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

        body {
            font-family: "Inter", sans-serif;
            background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
            min-height: 100vh;
            display: flex;
            align-items: center;
            justify-content: center;
            padding: 20px;
            color: #f8fafc;
        }

        .game-container {
            width: 100%;
            max-width: 800px;
            position: relative;
        }

        .screen {
            display: none;
            animation: fadeIn 0.5s ease-in;
        }

        .screen.active {
            display: block;
        }

        /* Welcome Screen Styles */
        .welcome-card {
            background: rgba(15, 23, 42, 0.8);
            backdrop-filter: blur(20px);
            border: 1px solid rgba(100, 116, 139, 0.3);
            border-radius: 20px;
            padding: 40px;
            text-align: center;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
        }

        .welcome-header {
            margin-bottom: 40px;
        }

        .icon-container {
            width: 80px;
            height: 80px;
            background: linear-gradient(135deg, #dc2626, #b91c1c);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 20px;
            animation: pulse 2s infinite;
            box-shadow: 0 5px 15px rgba(220, 38, 38, 0.3);
        }

        .icon-container i {
            font-size: 32px;
            color: white;
        }

        .game-title {
            font-size: 3rem;
            font-weight: 700;
            background: linear-gradient(135deg, #3b82f6, #1d4ed8);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            margin-bottom: 10px;
            text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
        }

        .game-subtitle {
            font-size: 1.2rem;
            color: #cbd5e1;
            margin-bottom: 20px;
        }

        .stats-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 20px;
            margin-bottom: 40px;
        }

        .stat-card {
            background: rgba(30, 41, 59, 0.7);
            border: 1px solid rgba(100, 116, 139, 0.2);
            border-radius: 15px;
            padding: 20px;
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 10px;
            transition: transform 0.3s ease;
        }

        .stat-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 5px 15px rgba(220, 38, 38, 0.2);
        }

        .stat-card i {
            font-size: 24px;
            color: #ef4444;
        }

        .stat-label {
            font-size: 0.9rem;
            color: #94a3b8;
        }

        .stat-value {
            font-size: 1.8rem;
            font-weight: 700;
            color: #3b82f6;
        }

        .button-container {
            display: flex;
            flex-direction: column;
            gap: 15px;
        }

        .primary-btn {
            background: linear-gradient(135deg, #dc2626, #b91c1c);
            color: white;
            border: none;
            padding: 20px 40px;
            border-radius: 15px;
            font-size: 1.2rem;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 10px;
            box-shadow: 0 5px 15px rgba(220, 38, 38, 0.3);
        }

        .primary-btn:hover {
            transform: scale(1.05);
            box-shadow: 0 10px 30px rgba(220, 38, 38, 0.4);
        }

        .secondary-btn {
            background: transparent;
            color: #cbd5e1;
            border: 1px solid rgba(100, 116, 139, 0.3);
            padding: 15px 30px;
            border-radius: 10px;
            font-size: 1rem;
            cursor: pointer;
            transition: all 0.3s ease;
        }

        .secondary-btn:hover {
            background: rgba(30, 41, 59, 0.5);
            color: #3b82f6;
            border-color: #3b82f6;
        }

        /* Game Screen Styles */
        .game-card {
            background: rgba(15, 23, 42, 0.8);
            backdrop-filter: blur(20px);
            border: 1px solid rgba(100, 116, 139, 0.3);
            border-radius: 20px;
            padding: 30px;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
        }

        .game-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 20px;
            flex-wrap: wrap;
            gap: 15px;
        }

        .badges {
            display: flex;
            gap: 10px;
            flex-wrap: wrap;
        }

        .badge {
            padding: 8px 16px;
            border-radius: 20px;
            font-size: 0.9rem;
            font-weight: 500;
        }

        .level-badge {
            background: rgba(59, 130, 246, 0.2);
            color: #93c5fd;
            border: 1px solid rgba(59, 130, 246, 0.3);
        }

        .category-badge {
            background: rgba(220, 38, 38, 0.2);
            color: #fca5a5;
            border: 1px solid rgba(220, 38, 38, 0.3);
        }

        .difficulty-badge.easy {
            background: rgba(34, 197, 94, 0.2);
            color: #86efac;
            border: 1px solid rgba(34, 197, 94, 0.3);
        }

        .difficulty-badge.medium {
            background: rgba(251, 191, 36, 0.2);
            color: #fde047;
            border: 1px solid rgba(251, 191, 36, 0.3);
        }

        .difficulty-badge.hard {
            background: rgba(239, 68, 68, 0.2);
            color: #fca5a5;
            border: 1px solid rgba(239, 68, 68, 0.3);
        }

        .score-section {
            display: flex;
            gap: 20px;
        }

        .score-item {
            text-align: right;
        }

        .score-label {
            display: block;
            font-size: 0.9rem;
            color: #94a3b8;
        }

        .score-value {
            display: block;
            font-size: 1.5rem;
            font-weight: 700;
            color: #3b82f6;
        }

        .progress-section {
            margin-bottom: 30px;
        }

        .progress-bar {
            width: 100%;
            height: 8px;
            background: rgba(30, 41, 59, 0.7);
            border-radius: 4px;
            overflow: hidden;
            margin-bottom: 10px;
        }

