a{
    font-size: 1rem;
    color:#666;
    text-decoration: none;
}
/*小标题*/
dd{
    line-height: 2.5rem;
    font-size: 1.5rem;
    color: white;
}
/*非链接的字体*/
.ddd{
    color:#666;
    font-size: 0.1rem;
}
/*隐藏但是不脱离文档流,占位不显示*/
.dddd{
    /*隐藏且不显示*/
    visibility:hidden;
    color: black;
}


.top{
    position: relative;
}
.top2{
    position: relative;
}
.top3{
    position: relative;
    text-align:center;
}

body{
    display: flex;
    min-height: 100vh;
    flex-direction: column;
}
.main {
     flex: 1;
 }
.box{
    background-color: black;
}

html{
    height: 100%;margin: 0;padding: 0;
}

/*@media(max-width:540px){ dd { font-size:12px; } .ddd{ font-size:12px; } } !*Android常用宽度*!*/
/*@media(max-width:480px){ dd { font-size:12px; } .ddd{ font-size:12px; }}		!*Android常用宽度*!*/
/*@media(max-width:414px){ dd { font-size:12px; } .ddd{ font-size:12px; }}  !*i6Plus,i7Plus宽度*!*/
/*@media(max-width:375px){ dd { font-size:12px; } .ddd{ font-size:12px; }}	!*i6,i7宽度*!*/
/*@media(max-width:360px){ dd { font-size:12px; } .ddd{ font-size:12px; }}	!*Android常用宽度*!*/
/*@media(max-width:320px){ dd { font-size:12px; } .ddd{ font-size:12px; }}*/