Change the background of a column

To set a custom background for a particular column and component(s) within that column, simply open the edit window for the column you wish to customize.

Under the Background tab, choose a custom background color for your column: 

You can add additional CSS in the CSS tab to further customize this column. For instance, you can make the column white with a border-radius of 15 to make the corners rounded:

Your column and component within that column will now appear with a white background with a border radius of 15 pixels: