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

        :root {
            --primary-neon: #00ffff;
            --secondary-neon: #ff00ff;
            --success-green: #00ff88;
            --error-red: #ff0055;
            --dark-bg: #0a0a0f;
            --card-bg: #1a1a2e;
            --text-color: #ffffff;
            --shadow-glow: 0 0 20px rgba(0, 255, 255, 0.5);
        }

        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            background: linear-gradient(135deg, #0a0a0f 0%, #1a1a2e 50%, #16213e 100%);
            color: var(--text-color);
            min-height: 100vh;
            display: flex;
            justify-content: center;
            align-items: center;
            padding: 20px;
            position: relative;
            overflow-x: hidden;
        }

        /* Animated Background Particles */
        .bg-animation {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            pointer-events: none;
            z-index: 0;
            overflow: hidden;
        }

        .particle {
            position: absolute;
            background: var(--primary-neon);
            border-radius: 50%;
            opacity: 0.3;
            animation: float 8s infinite ease-in-out;
        }

        @keyframes float {
            0%, 100% {
                transform: translateY(0) translateX(0);
            }
            50% {
                transform: translateY(-30px) translateX(30px);
            }
        }

        /* Main Container */
        .container {
            max-width: 900px;
            width: 100%;
            background: rgba(26, 26, 46, 0.9);
            border-radius: 20px;
            padding: 40px;
            box-shadow: 0 0 40px rgba(0, 255, 255, 0.3),
                        0 0 80px rgba(255, 0, 255, 0.2);
            backdrop-filter: blur(10px);
            border: 2px solid rgba(0, 255, 255, 0.3);
            position: relative;
            z-index: 1;
            animation: slideUp 0.6s ease-out;
        }

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

        /* Title with Typing Animation */
        .title {
            text-align: center;
            font-size: 2.5rem;
            font-weight: bold;
            margin-bottom: 30px;
            background: linear-gradient(90deg, var(--primary-neon), var(--secondary-neon));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            text-shadow: 0 0 20px rgba(0, 255, 255, 0.5);
            position: relative;
            overflow: hidden;
        }

        .title::after {
            content: '';
            position: absolute;
            bottom: -10px;
            left: 50%;
            transform: translateX(-50%);
            width: 100px;
            height: 3px;
            background: linear-gradient(90deg, var(--primary-neon), var(--secondary-neon));
            box-shadow: var(--shadow-glow);
            animation: expandLine 0.8s ease-out;
        }

        @keyframes expandLine {
            from {
                width: 0;
            }
            to {
                width: 100px;
            }
        }

        /* Difficulty Selector */
        .difficulty-selector {
            display: flex;
            justify-content: center;
            gap: 15px;
            margin-bottom: 25px;
            flex-wrap: wrap;
        }

        .difficulty-btn {
            padding: 10px 25px;
            border: 2px solid var(--primary-neon);
            background: transparent;
            color: var(--text-color);
            border-radius: 25px;
            cursor: pointer;
            font-size: 0.95rem;
            font-weight: 600;
            transition: all 0.3s ease;
            position: relative;
            overflow: hidden;
        }

        .difficulty-btn::before {
            content: '';
            position: absolute;
            top: 50%;
            left: 50%;
            width: 0;
            height: 0;
            border-radius: 50%;
            background: var(--primary-neon);
            transition: width 0.4s, height 0.4s, top 0.4s, left 0.4s;
            transform: translate(-50%, -50%);
            z-index: -1;
        }

        .difficulty-btn:hover::before {
            width: 300px;
            height: 300px;
        }

        .difficulty-btn:hover {
            color: var(--dark-bg);
            box-shadow: 0 0 20px var(--primary-neon);
        }

        .difficulty-btn.active {
            background: var(--primary-neon);
            color: var(--dark-bg);
            box-shadow: 0 0 20px var(--primary-neon);
        }

        /* Stats Bar */
        .stats-bar {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
            gap: 20px;
            margin-bottom: 30px;
        }

        .stat-item {
            background: rgba(0, 255, 255, 0.1);
            padding: 15px;
            border-radius: 15px;
            border: 2px solid rgba(0, 255, 255, 0.3);
            text-align: center;
            transition: all 0.3s ease;
        }

        .stat-item:hover {
            transform: translateY(-5px);
            box-shadow: 0 5px 20px rgba(0, 255, 255, 0.4);
        }

