.body {
    background: url(../images/back.jpg);
    font-family: 'Roboto Slab', serif;
    height: auto;
    vertical-align: top;
    display: flex;
    /*所有子元素样式*/
    align-items: center;
    justify-content: center;
}

.body_B {
    /*边框 border-style: solid;
            border-color: rgb(255, 255, 255);            
            border-width: 1px; 
            margin: 0 auto; 自己水平居中*/
    width: 96%;
    max-width: 998px;
    text-align: center;
    background-color: rgb(24, 24, 24);
    /*背景颜色*/
}

.body_C {
    font-style: normal;
    /*字格式*/
    font-weight: 400;
    /*字粗细*/
    font-size: 14pt;
    color: cornsilk;
    margin-bottom: 15px;
}

.div_DH {
    background-color: rgb(22, 41, 19);
    /*背景颜色*/
    display: flex;
    /*所有子元素样式*/
    align-items: center;
    justify-content: right;
}

.div_W1 {
    background-color: rgb(22, 41, 19);
    /*背景颜色*/
    
    /*display: flex;所有子元素样式align-items: center;justify-content: center;*/
    
    
    /*flex-wrap: wrap;
    实现超出换行
    word-wrap: break-word;
    所有子元素自动换行
    word-break: break-all;
    所有子元素自动换行
    */
}

.biankuang {
    border-style: solid;
    border-color: rgb(25, 25, 25);
    border-width: 1px;
    width: 100%;
    max-width: 497px;
}

ul,
li {
    margin: 0;
    padding: 0;
}

.ulbox {
    width: 998px;
    height: 40px;
}

.ulbox .li {
    list-style: none;
    float: right;
    width: 100px;
    max-height: 40px;
    background: orange;
    text-align: center;
    line-height: 40px;
    overflow: hidden;
    transition: max-height 0.5s;
}

/*这里设置最大高度，就不会有溢出，然后就可以看到*/
.ulbox .li:hover {
    max-height: 200px;
}

/*控制小尖尖的显示*/
.ulbox .li:hover .abox::before {
    display: block;
}

.dropdown {
    width: 100px;
}

.dropdown li {
    list-style-type: none;
    background: rgb(164, 165, 153);
}

.abox {
    position: relative;
    display: block;
    width: 100%;
    height: 100%;
    text-decoration: none;
    font-size: 25pt;
    color: rgb(68, 68, 67);
}

.abox::before {
    content: "";
    border: 10px solid;
    border-color: transparent transparent rgb(164, 165, 153) transparent;
    bottom: 0;
    left: 50%;
    margin-left: -10px;
    display: none;
    position: absolute;
}