Is there any rule for the sizing values used in Bootstrap SCSS?

[MohamadSalman11]

I often see in SCSS files that sizing values such as padding-top: 1.25rem and margin: 0.75rem etc. are commonly used. Should I always follow the rule of using increments of 0.25, or can I use any value like padding: 0.19rem? Is there a resource that explains such guidelines?

[julien-deramond]

I'm not sure if there are explicit rules documented somewhere, but it’s primarily tied to the spacing scale you're using. Common values like 0.25rem, 0.75rem, and 1.25rem are based on a 16px font size base, so, for instance, 0.25 * 16 gives you 4px. If you use something like 0.19rem, that would equal 3.04px, which isn’t ideal because non-integer pixel values can lead to inconsistencies or rounding issues in rendering.
On top of that, the choice between using rem, px, or em can also depend on how you want the layout to behave when users zoom in or out. It depends on the use cases and renderings.