Idea Summary
Column freeze and header freeze option needed for classic report

Use Case
In a dashboard where there are multiple regions and real estate is of premium, cannot use IR as it take lot of space and performance is not as good as classic.

Preferred Solution (Optional)
Currently I am using css to achieve this, but freezing of column requires background color to be opaque, The below variables I am using for old and even rows, but they are transparent.

--ut-report-cell-alt-background-color
--ut-report-cell-background-color)

I will be happy, if two additional variables can be provided having same color with zero transparency.

This requirement is so generic that , I feel Freeze col & header for classic should come out of box.

Also , I would like Apex to provide a way in designer/developer tool to set customized UI properties for the elements like modifying the padding/border etc, where typically every application developer does something or the other in css.