
            background: var(--bg);
        }

        .page.active {
            display: block;
            animation: fadeIn 0.35s ease;
        }

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

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

        .back-btn-top {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            color: var(--blue);
            text-decoration: none;
            font-weight: 700;
            font-size: 0.9rem;
            margin-bottom: 20px;
            cursor: pointer;
            transition: 0.2s;
            background: rgba(59, 130, 246, 0.1);
            padding: 8px 16px;
            border-radius: 100px;
            border: 1px solid rgba(59, 130, 246, 0.2);
        }

        .back-btn-top:hover {
            background: var(--blue);
            color: white;
            transform: translateX(-5px);
        }

        /* HOME PAGE HERO */
        #page-home {
            padding: 0;
        }

        .hero {
            background: radial-gradient(circle at 50% -20%, #1e3a8a 0%, #020617 80%);
            color: white;
            padding: 140px 0 160px;
            position: relative;
            overflow: hidden;
            text-align: center;
        }

        .hero-bg-glow {
            position: absolute;
            width: 400px;
            height: 400px;
            background: radial-gradient(circle, rgba(37, 99, 235, 0.4) 0%, transparent 70%);
            border-radius: 50%;
            top: -100px;
            left: -100px;
            filter: blur(60px);
        }

        .hero-badge {
            display: inline-block;
            padding: 6px 16px;
            background: rgba(255, 255, 255, 0.1);
            border: 1px solid rgba(255, 255, 255, 0.2);
            border-radius: 100px;
            font-size: 0.85rem;
            font-weight: 600;
            margin-bottom: 24px;
        }

        .hero h1 {
            font-size: clamp(2.5rem, 8vw, 4.5rem);
            font-weight: 800;
            line-height: 1.1;
            margin-bottom: 24px;
        }

        .hero h1 span {
            background: linear-gradient(90deg, #60a5fa, #38bdf8);
            -webkit-background-clip: text;
            background-clip: text;
            -webkit-text-fill-color: transparent;
        }

        .hero p {
            font-size: 1.25rem;
            color: rgba(255, 255, 255, 0.8);
            max-width: 700px;
            margin: 0 auto 40px;
        }

        .hero-search {
            max-width: 600px;
            margin: 0 auto 40px;
            position: relative;
        }

        .hero-search input {
            width: 100%;
            padding: 18px 24px 18px 56px;
            border-radius: 16px;
            border: 1px solid rgba(255, 255, 255, 0.2);
            background: rgba(255, 255, 255, 0.05);
            backdrop-filter: blur(10px);
            color: var(--white);
            font-size: 1rem;
            outline: none;
            transition: all 0.3s;
        }

        .hero-search input:focus {
            background: rgba(255, 255, 255, 0.1);
            border-color: rgba(255, 255, 255, 0.4);
        }

        .hero-search svg {
            position: absolute;
            left: 20px;
            top: 50%;
            transform: translateY(-50%);
            color: rgba(255, 255, 255, 0.5);
        }

        .hero-ctas {
            display: flex;
            justify-content: center;
            gap: 16px;
            margin-bottom: 60px;
            flex-wrap: wrap;
        }

        .btn {
            padding: 14px 28px;
            border-radius: 12px;
            font-weight: 700;
            text-decoration: none;
            transition: all 0.2s;
            cursor: pointer;
            display: inline-flex;
            align-items: center;
            gap: 10px;
            border: none;
            font-family: inherit;
        }

        .btn-wa {
            background: var(--wa);
            color: white;
        }

        .btn-tg {
            background: var(--tg);
            color: white;
        }

        .btn-wa:hover,
        .btn-tg:hover {
            transform: translateY(-2px);
            box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
        }

        .hero-stats {
            display: flex;
            justify-content: center;
            gap: 60px;
            border-top: 1px solid rgba(255, 255, 255, 0.1);
            padding-top: 40px;
        }

        .stat-item h3 {
            font-size: 2rem;
            font-weight: 800;
        }

        .stat-item p {
            font-size: 0.9rem;
            color: rgba(255, 255, 255, 0.6);
            margin: 0;
        }

        /* GRID LAYOUTS */
        .grid-7 {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 24px;
            padding: 80px 0;
        }

        .card {
            background: rgba(30, 41, 59, 0.4);
            padding: 32px;
            border-radius: var(--r);
            border: 1px solid var(--border);
            transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
            cursor: pointer;
            position: relative;
            display: flex;
            flex-direction: column;
            gap: 16px;
            backdrop-filter: blur(5px);
        }

