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

        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            min-height: 100vh;
            display: flex;
            align-items: center;
            justify-content: center;
            color: white;
        }

        .game-container {
            background: rgba(255, 255, 255, 0.1);
            backdrop-filter: blur(10px);
            border-radius: 20px;
            padding: 30px;
            box-shadow: 0 25px 45px rgba(0, 0, 0, 0.1);
            border: 1px solid rgba(255, 255, 255, 0.2);
            max-width: 500px;
            width: 100%;
        }

        .game-header {
            text-align: center;
            margin-bottom: 30px;
        }

        .game-title {
            font-size: 2.5rem;
            font-weight: 700;
            margin-bottom: 10px;
            text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
            background: linear-gradient(45deg, #ff6b6b, #4ecdc4);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        .game-controls {
            display: flex;
            gap: 10px;
            margin-bottom: 20px;
            flex-wrap: wrap;
            justify-content: center;
        }

        .control-btn {
            padding: 10px 20px;
            border: none;
            border-radius: 25px;
            background: rgba(255, 255, 255, 0.2);
            color: white;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            backdrop-filter: blur(10px);
        }

        .control-btn:hover {
            background: rgba(255, 255, 255, 0.3);
            transform: translateY(-2px);
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
        }

        .control-btn.active {
            background: linear-gradient(45deg, #ff6b6b, #4ecdc4);
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
        }

        .game-board {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 5px;
            margin: 20px auto;
            background: rgba(255, 255, 255, 0.1);
            padding: 10px;
            border-radius: 15px;
            max-width: 300px;
        }

        .cell {
            aspect-ratio: 1;
            background: rgba(255, 255, 255, 0.2);
            border: none;
            border-radius: 10px;
            font-size: 2.5rem;
            font-weight: bold;
            cursor: pointer;
            transition: all 0.3s ease;
            color: white;
            display: flex;
            align-items: center;
            justify-content: center;
            position: relative;
            overflow: hidden;
        }

        .cell:hover:not(.taken) {
            background: rgba(255, 255, 255, 0.3);
            transform: scale(1.05);
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
        }

        .cell.taken {
            cursor: not-allowed;
        }

        .cell.x {
            color: #ff6b6b;
            text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
        }

        .cell.o {
            color: #4ecdc4;
            text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
        }

        .cell.winning {
            animation: winning-glow 1s ease-in-out infinite alternate;
        }

        @keyframes winning-glow {
            0% { 
                background: rgba(255, 255, 255, 0.3);
                box-shadow: 0 0 10px rgba(255, 255, 255, 0.5);
            }
            100% { 
                background: rgba(255, 255, 255, 0.6);
                box-shadow: 0 0 20px rgba(255, 255, 255, 0.8);
            }
        }

        .cell.placed {
            animation: cell-place 0.5s ease-out;
        }

        @keyframes cell-place {
            0% {
                transform: scale(0) rotate(180deg);
                opacity: 0;
            }
            50% {
                transform: scale(1.2) rotate(90deg);
            }
            100% {
                transform: scale(1) rotate(0deg);
                opacity: 1;
            }
        }

        .game-status {
            text-align: center;
            margin: 20px 0;
            font-size: 1.2rem;
            font-weight: 600;
            min-height: 30px;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .stats {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 10px;
            margin-top: 20px;
        }

        .stat-item {
            background: rgba(255, 255, 255, 0.1);
            padding: 15px;
            border-radius: 10px;
            text-align: center;
            backdrop-filter: blur(10px);
        }

        .stat-number {
            font-size: 1.5rem;
            font-weight: bold;
            margin-bottom: 5px;
        }

        .stat-label {
            font-size: 0.9rem;
            opacity: 0.8;
        }

        .difficulty-selector {
            margin: 20px 0;
            text-align: center;
        }

        .difficulty-label {
            display: block;
            margin-bottom: 10px;
            font-weight: 600;
        }

        .difficulty-buttons {
            display: flex;
            gap: 10px;
            justify-content: center;
            flex-wrap: wrap;
        }

        .particle {
            position: absolute;
            width: 4px;
            height: 4px;
            background: white;
            border-radius: 50%;
            pointer-events: none;
            animation: particle-explode 1s ease-out forwards;
        }

        @keyframes particle-explode {
            0% {
                transform: scale(1);
                opacity: 1;
            }
            100% {
                transform: scale(0) translate(var(--dx), var(--dy));
                opacity: 0;
            }
        }

        .game-mode {
            text-align: center;
            margin-bottom: 20px;
        }

        .mode-label {
            display: block;
            margin-bottom: 10px;
            font-weight: 600;
        }

        .thinking {
            opacity: 0.7;
            position: relative;
        }

        .thinking::after {
            content: '';
            position: absolute;
            top: 50%;
            left: 50%;
            width: 20px;
            height: 20px;
            margin: -10px;
            border: 2px solid transparent;
            border-top: 2px solid rgba(255, 255, 255, 0.8);
            border-radius: 50%;
            animation: spin 1s linear infinite;
        }

        @keyframes spin {
            0% { transform: rotate(0deg); }
            100% { transform: rotate(360deg); }
        }

        .reset-btn {
            width: 100%;
            margin-top: 20px;
        }

        @media (max-width: 480px) {
            .game-container {
                padding: 20px;
                margin: 20px;
            }
            
            .game-title {
                font-size: 2rem;
            }
            
            .cell {
                font-size: 2rem;
            }
            
            .control-btn {
                padding: 8px 16px;
                font-size: 0.9rem;
            }
        }