.container {
    text-align: center;
    margin: 20px auto;
    max-width: 600px;
    position: relative;
}

#board {
    background-color: #DEB887;
    margin: 20px auto;
    display: block;
}

.controls {
    margin: 20px;
}

button {
    padding: 10px 20px;
    font-size: 16px;
    cursor: pointer;
    margin: 0 10px;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 4px;
}

button:disabled {
    background-color: #cccccc;
    cursor: not-allowed;
}

.game-info {
    display: flex;
    justify-content: space-around;
    margin: 20px auto;
    padding: 10px;
    background-color: #f5f5f5;
    border-radius: 4px;
}

.status {
    margin: 10px;
    padding: 10px;
    color: #666;
    font-size: 16px;
}

.current-player {
    font-weight: bold;
}

#player {
    color: #4CAF50;
}

.pause-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    color: white;
    font-size: 24px;
    display: none;
}

.mode-select, .difficulty-select {
    margin: 20px 0;
}

.mode-btn, .diff-btn {
    padding: 8px 16px;
    margin: 0 10px;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
}

.mode-btn.active {
    background-color: #2E7D32;
    box-shadow: 0 0 5px rgba(0,0,0,0.3);
}

.diff-btn {
    background-color: #607D8B;
}

.diff-btn.active {
    background-color: #455A64;
    box-shadow: 0 0 5px rgba(0,0,0,0.3);
}

#surrender {
    background-color: #f44336; /* 红色按钮 */
}

#surrender:disabled {
    background-color: #cccccc;
}