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83. How to create a box with fixed Aspect Ratio in CSS?

One way to create a box with fixed aspect ratio in CSS is by using the 'padding-top' property. We can set the padding-top value to a percentage that calculates the element's aspect ratio. For example, if we want to maintain a 16:9 aspect ratio, we can set the padding-top value to 56.25% (calculated by dividing 9 by 16 and then multiplying by 100), and then set the width to 100%. This will create a box that has a fixed aspect ratio of 16:9, and resizes proportionally when the window size changes.

Another solution is to use the 'width' and 'height' properties with a viewport unit, such as 'vh' or 'vw'. For example, we can set the width to a percentage value and height to a viewport height value (e.g. 50vh) to maintain a fixed aspect ratio.

Overall, there are several ways to maintain a fixed aspect ratio using CSS, and the best approach will depend on the specific use case and design requirements.