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     background-image:url(https://images.cnblogs.com/cnblogs_com/blogs/695483/galleries/2003325/o_210721164919San%20Francisco.jpg); 
     background-repeat: no-repeat; 
     background-attachment: fixed; 
     background-position: center 0; 
     background-size: cover; 
    padding-top:0px;
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#bd {
    display: block;
    background-color: yellow;
    font-size: 200px;
}
#hv {
    display: none;
}
#bd:hover{
    display: block;
    background-color: red;
    font-size: 200px;
}
input {
    border-radius: 15%;
    color: gray;
}
#ad_t2,#cnblogs_c1,#under_post_news,#cnblogs_c2,#under_post_kb,#under_post_card1,#under_post_card2 {
    display:none; !important
}
#live2dcanvas {
    border: 0 !important;
}