ul{
    list-style: none;
    padding:0;
    margin:0 auto;
    font-size:12px;
}
a{
    text-decoration: none;
    transition:all .5s ease-in-out;
}
.Nav > ul{
    height:40px;
}
.Nav > ul > li{
    float: left;
    position: relative;
}
.Nav > ul > li > a{
    display: block;
    width:150px;
    height:40px;
    line-height: 40px;
    color:white;
    text-align: center;
    color: #225ba0;
}
.Nav > ul > li:hover > a{
    background-color: #225ba0;
    color: #fff;
}
.Nav > ul > li > ul{
    position:absolute;
    left:0px;
    top:40px;
    color:white;
    text-decoration: none;
    z-index: 100;
}
.Nav > ul > li > ul > li > a{
    display: block;
    text-align: center;
    color:black;
    width:150px;
    height:30px;
    line-height: 30px;
}
.Nav > ul > li > ul > li:nth-child(odd) a{
    background-color: #fff;
}
.Nav > ul > li > ul > li:nth-child(even) a{
    background-color: #fff;
}
.Nav > ul > li:hover > ul > li > a:hover{
    color: #225ba0;
}


/*手风琴*/
.Nav > ul > li > ul{
    height:0px;
    width:0px;
}
.Nav > ul > li > ul > li > a{
    overflow: hidden;
    height:0px;
    transition:all .5s cubic-bezier(0, 0.58, 0.5, 1.7);
}
.Nav > ul > li:hover > ul > li > a{
    height:30px;
}