        .card:hover {
            transform: translateY(-12px) scale(1.02);
            background: rgba(30, 41, 59, 0.8);
            box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
            border-color: var(--blue);
        }

        .card-icon {
            width: 56px;
            height: 56px;
            background: var(--blue-l);
            border-radius: 16px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.5rem;
        }

        .card h3 {
            font-size: 1.25rem;
            font-weight: 700;
        }

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

        .card-tags {
            display: flex;
            gap: 8px;
        }

        .card-tag {
            padding: 4px 10px;
            background: rgba(255, 255, 255, 0.05);
            border-radius: 6px;
            font-size: 0.75rem;
            font-weight: 700;
            color: var(--blue);
        }

        .card-highlight {
            border: 2px solid var(--blue);
            background: linear-gradient(to bottom right, #ffffff, #f0f7ff);
        }

        .card-arrow {
            position: absolute;
            bottom: 32px;
            right: 32px;
            color: var(--blue);
            opacity: 0;
            transition: 0.3s;
        }

        .card:hover .card-arrow {
            opacity: 1;
            transform: translateX(5px);
        }

        /* FOOTER */
        footer {
            background: #020617;
            color: var(--text);
            padding: 100px 0 40px;
            border-top: 1px solid var(--border);
        }

        .footer-content {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 40px;
            margin-bottom: 60px;
        }

        .footer-about p {
            color: rgba(255, 255, 255, 0.5);
            font-size: 0.9rem;
            margin-top: 16px;
            max-width: 300px;
        }

        .footer-links h4 {
            margin-bottom: 24px;
            font-weight: 700;
        }

        .footer-links ul {
            list-style: none;
        }

        .footer-links li {
            margin-bottom: 12px;
        }

        .footer-links a {
            color: rgba(255, 255, 255, 0.5);
            text-decoration: none;
            font-size: 0.9rem;
            transition: 0.2s;
        }

        .footer-links a:hover {
            color: var(--white);
        }

        .footer-bottom {
            text-align: center;
            border-top: 1px solid rgba(255, 255, 255, 0.1);
            padding-top: 40px;
            color: rgba(255, 255, 255, 0.3);
            font-size: 0.85rem;
        }

        /* MOBILE */
        @media (max-width: 768px) {
            .nav-links {
                display: none;
                position: absolute;
                top: 80px;
                left: 0;
                width: 100%;
                background: rgba(15, 23, 42, 0.98);
                backdrop-filter: blur(20px);
                flex-direction: column;
                padding: 20px;
                gap: 5px;
                border-bottom: 1px solid var(--border);
                box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
                animation: slideDown 0.3s ease forwards;
            }

            @keyframes slideDown {
                from { opacity: 0; transform: translateY(-10px); }
                to { opacity: 1; transform: translateY(0); }
            }

            .nav-links.active {
                display: flex;
            }

            .nav-btn {
                width: 100%;
                text-align: left;
                padding: 15px 20px;
                font-size: 1rem;
                border-radius: 12px;
            }

            .mobile-menu-btn {
                display: flex;
            }

            .footer-content {
                grid-template-columns: 1fr 1fr;
            }

            .hero h1 {
                font-size: 2.2rem;
            }

            .container {
                padding: 0 20px;
            }

            .hero-ctas {
                flex-direction: column;
            }

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

            .stat-item h3 {
                font-size: 1.5rem;
            }
        }

        /* MOCK TEST UI */
        .mock-test-container {
            background: #0f172a;
            border-radius: var(--r);
            border: 1px solid var(--border);
            box-shadow: var(--shadow-h);
            overflow: hidden;
            max-width: 900px;
            margin: 0 auto;
        }

        .test-header {
            background: var(--text);
            color: white;
            padding: 20px 30px;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .test-timer {
            font-family: 'DM Mono', monospace;
            font-size: 1.25rem;
            background: rgba(255, 255, 255, 0.1);
            padding: 8px 16px;
            border-radius: 8px;
        }

        .test-body {
            padding: 40px;
        }

        .test-options {
            display: grid;
            gap: 12px;
            margin: 30px 0;
        }

        .test-option {
            padding: 16px 24px;
            border: 1px solid var(--border);
            background: rgba(255, 255, 255, 0.03);
            border-radius: 12px;
            cursor: pointer;
            transition: all 0.2s;
            font-weight: 600;
            color: var(--text);
            text-align: left;
        }

        .test-option:hover {
            border-color: var(--blue);
            background: rgba(96, 165, 250, 0.1);
        }

        .test-option.selected {
            border-color: var(--blue);
            background: var(--blue-d);
            color: white;
            box-shadow: 0 0 20px rgba(59, 130, 246, 0.3);
        }

