Problem Description:

By default, the archives template has a right sidebar. You may want to remove the sidebar and have 3 columns for the archive thumbnails. This document relates to themes with thumbnail columns in the archives only (Azione, Gigawatt)

Answer:

 

Modifications are your responsibility to maintain! The following is in theory and has not been tested. Always be sure to update your theme to the latest version before editing template files.

 Step 1: Hide the Sidebar

Go to Theme Options and add the following style to the Custom CSS box:

#archives-page #right-column{display: none;}

#archives-page #left-column{width: 100%;}

Click Save Changes

Step 2: Add a 3rd column

Add the following below the other styles

.archives_list li:nth-child(3n+3) {
    margin-right: 0;
}
.archives_list li:nth-child(3n+4) {
    clear: left;
}
.archives_list li:nth-child(2n+2) {
margin-left: 20px;
}
.archives_list li:nth-child(2n+3) {
    clear: none;
}
Click Save Changes