        .progress-fill {
            height: 100%;
            background: linear-gradient(90deg, #dc2626, #3b82f6);
            border-radius: 4px;
            transition: width 0.5s ease;
            width: 0%;
        }

        .progress-text {
            text-align: center;
            font-size: 0.9rem;
            color: #94a3b8;
        }

        .question-section {
            text-align: center;
            margin-bottom: 30px;
        }

        .question-text {
            font-size: 1.8rem;
            font-weight: 600;
            margin-bottom: 15px;
            line-height: 1.4;
            color: #f8fafc;
        }

        .points-text {
            font-size: 1.1rem;
            color: #3b82f6;
            font-weight: 500;
        }

        .answer-section {
            display: flex;
            flex-direction: column;
            gap: 15px;
            margin-bottom: 30px;
        }

        #answerInput {
            padding: 20px;
            border: 1px solid rgba(100, 116, 139, 0.3);
            border-radius: 15px;
            background: rgba(30, 41, 59, 0.7);
            color: white;
            font-size: 1.2rem;
            text-align: center;
            outline: none;
            transition: all 0.3s ease;
        }

        #answerInput:focus {
            border-color: #3b82f6;
            box-shadow: 0 0 20px rgba(59, 130, 246, 0.3);
        }

        #answerInput::placeholder {
            color: #64748b;
        }

        .submit-btn {
            background: linear-gradient(135deg, #dc2626, #3b82f6);
            color: white;
            border: none;
            padding: 20px;
            border-radius: 15px;
            font-size: 1.2rem;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            box-shadow: 0 5px 15px rgba(59, 130, 246, 0.3);
        }

        .submit-btn:hover:not(:disabled) {
            transform: scale(1.02);
            box-shadow: 0 10px 30px rgba(59, 130, 246, 0.4);
        }

        .submit-btn:disabled {
            opacity: 0.5;
            cursor: not-allowed;
        }

        .result-section {
            text-align: center;
            animation: slideUp 0.5s ease;
        }

        .result-emoji {
            font-size: 4rem;
            margin-bottom: 20px;
            animation: bounce 1s ease;
        }

        .result-title {
            font-size: 2rem;
            font-weight: 700;
            margin-bottom: 15px;
        }

        .result-title.correct {
            color: #22c55e;
        }

        .result-title.incorrect {
            color: #ef4444;
        }

        .correct-answer {
            font-size: 1.2rem;
            margin-bottom: 20px;
            color: #cbd5e1;
        }

        .correct-answer span {
            color: #3b82f6;
            font-family: "Courier New", monospace;
            font-weight: 700;
            background: rgba(30, 41, 59, 0.7);
            padding: 4px 8px;
            border-radius: 6px;
            border: 1px solid rgba(100, 116, 139, 0.3);
        }

        .explanation {
            background: rgba(30, 41, 59, 0.7);
            padding: 20px;
            border-radius: 15px;
            margin-bottom: 20px;
            animation: fadeIn 0.5s ease;
            border: 1px solid rgba(100, 116, 139, 0.2);
        }

        .explanation p {
            color: #cbd5e1;
            line-height: 1.6;
        }

        .next-btn {
            background: linear-gradient(135deg, #dc2626, #3b82f6);
            color: white;
            border: none;
            padding: 20px 40px;
            border-radius: 15px;
            font-size: 1.2rem;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            box-shadow: 0 5px 15px rgba(220, 38, 38, 0.3);
        }

        .next-btn:hover {
            transform: scale(1.05);
            box-shadow: 0 10px 30px rgba(220, 38, 38, 0.4);
        }

        .back-section {
            text-align: center;
            margin-top: 20px;
        }

        .back-btn {
            background: transparent;
            color: #94a3b8;
            border: none;
            padding: 10px 20px;
            border-radius: 10px;
            cursor: pointer;
            transition: all 0.3s ease;
        }

        .back-btn:hover {
            color: #3b82f6;
            background: rgba(30, 41, 59, 0.5);
        }

        /* Animations */
        @keyframes fadeIn {
            from {
                opacity: 0;
                transform: translateY(20px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        @keyframes slideUp {
            from {
                opacity: 0;
                transform: translateY(30px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        @keyframes bounce {
            0%,
            20%,
            50%,
            80%,
            100% {
                transform: translateY(0);
            }
            40% {
                transform: translateY(-10px);
            }
            60% {
                transform: translateY(-5px);
            }
        }

        @keyframes pulse {
            0% {
                transform: scale(1);
                box-shadow: 0 5px 15px rgba(220, 38, 38, 0.3);
            }
            50% {
                transform: scale(1.05);
                box-shadow: 0 5px 20px rgba(220, 38, 38, 0.5);
            }
            100% {
                transform: scale(1);
                box-shadow: 0 5px 15px rgba(220, 38, 38, 0.3);
            }
        }

        /* Responsive Design */
        @media (max-width: 768px) {
            .game-title {
                font-size: 2rem;
            }

            .question-text {
                font-size: 1.4rem;
            }

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

            .score-section {
                justify-content: center;
            }

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

        @media (max-width: 480px) {
            body {
                padding: 10px;
            }

            .welcome-card,
            .game-card {
                padding: 20px;
            }

            .game-title {
                font-size: 1.8rem;
            }

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