Wrap any embed in<iframe> tag, in a parent element, use ratio-16x9 class to set aspect ratio 16:9.

Use ratio-4x3 class to set aspect ratio 4:3.

Use --tb-aspect-ratio: 50% to style element to set aspect ratio 2:1.

Use ratio-21x9 class to set aspect ratio 21:9.

Use ratio-1x1 class to set aspect ratio 1:1.