        .stat-label {
            font-size: 0.85rem;
            color: rgba(255, 255, 255, 0.7);
            margin-bottom: 5px;
            text-transform: uppercase;
            letter-spacing: 1px;
        }

        .stat-value {
            font-size: 1.8rem;
            font-weight: bold;
            background: linear-gradient(90deg, var(--primary-neon), var(--secondary-neon));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        /* Progress Bar */
        .progress-container {
            width: 100%;
            height: 8px;
            background: rgba(255, 255, 255, 0.1);
            border-radius: 10px;
            margin-bottom: 30px;
            overflow: hidden;
            position: relative;
        }

        .progress-bar {
            height: 100%;
            width: 0%;
            background: linear-gradient(90deg, var(--primary-neon), var(--secondary-neon));
            border-radius: 10px;
            transition: width 0.2s ease;
            box-shadow: 0 0 15px var(--primary-neon);
            position: relative;
        }

        .progress-bar::after {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
            animation: shimmer 2s infinite;
        }

        @keyframes shimmer {
            0% {
                transform: translateX(-100%);
            }
            100% {
                transform: translateX(100%);
            }
        }

        /* Sentence Display */
        .sentence-display {
            background: rgba(0, 0, 0, 0.3);
            padding: 25px;
            border-radius: 15px;
            font-size: 1.4rem;
            line-height: 1.8;
            margin-bottom: 25px;
            border: 2px solid rgba(0, 255, 255, 0.2);
            min-height: 100px;
            letter-spacing: 1px;
            font-family: 'Courier New', monospace;
            box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.5);
        }

        .sentence-display span {
            transition: all 0.1s ease;
        }

        .sentence-display span.correct {
            color: var(--success-green);
            text-shadow: 0 0 8px var(--success-green);
        }

        .sentence-display span.incorrect {
            color: var(--error-red);
            background: rgba(255, 0, 85, 0.2);
            text-shadow: 0 0 8px var(--error-red);
        }

        .sentence-display span.current {
            background: rgba(0, 255, 255, 0.3);
            border-bottom: 3px solid var(--primary-neon);
            animation: blink 1s infinite;
        }

        @keyframes blink {
            0%, 50%, 100% {
                opacity: 1;
            }
            25%, 75% {
                opacity: 0.5;
            }
        }

        /* Typing Input */
        .typing-input {
            width: 100%;
            padding: 20px;
            font-size: 1.2rem;
            border: 3px solid var(--primary-neon);
            border-radius: 15px;
            background: rgba(0, 0, 0, 0.5);
            color: var(--text-color);
            resize: none;
            outline: none;
            font-family: 'Courier New', monospace;
            transition: all 0.3s ease;
            box-shadow: 0 0 20px rgba(0, 255, 255, 0.3);
            letter-spacing: 1px;
        }

        .typing-input:focus {
            box-shadow: 0 0 30px rgba(0, 255, 255, 0.6);
            border-color: var(--secondary-neon);
        }

        .typing-input:disabled {
            opacity: 0.5;
            cursor: not-allowed;
        }

        /* Results Section */
        .results-section {
            margin-top: 30px;
            padding: 30px;
            background: linear-gradient(135deg, rgba(0, 255, 255, 0.1), rgba(255, 0, 255, 0.1));
            border-radius: 15px;
            border: 2px solid var(--primary-neon);
            display: none;
            animation: fadeIn 0.5s ease-out;
        }

        @keyframes fadeIn {
            from {
                opacity: 0;
                transform: scale(0.9);
            }
            to {
                opacity: 1;
                transform: scale(1);
            }
        }

        .results-section.show {
            display: block;
        }

        .results-title {
            font-size: 1.8rem;
            text-align: center;
            margin-bottom: 20px;
            color: var(--success-green);
            text-shadow: 0 0 15px var(--success-green);
        }

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

        .result-item {
            text-align: center;
            padding: 15px;
            background: rgba(0, 0, 0, 0.3);
            border-radius: 10px;
            border: 1px solid rgba(255, 255, 255, 0.2);
        }

        .result-label {
            font-size: 0.9rem;
            color: rgba(255, 255, 255, 0.7);
            margin-bottom: 8px;
        }

