<div id='preloader'>
<div class='spinner'>
<span class='loader'><span class='loader-inner'></span></span>
</div>
</div>

#preloader{overflow:hidden;background:#fff;left:0;right:0;top:0;bottom:0;position:fixed;z-index:9999}
.spinner{list-style:none;margin:0;padding:0;position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);}
.loader{display:inline-block;width:30px;height:30px;position:relative;border:4px solid #0984e3;top:50%;animation:loader 2s infinite ease}
.loader-inner{vertical-align:top;display:inline-block;width:100%;background-color:#0984e3;animation:loader-inner 2s infinite ease-in}
@keyframes loader{0%{transform:rotate(0deg)}25%{transform:rotate(180deg)}50%{transform:rotate(180deg)}75%{transform:rotate(360deg)}100%{transform:rotate(360deg)}}
@keyframes loader-inner{0%{height:0%}25%{height:0%}50%{height:100%}75%{height:100%}100%{height:0%}}