* {
    padding: 0;
    margin: 0;
}

.zhishi {
    text-align: center;
    height: auto;
}

.imgP img {
    width: 50%;
    height: 100%;
    float: left;
}
.zhishi h3{
    height: 50px;
    line-height: 50px;
}
.footer{
    background: #f5f5f5;text-align: center;float: left;width: 100%;height: 50px;line-height: 50px;margin-top: 20px
}
.footer span{
    font-size: 15px;
}
.footer a{
    color:#000;text-decoration: none
}