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If we limit ourselves to the default method of changing backgrouds we will find that any resizing of the input window will not resize the background image (example below);
Notice that when using this method the background image does not resize when the window size is changed (example below);
If a resizing background is required then instead of using the "BACKGROUND IMAGE" button to store our background we should place our image against "CONTENT HEADER TOP" and include some CSS script in the section ".content-header-image" using the "CSS" button.
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