        /* CODING SECTION */
        .code-editor {
            background: #010409;
            border-radius: 12px;
            padding: 0;
            color: #e2e8f0;
            font-family: 'DM Mono', monospace;
            font-size: 0.9rem;
            position: relative;
            margin-top: 20px;
            border: 1px solid rgba(255, 255, 255, 0.1);
            overflow: hidden;
            box-shadow: 0 10px 30px rgba(0,0,0,0.5);
        }

        .code-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            background: rgba(255, 255, 255, 0.03);
            padding: 10px 20px;
            border-bottom: 1px solid rgba(255, 255, 255, 0.05);
        }

        .code-header span {
            font-size: 0.75rem;
            font-weight: 700;
            color: var(--muted);
            text-transform: uppercase;
            letter-spacing: 1px;
        }

        .code-header button {
            background: rgba(59, 130, 246, 0.1);
            border: 1px solid rgba(59, 130, 246, 0.2);
            color: var(--blue);
            padding: 4px 10px;
            border-radius: 6px;
            font-size: 0.75rem;
            cursor: pointer;
            transition: 0.2s;
        }

        .code-header button:hover {
            background: var(--blue);
            color: white;
        }

        .code-editor pre {
            padding: 20px;
            overflow-x: auto;
            margin: 0;
            line-height: 1.5;
        }

        .code-editor code {
            color: #d1d5db;
        }

        .input-guide-content {
            animation: fadeIn 0.4s ease;
        }

        @media (max-width: 768px) {
            .input-guide-content .card {
                padding: 20px !important;
            }
        }

        /* ... more styles will be added as we build ... */

        .sc-tab-btn {
            padding: 12px 20px;
            background: transparent;
            border: none;
            color: var(--muted);
            font-weight: 700;
            font-size: 0.9rem;
            cursor: pointer;
            transition: all 0.3s;
            border-bottom: 2px solid transparent;
            text-transform: uppercase;
            letter-spacing: 1px;
        }

        .sc-tab-btn:hover {
            color: var(--text);
            background: rgba(255,255,255,0.05);
        }

        .sc-tab-btn.active {
            color: var(--blue);
            border-bottom-color: var(--blue);
            background: rgba(59, 130, 246, 0.05);
        }

        /* ===== STANDARDIZED TITLES ===== */
        .section-title {
            font-size: 2.5rem;
            font-weight: 800;
            margin-bottom: 12px;
            text-align: center;
        }

        .section-desc {
            text-align: center;
            color: var(--muted);
            margin-bottom: 32px;
            font-size: 1rem;
            max-width: 700px;
            margin-left: auto;
            margin-right: auto;
        }

        /* ===== STICKY LANGUAGE NAV BAR ===== */
        .sticky-tabs-wrapper {
            position: sticky;
            top: 64px; /* Matches nav height */
            z-index: 100;
            background: var(--bg);
            margin-bottom: 36px;
            padding: 10px 0;
            display: flex;
            justify-content: center;
            transition: all 0.3s;
        }

        /* Glass effect when scrolling */
        .scrolled .sticky-tabs-wrapper {
            background: rgba(10, 15, 30, 0.85);
            backdrop-filter: blur(12px);
            border-bottom: 1px solid rgba(255,255,255,0.05);
        }

        .lang-tabs-container {
            display: inline-flex;
            background: rgba(30, 41, 59, 0.5);
            border: 1px solid rgba(255,255,255,0.1);
            border-radius: 50px;
            padding: 6px;
            gap: 4px;
            flex-wrap: nowrap;
            overflow-x: auto;
            max-width: 100%;
            scrollbar-width: none;
            -webkit-overflow-scrolling: touch;
        }

        .lang-tabs-container::-webkit-scrollbar {
            display: none;
        }

        .lang-tab-btn {
            padding: 10px 20px;
            border-radius: 50px;
            font-size: 0.95rem;
            font-weight: 700;
            cursor: pointer;
            transition: all 0.25s ease;
            border: none;
            background: transparent;
            color: var(--muted);
            white-space: nowrap;
            display: inline-flex;
            align-items: center;
            gap: 8px;
        }

        .lang-tab-btn:hover {
            color: var(--text);
            background: rgba(255,255,255,0.05);
        }

        .lang-tab-btn.active {
            background: var(--blue-d);
            color: white;
            box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
        }

        @media (max-width: 768px) {
            .section-title {
                font-size: 1.8rem;
            }
            .section-desc {
                font-size: 0.9rem;
                margin-bottom: 24px;
            }
            .sticky-tabs-wrapper {
                top: 64px;
                padding: 8px 0;
            }
            .lang-tab-btn {
                padding: 8px 14px;
                font-size: 0.85rem;
                gap: 6px;
            }
        }

