why here is a position: relative on os-viewport?

[Reverier-Xu]

Good day! thank you for your excellent work!

I'm writing an announcement page and I want to add a "back to top" button to the bottom left corner of this page. I found that there is a position: relative on the .os-padding.os-viewport class, which prevents me from positioning the button to the bottom left corner of the entire page. I tried unchecking this and found that it did not have bad effect to the layout of the page, and the button positioning works.

I'm wondering if this property is necessary? While I can still use position: fixed to position the button to the bottom left corner, I would prefer to have the button positioned relative to the container, rather than the entire window.

[KingSora]

Good day @Reverier-Xu

Its needed in certain cases like:

• having padding
• using the absolute padding option
• having a browser or os which isn't supporting scrollbar styling