.title_head{
    font-size: 24px;
    border-bottom: 1px solid #e54918;
    line-height: 40px;
}
.free_content{
    width: 850px;
    margin-top: 20px;
}
.class_block{
    width: 262px;
    height: 313px;
    margin-left: 15px;
    float: left;
    border: 1px solid #757575;
    margin-top: 28px;
}
.class_title{
    width: 262px;
    height: 50px;
    line-height: 42px;
    float: left;
    text-align: center;
    color: #515559;
    font-size: 24px;
}
.class_intro{
    width: 232px;
    margin-left: 15px;
    color: #515559;
    height: 115px;
    float: left;
    font-size: 12px;
    line-height: 18px;
}