footer{
    width:100%;
    max-width:73rem;
    height : 3.8rem;
}
footer .cy{
    margin-bottom : 1rem;
    text-align : center;
    font-size : 0.6rem;
    color : #c0c5cc;
}
footer .footer_nav{
    width:100%;
    max-width:73rem;
    position: fixed;
    bottom : 0;
    left:50%;
    transform: translateX(-50%);
    display: flex;
    gap: 0;
}
footer .footer_nav a{
    width:50%;
    height : 2.6rem;
    cursor: pointer;
    background-color: #007BFF;
    border: none;
    text-align : center;
}
footer .footer_nav a span{
    text-align : center;
    color : #ffffff;
    display:block;
    margin-top : -0.4rem;
    font-weight : bold;
}
footer .footer_nav .svg{
    width  : 1.5rem;
    height : 1.5rem;
}


/* 下滑动画 */
@keyframes slide_down {
    from { transform: translateY(-100%);}
    to { transform: translateY(0%);}
}
/* 上升动画 */
@keyframes slide_up {
    from { transform: translateY(0%);}
    to { transform: translateY(-100%);}
}
/*遮罩层*/
.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    z-index: 99;
    display : none;
}