*{margin:0;padding:0;}
html {
    min-width: 320px;
    max-width: 640px;
    margin: 0 auto;
}
body{
    min-width: 320px;
    max-width: 640px;
    margin: 0 auto;
}
.xf{
    min-width: 320px;
    max-width: 640px;
    width:100%;
    height: 100%;
    position:relative;

}
a{ text-decoration: none;color: #fbffff
}
.top{
    min-width: 320px;
    max-width: 640px;
    position: fixed;
    z-index: 100;
}
.top span{
    display: block;
    width: 10%;
}
.top .btn1Box{
    position: absolute;
    top:12%;
    /* right: 21%;*/
    right: 28%;
    cursor: pointer;
}
.top .btn2Box{
    position: absolute;
    top:12%;
    right: 14.5%;
    cursor: pointer;
}
.top .btn3Box{
    position: absolute;
    top:12%;
    right: 1.5%;
    cursor: pointer;
}
.content{font-size: 12px}