#float-btn {
    position: absolute;
    left: 0;
    bottom: 50px; /* 初始高度 */
    width: 40px;
    height: 60px;
    background-color: white;
    color: #333;
    font-size: 24px;
    display: flex;
    justify-content: center;
    align-items: center;
    border-radius: 0 8px 8px 0;
    border-top: 1px solid #000;
    border-bottom: 1px solid #000;
    border-right: 1px solid #000;
    border-left: none; /* 去掉左边框 */
    cursor: pointer;
    z-index: 9;
}

#float-btn .icon-menu {
    width: 12px;
    height: 12px;
    background: url('./img/more_menu.svg') no-repeat center / contain;
}

#float-btn .icon-arrow {
    width: 12px;
    height: 12px;
    background: url('./img/more_arrow.svg') no-repeat center / contain;
}

/* 遮罩层样式 */
.float-mask {
    position: absolute;
    top: 0;
    left: 0; 
    width: 70px; /* 按钮宽度加缓冲区 */
    height: 100%;
    z-index: 999;
    background: transparent;
    touch-action: none;
}