You can use css to align the button to the bottom of the page:
for example:
position: absolute; bottom: 5%; left: 5%;
You can either enter this in the style property of the button or add a class to the button and put it in the css stylesheets of your application.
Maybe adding an extra Layout Grid is a solution.
Place the first two Layout Grids in the first row and the button ‘Close page’ in the second row.
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| [Layout Grid 1]
| [Layout Grid 2]
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| [Close Page]
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