        .result-value {
            font-size: 2rem;
            font-weight: bold;
            background: linear-gradient(90deg, var(--primary-neon), var(--secondary-neon));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        /* Restart Button */
        .restart-btn {
            width: 100%;
            padding: 15px;
            font-size: 1.1rem;
            font-weight: bold;
            border: none;
            border-radius: 12px;
            background: linear-gradient(90deg, var(--primary-neon), var(--secondary-neon));
            color: var(--dark-bg);
            cursor: pointer;
            transition: all 0.3s ease;
            box-shadow: 0 5px 20px rgba(0, 255, 255, 0.4);
            text-transform: uppercase;
            letter-spacing: 2px;
            margin-top: 20px;
        }

        .restart-btn:hover {
            transform: translateY(-3px);
            box-shadow: 0 8px 30px rgba(0, 255, 255, 0.6);
        }

        .restart-btn:active {
            transform: translateY(0);
        }

        /* Leaderboard */
        .leaderboard {
            margin-top: 30px;
            padding: 25px;
            background: rgba(0, 0, 0, 0.3);
            border-radius: 15px;
            border: 2px solid rgba(255, 0, 255, 0.3);
        }

        .leaderboard-title {
            font-size: 1.5rem;
            text-align: center;
            margin-bottom: 20px;
            color: var(--secondary-neon);
            text-shadow: 0 0 15px var(--secondary-neon);
        }

        .leaderboard-list {
            list-style: none;
        }

        .leaderboard-item {
            display: flex;
            justify-content: space-between;
            padding: 12px;
            margin-bottom: 10px;
            background: rgba(255, 255, 255, 0.05);
            border-radius: 8px;
            border-left: 4px solid var(--primary-neon);
            transition: all 0.3s ease;
        }

        .leaderboard-item:hover {
            background: rgba(255, 255, 255, 0.1);
            transform: translateX(5px);
        }

        .leaderboard-rank {
            font-weight: bold;
            color: var(--secondary-neon);
        }

        .leaderboard-score {
            color: var(--primary-neon);
        }

        /* Theme Toggle */
        .theme-toggle {
            position: absolute;
            top: 20px;
            right: 20px;
            width: 60px;
            height: 30px;
            background: rgba(255, 255, 255, 0.1);
            border-radius: 30px;
            cursor: pointer;
            border: 2px solid var(--primary-neon);
            padding: 3px;
            transition: all 0.3s ease;
        }

        .theme-toggle-ball {
            width: 22px;
            height: 22px;
            background: var(--primary-neon);
            border-radius: 50%;
            transition: all 0.3s ease;
            box-shadow: 0 0 10px var(--primary-neon);
        }

        /* Light Mode */
        body.light-mode {
            background: linear-gradient(135deg, #f0f0f0 0%, #e0e0e0 50%, #d0d0d0 100%);
        }

        body.light-mode .container {
            background: rgba(255, 255, 255, 0.9);
            color: #333;
        }

        body.light-mode .title,
        body.light-mode .stat-value,
        body.light-mode .result-value {
            -webkit-text-fill-color: unset;
            color: #333;
        }

        body.light-mode .typing-input,
        body.light-mode .sentence-display {
            background: rgba(0, 0, 0, 0.05);
            color: #333;
        }

        body.light-mode .theme-toggle-ball {
            transform: translateX(30px);
        }

        /* Responsive Design */
        @media (max-width: 768px) {
            .container {
                padding: 25px;
            }

            .title {
                font-size: 1.8rem;
            }

            .sentence-display {
                font-size: 1.1rem;
                padding: 20px;
            }

            .typing-input {
                font-size: 1rem;
                padding: 15px;
            }

            .stat-value {
                font-size: 1.4rem;
            }

            .result-value {
                font-size: 1.5rem;
            }

            .difficulty-selector {
                gap: 10px;
            }

            .difficulty-btn {
                padding: 8px 20px;
                font-size: 0.85rem;
            }
        }

        @media (max-width: 480px) {
            .container {
                padding: 20px;
            }

            .title {
                font-size: 1.5rem;
            }

            .sentence-display {
                font-size: 1rem;
                padding: 15px;
            }

            .stats-bar {
                grid-template-columns: 1fr;
                gap: 15px;
            }

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

        /* Hidden Class */
        .hidden {
            display: none !important;
        }