/* 响应式处理：适配小屏设备 */
@media (max-width: 600px) {
    #help-container {
        padding: 20px;
        font-size: 15px;
        width: 300px;
    }
    #help-container h2 {
        font-size: 18px;
    }
    #help-container p {
        font-size: 14px;
    }

    .close-help-button {
        font-size: 15px;
        padding: 10px 20px;
        width: 100%;
    }

    .cell.square {
        width: 30px;
        height: 30px;
    }

    .cell.wall.vertical {
        width: 9px;
        height: 30px;
    }

    .cell.wall.horizontal {
        width: 30px;
        height: 9px;
    }

    .cell.center {
        width: 9px;
        height: 9px;
    }

    .selector {
        padding: 0 3px 3px 3px;
        border-radius: 4px;
        max-height: 60vh;
    }

    .selector .title {
        font-size: 14px;
        padding: 2px 0;
    }

    .selector button {
        width: 28px;
        padding: 1px;
        margin-bottom: 1px;
        font-size: 12px;
    }

    .selector .clear-btn {
        width: 100px;
        margin-top: 5px;
        padding: 1px;
        font-size: 12px;
    }

    .selector .preview {
        width: 27px;
        height: 27px;
    }
    .selector .preview td {
        width: 9px;
        height: 9px;
    }
    .selector .preview .attach {
        width: 9px;
        height: 9px;
    }

    .back-home {
        font-size: 12px;
        padding: 5px 10px;
        top: 8px;
        left: 8px;
    }

    .control-btn {
        width: 35px;
        height: 35px;
        font-size: 20px;
        top: 8px;
    }
    .help-button {
        right: 8px;
    }
    .redo-button {
        right: 48px;
    }
    .undo-button {
        right: 88px;
    }

    /* 按钮仅在移动端显示 */
    .direction-controls {
        display: flex;
    }
}