.footer {
    position: absolute;
    bottom: 5%;
    left: 0;
    right: 0;
    max-height: 15%;
    min-height: 10%;
}

.footer img {
    width: 70%;
    height: auto;
}

.content_out {
    position: absolute;
    left: 50%; 
    top: 50%;
    transform: translate(-50%, -50%);
    -webkit-transform: translate(-50%, -50%);
    width: 95%;
    height: auto;
    background: url(https://img.foshanplus.com/2020/pic/chan/v2/menu_bak.png) top center no-repeat;
    background-size: 100%;
    opacity: 0.8;
}

.content_out::before {
    content: "";
    padding-top: 100%;
    display: block; 
}

.content {
    position: absolute;
    left: 50%; 
    top: 50%;
    transform: translate(-50%, -50%);
    -webkit-transform: translate(-50%, -50%);
    width: 70%;
}

.content_menu {
    width: 100%;
    display: flex;
}

.mainmenu {
    margin: 1.5vw;
    flex: 1;
    border-radius: 5%;
    cursor: pointer;
}

.mainmenu::before {
    content: "";
    padding-top: 100%;
    display: block; 
}

.m1 {
    background: url(https://img.foshanplus.com/2020/pic/chan/v2/n1.png) top center no-repeat;
    background-size: 100%;
    opacity: 1;
}

.m2 {
    background: url(https://img.foshanplus.com/2020/pic/chan/v2/n2.png) top center no-repeat;
    background-size: 100%;
    opacity: 1;
}

.m3 {
    background: url(https://img.foshanplus.com/2020/pic/chan/v2/n3.png) top center no-repeat;
    background-size: 100%;
    opacity: 1;
}

.m4 {
    background: url(https://img.foshanplus.com/2020/pic/chan/v2/n4.png) top center no-repeat;
    background-size: 100%;
    opacity: 1;
}