@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+Devanagari:wght@100..900&display=swap');

        /* ========== RESET & GLOBAL ========== */
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: "Noto Sans Devanagari", sans-serif;
            background: radial-gradient(circle at 10% 30%, #0f172a, #020617);
            min-height: 100vh;
            color: #eef2ff;
            line-height: 1.5;
            /* padding: 1rem; */
        }

        .container-quiz {
            max-width: 1000px;
            margin: 0 auto;
            padding: 0.75rem;
            margin-bottom: 4rem;
        }

        /* ========== 3D BOX SHADOW & BORDER EFFECTS ========== */
        .set-card,
        .quiz-card,
        .result-card {
            background: rgba(255, 255, 255, 0.08);
            backdrop-filter: blur(12px);
            border-radius: .8rem;
            border: 1px solid rgba(139, 92, 246, 0.4);
            box-shadow: 0 25px 45px -12px rgba(0, 0, 0, 0.5), 0 4px 12px rgba(0, 0, 0, 0.2), inset 0 1px 0 rgba(255, 255, 255, 0.1);
            transition: all 0.35s cubic-bezier(0.2, 0.9, 0.4, 1.1);

        }

        .set-card:hover {
            transform: translateY(-8px) scale(1.01);
            box-shadow: 0 35px 50px -18px rgba(0, 0, 0, 0.6), 0 0 0 2px rgba(99, 102, 241, 0.5);
            border-color: #c084fc;
        }

        .quiz-card {
            background: rgba(15, 23, 42, 0.8);
            backdrop-filter: blur(16px);
            padding: 1.8rem 2rem;
            margin: 1.5rem auto;
            max-width: 800px;
        }

        .quiz-card:hover {
            box-shadow: 0 28px 48px -12px rgba(0, 0, 0, 0.6), inset 0 0 0 1px rgba(255, 255, 255, 0.15);
            border-color: #a78bfa;
        }

        /* ========== 3D BUTTON STYLES ========== */
        .set-card button,
        .back-btn,
        .nav-btn,
        .option {
            transition: all 0.12s linear;
            box-shadow: 0 6px 0 rgba(0, 0, 0, 0.25);
            border: none;
            cursor: pointer;
            font-weight: 500;
        }

        .set-card button:active,
        .back-btn:active,
        .nav-btn:active,
        .option:active {
            transform: translateY(3px);
            box-shadow: 0 2px 0 rgba(0, 0, 0, 0.25);
        }

        /* primary 3D gradient button */
        .set-card button,
        .nav-btn.next {
            background: linear-gradient(120deg, #4f46e5, #c026d3);
            color: white;
            border-radius: .8rem;
            font-size: 1.1rem;
            padding: 0.9rem 1.5rem;
            box-shadow: 0 10px 0 -2px #2e1065, 0 8px 20px rgba(0, 0, 0, 0.3);
            letter-spacing: 0.5px;
        }

        .set-card button:active,
        .nav-btn.next:active {
            transform: translateY(5px);
            box-shadow: 0 4px 0 -1px #2e1065;
        }

        .back-btn {
            background: #1e293b;
            color: #cbd5e1;
            width: 48px;
            height: 48px;
            border-radius: 24px;
            font-size: 1.4rem;
            box-shadow: 0 5px 0 #0f172a;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .nav-btn:first-child {
            background: #334155;
            color: #f1f5f9;
            border-radius: 24px;
            box-shadow: 0 5px 0 #1e293b;
            padding: 0.8rem 2rem;
        }

        /* 3D option buttons */
        .option {
            background: rgba(30, 41, 59, 0.95);
            border: 1px solid #475569;
            border-radius: .8rem;
            padding: 1rem 1.5rem;
            color: #f1f5f9;
            font-weight: 500;
            backdrop-filter: blur(4px);
            box-shadow: 0 5px 0 #0f172a;
            width: 100%;
            text-align: left;
            font-size: 1rem;
            transition: all 0.2s;
        }

        .option:hover:not(:disabled) {
            transform: translateY(-2px);
            background: #4f46e5cc;
            border-color: #a78bfa;
            box-shadow: 0 8px 0 #2e1065;
        }

        .option.correct {
            background: #15803dcc;
            border-color: #4ade80;
            box-shadow: 0 5px 0 #14532d;
            color: white;
        }

        .option.wrong {
            background: #b91c1ccc;
            border-color: #f87171;
            box-shadow: 0 5px 0 #7f1a1a;
            text-decoration: line-through;
        }

        .option:disabled {
            cursor: default;
            opacity: 0.9;
        }

        /* ========== TIMER 3D CIRCLE ========== */
        .timer-container-quiz {
            background: radial-gradient(circle at 30% 20%, #1e293b, #0f172a);
            width: 50px;
            height: 50px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            border: 3px solid #c084fc;
            box-shadow: 0 12px 25px rgba(0, 0, 0, 0.5), inset 0 1px 2px rgba(255, 255, 255, 0.2);
            font-weight: 500;
            font-size: 1.3rem;
            color: #facc15;
            transition: 0.2s;
        }

