* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Arial", sans-serif;
}

body {
    background-color: #f5f5f5;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
}

.container {
    text-align: center;
}

h1 {
    color: #333;
    margin-bottom: 20px;
    font-size: 2.2rem;
}

.game-info {
    margin-bottom: 15px;
    font-size: 1.1rem;
    color: #666;
}

#reset-btn {
    margin-left: 20px;
    padding: 8px 16px;
    border: none;
    background-color: #2c3e50;
    color: white;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
    transition: background-color 0.3s;
}

#reset-btn:hover {
    background-color: #34495e;
}

#chessboard {
    display: grid;
    grid-template-columns: repeat(15, 1fr);
    gap: 1px;
    background-color: #d1b68c;
    padding: 10px;
    border: 10px solid #d1b68c;
    border-radius: 8px;
    box-shadow: 0 0 20px rgba(0,0,0,0.1);
}

.chess-cell {
    width: 30px;
    height: 30px;
    background-color: #e9d8b4;
    cursor: pointer;
    position: relative;
}

/* 响应式：手机端缩小单元格 */
@media (max-width: 600px) {
    .chess-cell {
        width: 22px;
        height: 22px;
    }
    h1 {
        font-size: 1.8rem;
    }
}

.chess-cell.black::after {
    content: "";
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 85%;
    height: 85%;
    border-radius: 50%;
    background-color: #000;
    box-shadow: 0 2px 5px rgba(0,0,0,0.3);
}

.chess-cell.white::after {
    content: "";
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 85%;
    height: 85%;
    border-radius: 50%;
    background-color: #fff;
    box-shadow: 0 2px 5px rgba(0,0,0,0.3);
}

#result {
    margin-top: 20px;
    font-size: 1.3rem;
    color: #e74c3c;
    font-weight: bold;
}