[4.0] Color selector boxes too small

[PhilETaylor]

Steps to reproduce the issue

safari on Mac

Edit atum template style in Joomla admin
Colour Settings tab

Expected result

I think the color selector boxes should be full height of the input area - or maybe a bootstrap prepend area?

"Choose your hue value for the dark template colour" on one line

Actual result

Choose your hue value for the 
dark template colour

System information (as much as possible)

safari on Mac

[Quy]

PR #30585