This is my code for CSS Column
<div id="a">
<div class="b"></div>
<div class="b" style="height:30px;"></div>
<div class="b" style="height:30px;"></div>
<div class="b"></div>
<div class="b"></div>
<div class="b"></div>
</div>
<style>
#a {
position: relative;
display: block;
background:yellow;
width:500px;
}
.b {
background:pink;
width: 40%;
display: inline-block;
height:50px;
vertical-align: top;
margin:10px;
}
</style>