Resolved Use an image as background - Indigo template

Hi,
first you have to enable Boxed-layout (!) in Template Options.
But it would be outside content area, not inside.
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If you want to add background image for example for Bottom template area - it's possible from Template Options > Layout Builder > Bottom > Row Options
https://www.youtube.com/watch?v=8Bj5ojPmKtQ

BUT
If you want to have background image inside Page (SP Page Builder) set Background image inside Row Options > Style