        .badge {
            background: #ef4444;
            color: white;
            font-size: 10px;
            padding: 2px 6px;
            border-radius: 10px;
            margin-left: 5px;
            font-weight: 800;
            vertical-align: middle;
            text-transform: uppercase;
        }

        /* PREMIUM COMPILER STYLES */
        .compiler-wrapper {
            background: #0d1117;
            border-radius: 12px;
            border: 1px solid #30363d;
            overflow: hidden;
            display: flex;
            flex-direction: column;
            box-shadow: 0 20px 50px rgba(0,0,0,0.6);
            height: 100%;
        }

        .compiler-header-bar {
            background: #161b22;
            padding: 10px 15px;
            display: flex;
            justify-content: space-between;
            align-items: center;
            border-bottom: 1px solid #30363d;
            flex-wrap: wrap;
            gap: 10px;
        }

        .compiler-file-info {
            display: flex;
            align-items: center;
            gap: 12px;
            font-family: 'DM Mono', monospace;
            font-size: 0.85rem;
            color: #8b949e;
        }

        .compiler-file-tab {
            background: #0d1117;
            padding: 6px 14px;
            border-radius: 6px 6px 0 0;
            border-top: 2px solid var(--blue);
            color: #f0f6fc;
            display: flex;
            align-items: center;
            gap: 8px;
            font-size: 0.85rem;
        }

        .undo-redo-btns {
            display: flex;
            gap: 6px;
        }

        .icon-btn {
            background: transparent;
            border: 1px solid #30363d;
            color: #8b949e;
            padding: 6px;
            border-radius: 6px;
            cursor: pointer;
            transition: 0.2s;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .icon-btn:hover {
            color: var(--blue);
            background: rgba(59, 130, 246, 0.1);
            border-color: var(--blue);
        }

        .compiler-actions {
            display: flex;
            gap: 10px;
            align-items: center;
        }

        .btn-compile {
            background: #238636;
            color: white;
            border: none;
            padding: 8px 18px;
            border-radius: 6px;
            font-size: 0.85rem;
            font-weight: 700;
            cursor: pointer;
            transition: all 0.2s;
            display: flex;
            align-items: center;
            gap: 8px;
            white-space: nowrap;
        }

        .btn-compile:hover {
            background: #2ea043;
        }

        .compiler-main {
            display: flex;
            flex: 1;
            overflow: hidden;
            position: relative;
        }

        .line-numbers-sidebar {
            background: #0d1117;
            color: #484f58;
            padding: 15px 8px;
            text-align: right;
            font-family: 'DM Mono', monospace;
            font-size: 0.85rem;
            user-select: none;
            border-right: 1px solid #30363d;
            min-width: 40px;
            overflow: hidden;
        }

        .real-editor {
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: transparent;
            border: none;
            color: transparent;
            caret-color: #e6edf3;
            font-family: 'DM Mono', monospace !important;
            font-size: 0.95rem;
            line-height: 1.6;
            padding: 15px;
            padding-left: 10px;
            resize: none;
            outline: none;
            overflow-y: auto;
            tab-size: 4;
            white-space: pre;
            z-index: 2;
        }

        .code-highlight-layer {
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            font-family: 'DM Mono', monospace !important;
            font-size: 0.95rem;
            line-height: 1.6;
            padding: 15px;
            padding-left: 10px;
            white-space: pre;
            overflow-y: auto;
            pointer-events: none;
            z-index: 1;
            color: #e6edf3;
            tab-size: 4;
            word-wrap: normal;
            overflow-wrap: normal;
        }

        .editor-area {
            position: relative;
            flex: 1;
            overflow: hidden;
            background: #0d1117;
        }

        /* Syntax Highlight Colors (VS Code Dark+ theme) */
        .hl-keyword { color: #c586c0; }
        .hl-builtin { color: #4ec9b0; }
        .hl-string { color: #ce9178; }
        .hl-comment { color: #6a9955; font-style: italic; }
        .hl-number { color: #b5cea8; }
        .hl-function { color: #dcdcaa; }
        .hl-operator { color: #d4d4d4; }
        .hl-type { color: #4ec9b0; }
        .hl-decorator { color: #d7ba7d; }
        .hl-boolean { color: #569cd6; }
        .hl-self { color: #9cdcfe; }


