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

        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            display: flex;
            justify-content: center;
            align-items: center;
            min-height: 100vh;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            padding: 20px;
        }

        .container {
            text-align: center;
        }

        h1 {
            color: white;
            margin-bottom: 30px;
            font-size: 2.5rem;
            text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
        }

        .grid {
            display: grid;
            grid-template-columns: repeat(7, 1fr);
            grid-template-rows: repeat(6, 1fr);
            gap: 12px;
            background-color: #2563eb;
            padding: 25px;
            border-radius: 15px;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
            max-width: 700px;
            margin: 0 auto;
        }

        .cell {
            width: 80px;
            height: 80px;
            background-color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 2rem;
            font-weight: bold;
            transition: all 0.3s ease;
            cursor: pointer;
            box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.1);
        }

        .cell:hover {
            background-color: #fef3c7;
            transform: scale(1.05);
        }

        .cell.x {
            background-color: #ef4444;
            color: white;
        }

        .cell.o {
            background-color: #fbbf24;
            color: white;
        }

        .info {
            color: white;
            margin-top: 20px;
            font-size: 1.2rem;
        }

        .cols {
            display: flex;
            justify-content: center;
            gap: 10px;
            margin: 20px 0;
            flex-wrap: wrap;
        }

        .reset-form {
            margin-top: 15px;
        }

        @media (max-width: 768px) {
            .cell {
                width: 50px;
                height: 50px;
                font-size: 1.5rem;
            }

            h1 {
                font-size: 1.8rem;
            }

            .grid {
                gap: 8px;
                padding: 15px;
            }
        }
        button { 
            width: 100px;
            height: 45px;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            border: none;
            border-radius: 25px;
            cursor: pointer;
            font-weight: bold;
            font-size: 0.9rem;
            margin: 5px;
            transition: all 0.3s ease;
            box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
            text-transform: uppercase;
            letter-spacing: 0.5px;
        }

        button:hover {
            background: linear-gradient(135deg, #5a6fd8 0%, #6a4190 100%);
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(102, 126, 234, 0.6);
        }

        button:active {
            transform: translateY(0);
            box-shadow: 0 2px 10px rgba(102, 126, 234, 0.4);
        }