        .timer-container-quiz.low {
            border-color: #ef4444;
            color: #ffb3b3;
            animation: pulseWarning 0.9s infinite;
            box-shadow: 0 0 12px #ef4444;
        }

        @keyframes pulseWarning {
            0% {
                transform: scale(1);
                border-color: #ef4444;
            }

            70% {
                transform: scale(1.08);
                border-color: #ff8c8c;
            }

            100% {
                transform: scale(1);
                border-color: #ef4444;
            }
        }

        /* ========== PROGRESS BAR 3D ========== */
        .progress-container-quiz {
            background: #1e293b;
            border-radius: 24px;
            height: 12px;
            box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.5), 0 1px 0 rgba(255, 255, 255, 0.1);
            margin: 1.5rem 0 1.2rem;
        }

        .progress-bar {
            background: linear-gradient(95deg, #c084fc, #6366f1, #f472b6);
            border-radius: 24px;
            width: 0%;
            height: 100%;
            box-shadow: 0 0 8px #a855f7;
            transition: width 0.4s cubic-bezier(0.2, 0.9, 0.4, 1.1);
        }

        /* ========== HEADER & TYPOGRAPHY ========== */
        .header h1 {
            font-size: 1.8rem;
            background: linear-gradient(135deg, #f0f9ff, #d9f99d, #fbcfe8);
            -webkit-background-clip: text;
            background-clip: text;
            color: transparent;
            text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
            letter-spacing: -0.5px;
        }

        .header {
            text-align: center;
            margin: 4px auto;
        }

        .question-text {
            font-size: 1.3rem;
            font-weight: 400;
            color: #f1f5f9;
            text-shadow: 0 2px 5px rgba(0, 0, 0, 0.3);
            margin-bottom: 1.5rem;
            line-height: 1.4;
        }

        /* ========== EXPLANATION BOX 3D ========== */
        .explanation-box {
            background: linear-gradient(145deg, #0f172ae6, #020617e6);
            border-left: 6px solid #4ade80;
            padding: 1.3rem;
            border-radius: .8rem;
            margin: 1.7rem 0;
            backdrop-filter: blur(12px);
            box-shadow: 0 12px 20px -8px black;
            text-align: justify;
        }

        /* ========== SET GRID ========== */
        .set-screen {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
            gap: 2rem;
            margin-top: 1rem;
        }

        .set-card {
            padding: 1.8rem;
        }

        .set-card .set-number {
            color: #a78bfa;
            font-weight: 500;
            font-size: 1rem;
            margin-bottom: 0.5rem;
        }

        .set-card h3 {
            font-size: 1.25rem;
            margin: 0.5rem 0 1rem;
            color: #e2e8f0;
        }

        /* ========== QUIZ HEADER ========== */
        .quiz-header {
            display: flex;
            align-items: center;
            gap: 1rem;
            flex-wrap: wrap;
        }

        .quiz-info {
            flex: 1;
        }

        .set-name {
            font-size: 1.2rem;
            font-weight: 600;
            background: linear-gradient(130deg, #c084fc, #f0abfc);
            background-clip: text;
            -webkit-background-clip: text;
            color: transparent;
        }

        .question-count {
            background: #4f46e5;
            padding: 0.4rem 1rem;
            border-radius: 10px;
            font-size: 0.85rem;
            font-weight: 500;
            display: inline-block;
            margin-top: 6px;
            box-shadow: inset 0 -1px 0 #2e1065, 0 2px 6px black;
        }

        /* ========== NAVIGATION ========== */
        .navigation {
            display: flex;
            justify-content: space-between;
            gap: 1rem;
            margin-top: 1.8rem;
        }

        .nav-btn {
            display: inline-flex;
            align-items: center;
            gap: 10px;
            font-size: 1rem;
            border-radius: .8rem;
        }

        /* ========== RESULT SCREEN ========== */
        .result-screen {
            background: rgba(0, 0, 0, 0.55);
            backdrop-filter: blur(24px);
            border-radius: 1rem;
            padding: 2.5rem 2rem;
            text-align: center;
            border: 1px solid rgba(167, 139, 250, 0.5);
            animation: fadeInUp 0.6s;
        }

        .score {
            font-size: 4.5rem;
            font-weight: 600;
            background: linear-gradient(145deg, #facc15, #f97316);
            -webkit-background-clip: text;
            background-clip: text;
            color: transparent;
            margin: 1rem 0;
        }

        .restart-btn {
            background: linear-gradient(120deg, #4f46e5, #c026d3);
            border: none;
            padding: 1rem 2rem;
            border-radius: 1rem;
            font-weight: bold;
            font-size: 1.1rem;
            color: white;
            cursor: pointer;
            box-shadow: 0 8px 0 #2e1065;
            transition: 0.08s linear;
            margin-top: 1rem;
        }

