<style>
.section {
clear: both;
padding: 0px;
margin: 0px;
}
.col {
display: block;
float:left;
margin: 1% 0 1% 1.6%;
}
.col:first-child { margin-left: 0; }
.group:before,
.group:after { content:""; display:table; }
.group:after { clear:both;}
.group { zoom:1; }
.span_2_of_2 {
width: 100%;
}
.span_1_of_2 {
width: 49.2%;
}
@media only screen and (max-width: 480px) {
.col {
margin: 1% 0 1% 0%;
}
}
@media only screen and (max-width: 480px) {
.span_2_of_2, .span_1_of_2 { width: 100%; }
}
</style>
<div class="section group">
<div class="col span_1_of_2">
This is column 1
</div>
<div class="col span_1_of_2">
This is column 2
</div>
</div>