:root {
    --primary-color: #4a6fa5;
    --secondary-color: #6b8cae;
    --accent-color: #ff7e5f;
    --light-color: #f8f9fa;
    --dark-color: #343a40;
    --success-color: #28a745;
    --warning-color: #ffc107;
    --danger-color: #dc3545;
    --border-radius: 8px;
    --box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Poppins', sans-serif;
    background-color: #f5f7fa;
    color: var(--dark-color);
    line-height: 1.6;
    padding: 20px;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    background-color: white;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
}

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

header h1 {
    color: var(--primary-color);
    font-size: 2.5rem;
    margin-bottom: 5px;
}

.subtitle {
    color: var(--secondary-color);
    font-size: 1rem;
}

.game-setup {
    background-color: #f8f9fa;
    padding: 20px;
    border-radius: var(--border-radius);
    margin-bottom: 20px;
}

.player-inputs {
    display: flex;
    gap: 20px;
    margin-bottom: 20px;
    justify-content: center;
}

.input-group {
    flex: 1;
    max-width: 300px;
}

.input-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 600;
    color: var(--primary-color);
}

.input-group input {
    width: 100%;
    padding: 10px;
    border: 2px solid #e9ecef;
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
}

.input-group input:focus {
    border-color: var(--primary-color);
    outline: none;
}

.btn {
    display: inline-block;
    padding: 12px 24px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    text-align: center;
}

.btn:hover {
    background-color: var(--secondary-color);
    transform: translateY(-2px);
}

.btn.secondary {
    background-color: var(--light-color);
    color: var(--dark-color);
    border: 1px solid #dee2e6;
}

.btn.secondary:hover {
    background-color: #e9ecef;
}

.game-status {
    text-align: center;
    margin: 20px 0;
    min-height: 30px;
}

#status-message {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--primary-color);
    padding: 10px;
    background-color: #f8f9fa;
    border-radius: var(--border-radius);
}

.game-board {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    max-width: 400px;
    margin: 0 auto 30px;
}

.cell {
    aspect-ratio: 1/1;
    background-color: white;
    border: 2px solid #e9ecef;
    border-radius: var(--border-radius);
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 3rem;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition);
}

.cell:hover {
    background-color: #f8f9fa;
    transform: scale(1.03);
}

.cell.x {
    color: var(--primary-color);
}

.cell.o {
    color: var(--accent-color);
}

.game-controls {
    text-align: center;
    margin-top: 20px;
}

@media (max-width: 600px) {
    .player-inputs {
        flex-direction: column;
        align-items: center;
    }
    
    .input-group {
        max-width: 100%;
    }
    
    .game-board {
        max-width: 100%;
    }
}