More control over text colors

unless using custom css, it was not possible to use custom Decoration Color on one type of typo _(for example, if one wanted to color only bold text, but not italic, it was not possible)_ this PR aims to let people granularly choose their colors, with the option not to edit the color of a type highlights still defaults to yellow colors but that's by design, wouldn't make sense to allow people to input blank colors for highlighting