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There are many options for defining the background display of a block. You can apply a simple color or background image, as well as manage more layers of background images.
If you set the Background to Background Image, use the following settings to define the background image display:
Background Size: Set this option to determine how the background image is scaled in relation to the width of the block
Background Repeat: Set this to repeat the background image to fill the available space in the
Background Position: Set this option to determine how the background image is anchored in relation to the block:
Background Attachment: Set the attachment type to determine how the background image moves in relation to the scrolling page