Constrain the Contentbox column widths

If you want to show two columns of Contentbox content constrained to your template width (or even a custom width) you can do this via the Contentbox Settings Popup.

To constrain the Contentbox column widths

Click the BLUE COG icon top left of the active Contentbox section in the editor.
Find and click the SECTION WIDTH section.
Set the dropdown COMBINED BOXES WIDTH to the required value.
The outer section container remains 100% wide. You can set a background colour for this outer section via the BACKGROUND OPTION area.

Combined box width settings

While you can set the width to a specific pixel width, there are some additional settings that can be used - these might not work in older templates.

Default Template Width	Constrains the section columns to the default width as specified in the theme
Default Content Width	Attempts to vertically align the multi-column content with the standard single column content
Fullwidth	Stretches the content full width across the page

Setting a Background Colour for the entire Section

Example of a constrained 2 column section block - the background colour still stretches full width.

By default setting a Background Colour via the GENERAL PROPERTIES > BACKGROUND COLOUR on a two column Section snippet will set the background colour for the active column.

To set a background colour for the entire Section, click the BACKGROUND OPTIONS section button, then set the colour via the OUTER BACKGROUND COLOUR field.

Background Images cannot be applied to the entire Section

At this time there is no option to set a Background Image to the entire Section. Background Images can only be applied to the individual Section Column on multi-column layouts.