<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8">
<style>
.mdf_filter_section{
width:10px;
height:10px;
border:1px solid blue;
display:inline-block;
margin:10px;
}
.mdf_filter_section:first-child {
border:1px solid red;
}
.mdf_filter_section:last-child {
border:1px solid purple;
}
.mdf_filter_section:nth-child(2) {
border:1px solid green;
}
</style>
</head>
<body>
<div class="mdf_filter_section"></div>
<div class="mdf_filter_section"></div>
<div class="mdf_filter_section"></div>
<div class="mdf_filter_section"></div>
</body>
</html>
хм.. хром Версия 39.0.2171.65 m
все ок