        .compiler-console {
            background: #010409;
            border-top: 1px solid #30363d;
            padding: 15px 20px;
            font-family: 'DM Mono', monospace;
            font-size: 0.85rem;
            min-height: 120px;
            max-height: 200px;
            overflow-y: auto;
        }

        .compile-spinner {
            display: inline-block;
            width: 14px;
            height: 14px;
            border: 2px solid rgba(139,148,158,0.3);
            border-top-color: #60a5fa;
            border-radius: 50%;
            animation: spin 0.6s linear infinite;
        }

        @keyframes spin {
            to { transform: rotate(360deg); }
        }

        /* ===== MOBILE RESPONSIVENESS FOR MOCK TEST ===== */

        /* Tablet & small desktop */
        @media (max-width: 1024px) {
            #mock-question-area-inner {
                display: flex !important;
                flex-direction: column !important;
                height: auto !important;
                gap: 15px !important;
            }
            .mock-question-desc {
                width: 100% !important;
                max-height: 300px;
                overflow-y: auto;
                padding: 20px !important;
            }
            .mock-question-editor,
            .compiler-wrapper {
                width: 100% !important;
                height: 550px !important;
            }
        }

        /* Phones */
        @media (max-width: 768px) {
            .test-body {
                padding: 12px !important;
            }
            #mock-question-area-inner {
                gap: 10px !important;
            }
            .mock-question-desc {
                max-height: 250px;
                padding: 15px !important;
                border-radius: 8px !important;
            }
            .mock-question-desc h3 {
                font-size: 1.15rem !important;
            }
            .mock-question-desc p {
                font-size: 0.85rem !important;
            }
            .mock-question-editor,
            .compiler-wrapper {
                height: 480px !important;
                border-radius: 8px !important;
            }
            .compiler-header-bar {
                padding: 8px 10px;
                gap: 8px;
            }
            .compiler-file-tab {
                padding: 5px 10px;
                font-size: 0.75rem;
            }
            .icon-btn {
                padding: 4px;
            }
            .icon-btn svg {
                width: 15px;
                height: 15px;
            }
            .btn-compile {
                padding: 6px 12px;
                font-size: 0.8rem;
            }
            .line-numbers-sidebar {
                min-width: 30px;
                padding: 10px 5px;
                font-size: 0.75rem;
            }
            .real-editor,
            .code-highlight-layer {
                font-size: 0.8rem;
                padding: 10px 8px;
            }
            .compiler-console {
                padding: 10px 12px;
                font-size: 0.75rem;
                min-height: 80px;
                max-height: 150px;
            }
            #mock-section-nav {
                padding: 8px 15px !important;
                gap: 6px !important;
            }
            .mock-nav-btn {
                font-size: 0.75rem !important;
                padding: 6px 10px !important;
            }
            #mock-timer {
                font-size: 1rem !important;
            }
        }

        /* Very small phones */
        @media (max-width: 480px) {
            .mock-question-desc {
                max-height: 200px;
                padding: 12px !important;
            }
            .mock-question-editor,
            .compiler-wrapper {
                height: 420px !important;
            }
            .compiler-header-bar {
                flex-direction: column;
                align-items: stretch;
            }
            .compiler-header-bar > div {
                justify-content: space-between;
            }
            .compiler-actions {
                width: 100%;
                justify-content: space-between;
            }
            .undo-redo-btns {
                gap: 4px;
            }
            .real-editor,
            .code-highlight-layer {
                font-size: 0.75rem;
                line-height: 1.5;
            }
            .line-numbers-sidebar {
                display: none;
            }
        }


        /* ===== FULLSCREEN CODING MODE ===== */
        .coding-fullscreen {
            position: fixed !important;
            top: 0;
            left: 0;
            width: 100vw !important;
            height: 100vh !important;
            z-index: 9999;
            background: #0d1117;
            border-radius: 0 !important;
            border: none !important;
            margin: 0 !important;
        }

        .coding-fullscreen .compiler-main {
            flex: 1;
        }

        .coding-fullscreen .real-editor,
        .coding-fullscreen .code-highlight-layer {
            font-size: 1.1rem;
        }

        /* ============================================
           🚀 COMPREHENSIVE MOBILE RESPONSIVE STYLES
           Covers: Nav, Hero, Dashboard, Coding,
           Scenario, Mock Test, Footer & All Grids
        ============================================ */

        /* ---- TABLET (≤1024px) ---- */
        @media (max-width: 1024px) {
            #mock-question-area-inner {
                display: flex !important;
                flex-direction: column !important;
                height: auto !important;
                gap: 15px !important;
            }
            .mock-question-desc {
                width: 100% !important;
                max-height: 300px;
                overflow-y: auto;
                padding: 20px !important;
            }
            .mock-question-editor,
            .compiler-wrapper {
                width: 100% !important;
                height: 550px !important;
            }

