@media (min-width: 769px) {
    
.tu-box{
    display: flex;
    justify-content: flex-start;
    align-items: flex-start ;
    flex-wrap: wrap;
    background-color: #fff;
    padding:5px;
    border-radius: 4px;
    margin-bottom: 40px;
}

}


.tu-item{
    padding:2px;
    /* padding-bottom: 0px !important; */
}

@keyframes tupian
{
    from{background-size: cover;}
    to{background-size: 150% 150% !important;}
}
 
@-webkit-keyframes tupian 
{
    from{background-size: cover;}
    to{background-size: 150% 150% !important;}
}


@keyframes myfirst
{
    from {background-size: 140%;}
    to {background-size: 160%;}
}
 
@-webkit-keyframes myfirst /* Safari 与 Chrome */
{
    from {background-size: 140%;}
    to {background-size: 160%;}
}

div.tu:hover
{
    animation: myfirst 1s;
    -webkit-animation: myfirst 0.5s; /* Safari 与 Chrome */
    animation-fill-mode :forwards ;

}

@media screen and (max-width: 768px) {
.tu-box{
    
    justify-content: flex-start;
    align-items: flex-start ;
    flex-wrap: wrap;
    background-color: #fff;
    padding:5px;
    border-radius: 4px;
    margin-bottom: 40px;
}
}