<div class="wrap">  <div id="bg">    <div id="title">    <a href="#" class="return">返回</a>    </div>    <a href="#" class="ios">ios下载</a>    <a href="#" class="android">Android下载</a>  </div></div>

body,div,dl,dt,dd,ul,ol,li,h1,h2,h3,h4,h5,h6,pre,code,form,fieldset,legend,input,button,textarea,p,blockquote,th,td,figure {padding:0;margin:0;}fieldset,img{border:0;}:focus {outline:0;}address,caption,cite,code,dfn,em,th,var,optgroup {font-style:normal;font-weight:normal;}h1,h2,h3,h4,h5,h6 {font-size:100%;}abbr,acronym {border:0;font-variant:normal;}input,button,textarea,select,optgroup,option {font-family:inherit;font-size:inherit;font-style:inherit;font-weight:inherit;}code,kbd,samp,tt {font-size:100%;}body {line-height:1.5;}ol,ul,li {list-style:none;}table {border-collapse:collapse;border-spacing:0;}caption,th {text-align:left;}sup,sub {font-size:100%;vertical-align:baseline;}blockquote,q {quotes:none;}blockquote:before,blockquote:after,q:before,q:after {content:‘‘;content:none;}.clear:after{clear: both;content:‘.‘;display: block;visibility:hidden;height:0;}.clear{zoom:1; clear: both;}.hide {display:none;}section,div,img,a{  -webkit-tap-highlight-color:rgba(0,0,0,0);  -webkit-tap-highlight-color:transparent;/* For some Androids */}input{-webkit-appearance:none;}

.wrap{position:relative;}#bg{background:url(../images/bg.jpg) no-repeat center bottom;background-size:100%;}#title{ width:100%; height:7%;}a{ text-indent:-9999px; display:block;}.return{width:16%;height:100%; float:right;}.ios{ width:100%; height:15%; margin-top:93%;}.android{ width:100%; height:15%;}

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