            /* Dashboard grid 2-col on tablet */
            .footer-content {
                grid-template-columns: 1fr 1fr;
                gap: 30px;
            }

            /* Scenario grid: sample input/output side by side still ok */
        }

        /* ---- PHONES (≤768px) ---- */
        @media (max-width: 768px) {

            /* === NAV === */
            nav {
                height: 64px;
            }

            .logo {
                font-size: 1.2rem;
            }

            .nav-links {
                display: none;
                position: fixed;
                top: 64px;
                left: 0;
                width: 100%;
                height: calc(100vh - 64px);
                background: rgba(10, 15, 30, 0.98);
                backdrop-filter: blur(20px);
                flex-direction: column;
                padding: 20px 16px;
                gap: 4px;
                border-top: 1px solid var(--border);
                overflow-y: auto;
                z-index: 999;
                animation: slideDown 0.3s ease forwards;
            }

            .nav-links.active {
                display: flex;
            }

            .nav-btn {
                width: 100%;
                text-align: left;
                padding: 14px 18px;
                font-size: 1rem;
                border-radius: 12px;
                border-bottom: 1px solid rgba(255,255,255,0.05);
            }

            .mobile-menu-btn {
                display: flex;
            }

            /* === HERO === */
            .hero {
                padding: 80px 0 100px;
            }

            .hero h1 {
                font-size: 2rem;
                line-height: 1.15;
            }

            .hero p {
                font-size: 1rem;
                padding: 0 10px;
            }

            .hero-ctas {
                flex-direction: column;
                padding: 0 16px;
                gap: 12px;
                margin-bottom: 40px;
            }

            .btn {
                width: 100%;
                justify-content: center;
                padding: 14px 20px;
            }

            .hero-stats {
                gap: 30px;
                flex-wrap: wrap;
                justify-content: center;
            }

            .stat-item h3 {
                font-size: 1.5rem;
            }

            /* === DASHBOARD === */
            section[style*="margin-top: -60px"] > div,
            .container > div[style*="justify-content: space-between"] {
                flex-direction: column !important;
                gap: 20px !important;
            }

            /* Dashboard progress row */
            div[style*="flex: 1; min-width: 300px"] {
                min-width: unset !important;
                width: 100% !important;
            }

            /* Dashboard stat buttons */
            div[style*="stat-btn"] {
                flex-wrap: wrap;
            }

            /* Category cards grid → 1-col */
            .grid-7 {
                grid-template-columns: 1fr;
                gap: 16px;
                padding: 40px 0;
            }

            /* Cards on mobile */
            .card {
                padding: 24px 20px;
            }

            .card:hover {
                transform: none;
            }

            /* === PAGE PADDING === */
            .page {
                padding: 40px 0;
            }

            .container {
                padding: 0 16px;
            }

            /* === TOPIC DETAIL / PRACTICE PAGE === */
            div[style*="breadcrumb"],
            #topic-breadcrumb {
                font-size: 0.8rem !important;
                white-space: nowrap;
                overflow: hidden;
                text-overflow: ellipsis;
            }

            /* Practice question tabs */
            .tab-row,
            div[style*="display: flex; gap: 10px"] {
                flex-wrap: wrap;
                gap: 8px;
            }

            /* === CODING SECTION === */
            /* Language switcher buttons row */
            #btn-lang-python, #btn-lang-c, #btn-lang-java {
                padding: 10px 16px !important;
                font-size: 0.85rem !important;
            }

            /* Code card — remove horizontal overflow */
            .code-editor pre {
                font-size: 0.8rem;
                overflow-x: auto;
                -webkit-overflow-scrolling: touch;
            }

            /* Sample test cases grid → 1-col */
            div[style*="grid-template-columns: 1fr 1fr"] {
                grid-template-columns: 1fr !important;
            }

            /* === SCENARIO SECTION === */
            #scenario-problem-container {
                gap: 20px !important;
            }

            /* Scenario problem card */
            #scenario-problem-container .card,
            div[id^="sc-prob-"] {
                padding: 24px 16px !important;
            }

            /* Scenario header — stack on mobile */
            .page div[style*="justify-content: space-between; align-items: flex-end"] {
                flex-direction: column !important;
                align-items: flex-start !important;
                gap: 16px !important;
            }

            /* Scenario timer block */
            div[style*="scenario-session-timer"] {
                width: 100% !important;
            }

