Search notes:

CSS: @media (… aspect-ratio: )

Change the background color depending of the width to height ratio of the media's viewport:

<style>

 @media (min-aspect-ratio: 3/2) { body { background-color: lightblue ; } } /* Wider than aspect ratio  */
 @media (max-aspect-ratio: 3/2) { body { background-color: lightcoral; } } /* Taller than aspect ratio */

</style>

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