头部栏

<style>
header{ position:fixed; top:0; left:0; right:0; z-index:888; width:100%;}
.pp_nav{ height:49px; background:#6590bd; border-bottom:1px solid #4775a7;display: -webkit-box;display: -moz-box;display: box; width:100%; overflow:hidden; position:relative;}
.pp_nav span{ display:block; text-align:center; color:#fff;}
.pp_nav span:first-child,.pp_nav span:last-child{padding: 0 10px;border: 1px solid #4775a7;height: 28px;margin: 10px 10px;line-height: 26px;font-size: 14px;border-top: 1px solid #86add8;-webkit-box-shadow: 0px 1px 0px #86add8, 0px -1px 0px #4775a7;}
.pp_nav span:nth-child(2){font-size: 20px;-webkit-box-flex: 1;-moz-box-flex: 1;box-flex: 1;width: 100%; line-height:49px;}
.pp_xyy{-webkit-box-shadow: 0px 2px 5px rgba(0,0,0,0.4);-moz-box-shadow: 0px 2px 5px rgba(0,0,0,0.4);box-shadow: 0px 2px 5px rgba(0,0,0,0.4);}
header,nav{display:block;}
.pp_nav span:first-child,.pp_nav span:last-child{-moz-border-radius: 4px;-webkit-border-radius: 4px;border-radius: 4px;}
header,nav{margin:0;padding:0;border:0;font-size:100%;font:inherit;vertical-align:baseline;outline:none;-webkit-box-sizing:border-box;-moz-box-sizing:border-box;box-sizing:border-box}
</style>
<header><nav class="pp_nav pp_xyy" style="border-bottom:0;"><span onclick="history.go(-1)">返回</span><span>Daydream网盘</span><span onclick="window.open('http://zzz.wodemo.com');">首页</span></nav></header>