Grids is based on WordPress block editor, which means that you'll be able to use it together with the myriad of content blocks that developers and designers from all around World are creating..
By default, Areas will be the width, which means that, if you've chosen 2- Area layout, each one of them will be covering half of Section width.
When selecting different type of arrangement for Section, the content you had added to your Areas will adapt to the new layout..
Make columns equally tall if this setting is set to ON, all Areas belonging to Section will be forced to have the height if the setting is OFF, the height of each Area will depend on its content..
As for Dimensions settings, the Background settings are dependent on the width you want to target..
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