.articles{
width: 350px;
height: 340px;
float: left;
background: url("http://www.ajna.com/archives/images/articles.jpg") no-repeat top left;
margin-top: 10px;
margin-left: 60px;
}

.videos{
width: 350px;
height: 340px;
float: right;
background: url("http://www.ajna.com/archives/images/videos.jpg") no-repeat top center;
margin-top: 64px;
margin-right: 40px;
}