            /* Scenario tabs wrap */
            .sc-tab-btn {
                padding: 10px 12px;
                font-size: 0.75rem;
                letter-spacing: 0.5px;
            }

            /* Sample input/output → stacked on mobile */
            div[id^="sc-prob-"] > div[style*="grid-template-columns: 1fr 1fr"],
            .card > div[style*="grid-template-columns: 1fr 1fr"] {
                grid-template-columns: 1fr !important;
                gap: 16px !important;
            }

            /* Scenario code box */
            div[id^="sc-code-box-"] {
                font-size: 0.8rem !important;
                padding: 16px !important;
                overflow-x: auto;
                -webkit-overflow-scrolling: touch;
            }

            /* Problem title on scenario */
            div[id^="sc-prob-"] h3 {
                font-size: 1.3rem !important;
            }

            /* === MOCK TEST === */
            .test-body {
                padding: 16px !important;
            }

            #mock-question-area-inner {
                gap: 10px !important;
            }

            .mock-question-desc {
                max-height: 250px;
                padding: 16px !important;
                border-radius: 8px !important;
            }

            .mock-question-desc h3 {
                font-size: 1.1rem !important;
            }

            .mock-question-desc p {
                font-size: 0.85rem !important;
            }

            .mock-question-editor,
            .compiler-wrapper {
                height: 480px !important;
                border-radius: 8px !important;
            }

            .compiler-header-bar {
                padding: 8px 10px;
                gap: 8px;
            }

            .compiler-file-tab {
                padding: 5px 10px;
                font-size: 0.75rem;
            }

            .icon-btn {
                padding: 4px;
            }

            .icon-btn svg {
                width: 15px;
                height: 15px;
            }

            .btn-compile {
                padding: 6px 12px;
                font-size: 0.8rem;
            }

            .line-numbers-sidebar {
                min-width: 30px;
                padding: 10px 5px;
                font-size: 0.75rem;
            }

            .real-editor,
            .code-highlight-layer {
                font-size: 0.8rem;
                padding: 10px 8px;
            }

            .compiler-console {
                padding: 10px 12px;
                font-size: 0.75rem;
                min-height: 80px;
                max-height: 150px;
            }

            #mock-section-nav {
                padding: 8px 12px !important;
                gap: 4px !important;
                overflow-x: auto;
                -webkit-overflow-scrolling: touch;
                scrollbar-width: none;
            }

            #mock-section-nav::-webkit-scrollbar {
                display: none;
            }

            .mock-nav-btn {
                font-size: 0.75rem !important;
                padding: 6px 10px !important;
                white-space: nowrap;
            }

            #mock-timer {
                font-size: 1rem !important;
            }

            /* Mock test start cards */
            .mock-test-container {
                border-radius: 12px;
            }

            /* === INPUT GUIDE === */
            .input-guide-content .card {
                padding: 20px !important;
            }

            /* Code blocks inside input guide */
            .input-guide-content pre,
            .input-guide-content code {
                font-size: 0.78rem !important;
                overflow-x: auto;
            }

            /* === QUIZ in TOPIC === */
            #quiz-container .test-body {
                padding: 20px !important;
            }

            /* Test options on mobile */
            .test-option {
                padding: 12px 16px;
                font-size: 0.9rem;
            }

            /* === FOOTER === */
            footer {
                padding: 60px 0 30px;
            }

            .footer-content {
                grid-template-columns: 1fr;
                gap: 32px;
            }

            .footer-about p {
                max-width: 100%;
            }

            .footer-bottom {
                padding-top: 24px;
                font-size: 0.8rem;
            }

            /* === GENERAL HEADING SIZES === */
            h2[style*="font-size: 2.8rem"] {
                font-size: 1.8rem !important;
            }

            h2[style*="font-size: 2.2rem"] {
                font-size: 1.6rem !important;
            }

            /* Scrollable horizontal tabs */
            div[style*="display: flex; gap: 15px"][style*="flex-wrap: wrap"] {
                overflow-x: auto;
                flex-wrap: nowrap !important;
                -webkit-overflow-scrolling: touch;
                scrollbar-width: none;
                padding-bottom: 4px;
            }
        }

        /* ---- VERY SMALL PHONES (≤480px) ---- */
        @media (max-width: 480px) {

            .hero {
                padding: 60px 0 80px;
            }

            .hero h1 {
                font-size: 1.7rem;
            }

            .logo {
                font-size: 1.05rem;
            }

            /* Stat items → 3-column compact */
            .hero-stats {
                gap: 20px;
            }

