This should actually be easy to fix. The widths for the main columns are being set here.
https://blog.likeitwinit.com/wp-content/themes/musicmagazine/style.css (starting at line 374):
#content {
float: left;
width: 560px;
overflow: hidden;
}
#content .mag_posts {
float: left;
width: 270px;
margin: 0 6px 6px 0;
color: #858585;
font: 11px Arial;
}
The .mag_posts are divs that float within the main #content div. They are each 270px wide, which leaves just enough room for them to float two side-by-side. If you want them to float in a single column instead, just change the width of .mag_posts to any value greater than 280px. That will force them to float in a single column, since there won’t be enough room left in the #content div to fit two across.
