.demo_tab ul {
    display: flex;
    align-items: center;
    justify-content: space-around;
}

.demo_tab ul {
    flex: 1;
    text-align: center;
    height: .55rem;

}
.sanjiao{
    width: 0px;
    height: 0px;
    border: 0.05rem solid transparent;
    border-top-color: #153a87;
    position: absolute;
    bottom: -0.1rem;
    left: 50%;
    animation: op 1s linear;
    display: none;
    transform: translate(-50%);
}
.demo_tab ul li {
    /*width: 25%;*/
    flex: 1;
    position: relative;
    display: inline-block;
    height: .55rem;
    line-height: .55rem;
    border: 1px solid #E4E4E4;
    font-size: .2rem;
    font-family: Microsoft YaHei;
    font-weight: 400;
    color: #000000;
    border-left: none;
}

.demo_tab ul li:nth-child(1) {
    border-left: 1px solid #E4E4E4;
}

.pic_box img{
    width: 3.9rem;
    transition: all 0.6s;
    height: 2.6rem;
}
.content_box{
    margin: .35rem 0 .95rem 0;
}
.tab_item{
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    /* animation: op 1.5s ; */
}
.pic_box {
    overflow: hidden;
    width: 3.9rem;
    height: 2.6rem;
    margin-bottom: .2rem;
}
.pic_box img:hover{
    transform: scale(1.2); 
}
.activeMenu1{
    animation: op 1s linear;
    background-color: #153a87;
    color: #fff !important; 
    height: 0.57rem !important;
}
@keyframes op {
    0%{
        opacity: 0;
    }
    100%{
        opacity: 1;
    }
}