I am struggling to create a simple square background image with a navbar that adjusts responsively on different screen sizes. While I have been able to get the image and navbar set up, the image is not expanding the way I want it to. I envision the image fitting from top to bottom on a phone, with the sides running off. As the screen size increases, the image slowly moves into its full shape, and finally, at desktop size, it is centered with a black background filling out the remaining space. I would greatly appreciate any help to achieve this effect.
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