.bk_jgq{
    background: linear-gradient(180deg, rgb(245 248 250), rgb(228 239 253));
}
.bk_jgq h2{
    font-size: 54px;
}
.bk_jgq p{
    font-size: 17px;
}
.bk_tu{
    background-image: url(https://static.zhihu.com/heifetz/assets/header_bg.0e85282e.png);
    background-position: bottom;
    background-repeat: no-repeat;
    background-size: contain;
    height: 500px;
    margin: 0 auto;
    text-align: center;
    width: 1200px;
}
.bk_jgq img{
    display: block;
    margin: auto;
}

.bk_zs {
    text-align: center;
    padding: 66px;
}
.bk_zs h3 {
    font-size: 52px;
    color: #727cfd;
}

.bk_165{
    margin-top: 32px;
    font-size: 18px;
    font-weight: 700;
}
.bk_li{
    background: white;
    height: 320px;
}
.bk_li img{
    border-radius: .25rem;
}
.bk_de{
    margin: 12px;
}
.col-md-4 {
    margin-bottom: 26px;
}
@media (max-width: 768px) {
.bk_jgq{
    display: none;
}
}