Simple CSS/JS loading screen
HTML
<link rel="stylesheet" href="//maxcdn.bootstrapcdn.com/font-awesome/4.1.0/css/font-awesome.min.css">
<div class="loadingOverlay">
<div class="loadingOverlay-inner">
<span class="fa fa-spinner fa-spin"></span>
<br/>
Daten werden synchronisiert...
</div>
</div>
SCSS
.loadingOverlay {
box-shadow:inset 0 0 20px white;
font-family:sans-serif;
font-weight:lighter;
background:#e3e3e3;
text-align: center;
width:100%;
height:100%;
position:fixed;
top:0;
left:0;
.loadingOverlay-inner {
width:95%;
position:absolute;
top:35%;
text-align: center;
color:#666;
}
.fa {
font-size:40px;
margin-bottom: 20px;
}
}