            .stat-item h3 {
                font-size: 1.3rem;
            }

            /* Mock compiler full-width header stacked */
            .mock-question-editor,
            .compiler-wrapper {
                height: 420px !important;
            }

            .compiler-header-bar {
                flex-direction: column;
                align-items: stretch;
            }

            .compiler-header-bar > div {
                justify-content: space-between;
            }

            .compiler-actions {
                width: 100%;
                justify-content: space-between;
            }

            .undo-redo-btns {
                gap: 4px;
            }

            .real-editor,
            .code-highlight-layer {
                font-size: 0.75rem;
                line-height: 1.5;
            }

            .line-numbers-sidebar {
                display: none;
            }

            .card {
                padding: 20px 14px;
            }

            /* Scenario problem card */
            div[id^="sc-prob-"] {
                padding: 18px 12px !important;
            }

            /* Scenario tabs */
            .sc-tab-btn {
                padding: 8px 10px;
                font-size: 0.7rem;
            }

            /* Code box scroll */
            div[id^="sc-code-box-"] {
                font-size: 0.75rem !important;
                padding: 12px !important;
            }

            /* Problem title */
            div[id^="sc-prob-"] h3 {
                font-size: 1.1rem !important;
            }

            /* Coding list cards */
            .code-editor pre {
                font-size: 0.75rem;
            }

            /* Footer single column */
            .footer-content {
                grid-template-columns: 1fr;
            }

            /* Dashboard accuracy text */
            div[id="stat-accuracy-text"] {
                font-size: 2.5rem !important;
            }

            /* Buttons in hero */
            .btn {
                font-size: 0.9rem;
                padding: 12px 16px;
            }
        }

        /* ---- EXTRA SMALL (≤360px) ---- */
        @media (max-width: 360px) {
            .hero h1 {
                font-size: 1.5rem;
            }

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

            .sc-tab-btn {
                padding: 7px 8px;
                font-size: 0.65rem;
                letter-spacing: 0;
            }

            nav {
                height: 56px;
            }

            .logo {
                font-size: 0.95rem;
            }

            .container {
                padding: 0 12px;
            }
        }

        /* ---- TOUCH IMPROVEMENTS ---- */
        @media (hover: none) {
            .card:hover {
                transform: none;
                box-shadow: none;
            }

            .btn:hover {
                transform: none;
            }

            .btn-wa:hover,
            .btn-tg:hover {
                transform: none;
                box-shadow: none;
            }

            /* Better tap targets */
            .nav-btn,
            .sc-tab-btn,
            .mock-nav-btn,
            .test-option {
                min-height: 44px;
            }
        }

        /* ---- SMOOTH SCROLLING ---- */
        html {
            scroll-behavior: smooth;
            -webkit-tap-highlight-color: transparent;
        }

        /* Prevent horizontal scroll on mobile */
        body {
            overflow-x: hidden;
            max-width: 100vw;
        }

        /* Better mobile text input */
        input, textarea, select {
            font-size: 16px; /* prevents iOS zoom on focus */
        }

        /* ---- BOTTOM NAVIGATION BAR for MOBILE ---- */
        .mobile-bottom-nav {
            display: none;
        }

        @media (max-width: 768px) {
            .mobile-bottom-nav {
                display: flex;
                position: fixed;
                bottom: 0;
                left: 0;
                width: 100%;
                background: rgba(10, 15, 30, 0.97);
                backdrop-filter: blur(20px);
                border-top: 1px solid rgba(255,255,255,0.08);
                z-index: 998;
                padding: 6px 0 max(6px, env(safe-area-inset-bottom));
                justify-content: space-around;
            }

            .mobile-bottom-nav-btn {
                display: flex;
                flex-direction: column;
                align-items: center;
                gap: 3px;
                padding: 6px 12px;
                background: none;
                border: none;
                color: var(--muted);
                font-size: 0.6rem;
                font-weight: 700;
                cursor: pointer;
                transition: 0.2s;
                text-transform: uppercase;
                letter-spacing: 0.5px;
                font-family: inherit;
                -webkit-tap-highlight-color: transparent;
                min-width: 52px;
            }

            .mobile-bottom-nav-btn .mob-icon {
                font-size: 1.3rem;
                line-height: 1;
            }

            .mobile-bottom-nav-btn.active {
                color: var(--blue);
            }

            .mobile-bottom-nav-btn.active .mob-icon {
                filter: drop-shadow(0 0 6px rgba(96, 165, 250, 0.6));
            }

            /* Adjust main body to not hide behind bottom nav */
            body {
                padding-bottom: calc(70px + env(safe-area-inset-bottom));
            }

            footer {
                margin-bottom: 0;
            }
        }