.zhishi_list{
 margin-top: 10px;
 text-align: center;
}
.zhishi_list li{
 display: inline-block;
 margin-right: 10px;
}
.zhishi_list li:last-of-type{
 margin-right: 0;
}
.zhishi_list li img{
 transition: all 0.2s linear;
}
.zhishi_list li img:hover{
 transform: scale(1.01);
}
@media only screen and (max-width: 640px){
 .zhishi_list li{
 float: none;
 width: 100%;
 margin-bottom: 10px;
 }
 .zhishi_list li img{
 width: 100%;
 }
}