        .restart-btn:active {
            transform: translateY(4px);
            box-shadow: 0 4px 0 #2e1065;
        }

        /* ========== ANIMATIONS ========== */
        @keyframes fadeInUp {
            from {
                opacity: 0;
                transform: translateY(40px);
            }

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

        .quiz-card,
        .set-card,
        .result-screen {
            animation: fadeInUp 0.5s ease-out;
        }

        /* ========== RESPONSIVE DESIGN (MOBILE & TABLET) ========== */
        @media (max-width: 768px) {
            .container-quiz {
                padding: 0.5rem;
            }

            .quiz-card {
                padding: 1.2rem;
            }

            .question-text {
                font-size: 1.2rem;
            }

            .option {
                padding: 0.8rem 1.2rem;
                font-size: 0.9rem;
            }

            .timer-container-quiz {
                width: 55px;
                height: 55px;
                font-size: 1.3rem;
            }

            .header h1 {
                font-size: 1.9rem;
            }

            .nav-btn {
                padding: 0.6rem 1.2rem;
                font-size: 0.9rem;
            }

            .set-card h3 {
                font-size: 1.1rem;
            }
        }

        @media (max-width: 520px) {
            .quiz-header {
                flex-wrap: wrap;
                justify-content: space-between;
            }

            .quiz-info {
                width: 100%;
                order: 2;
                margin-top: 10px;
                text-align: center;
            }

            .timer-container-quiz {
                order: 1;
            }

            .back-btn {
                order: 0;
            }

            .option {
                font-size: 0.85rem;
                padding: 0.7rem 1rem;
            }

            .set-card button {
                font-size: 1rem;
                padding: 0.7rem;
            }

            .navigation {
                flex-direction: column;
                gap: 0.8rem;
            }

            .nav-btn {
                justify-content: center;
            }

            .score {
                font-size: 3rem;
            }
        }

        @media (min-width: 769px) and (max-width: 1024px) {
            .question-text {
                font-size: 1.35rem;
            }

            .option {
                font-size: 1rem;
                padding: 1rem 1.3rem;
            }

            .set-screen {
                gap: 1.5rem;
            }
        }

        .hidden {
            display: none !important;
        }

        .options-container-quiz {
            display: flex;
            flex-direction: column;
            gap: 0.9rem;
        }

        i,
        .fas {
            pointer-events: none;
        }



        /* ========== MUSIC PLAYER 3D STYLES ========== */
        .music-player {
            position: fixed;
            bottom: 20px;
            right: 20px;
            z-index: 1000;
            background: rgba(15, 23, 42, 0.85);
            backdrop-filter: blur(12px);
            border-radius: 24px;
            padding: 8px 16px 8px 12px;
            display: flex;
            align-items: center;
            gap: 12px;
            border: 1px solid rgba(139, 92, 246, 0.5);
            box-shadow: 0 10px 25px rgba(0, 0, 0, 0.3), 0 0 0 1px rgba(255, 255, 255, 0.05);
            transition: all 0.3s ease;
        }

        .music-player:hover {
            transform: translateY(-3px);
            border-color: #c084fc;
            box-shadow: 0 15px 30px rgba(0, 0, 0, 0.4);
        }

        .music-btn {
            background: linear-gradient(135deg, #4f46e5, #c026d3);
            border: none;
            width: 42px;
            height: 42px;
            border-radius: 50%;
            color: white;
            font-size: 1.2rem;
            cursor: pointer;
            box-shadow: 0 5px 0 #2e1065;
            transition: all 0.08s linear;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .music-btn:active {
            transform: translateY(3px);
            box-shadow: 0 2px 0 #2e1065;
        }

        .music-info {
            display: flex;
            flex-direction: column;
            font-size: 0.7rem;
            color: #cbd5e1;
        }

        .music-info span:first-child {
            font-weight: 600;
            color: #facc15;
            font-size: 0.75rem;
        }

        .volume-slider {
            width: 80px;
            height: 4px;
            -webkit-appearance: none;
            background: #334155;
            border-radius: 10px;
            outline: none;
            cursor: pointer;
        }

        .volume-slider::-webkit-slider-thumb {
            -webkit-appearance: none;
            width: 12px;
            height: 12px;
            background: #c084fc;
            border-radius: 50%;
            cursor: pointer;
            box-shadow: 0 0 5px #a855f7;
        }

        @media (max-width: 550px) {
            .music-player {
                bottom: 12px;
                right: 12px;
                padding: 5px 12px 5px 8px;
            }

            .music-btn {
                width: 36px;
                height: 36px;
                font-size: 1rem;
            }

            .volume-slider {
                width: 60px;
            }

            .music-info {
                display: none;
            }
        }