Incoherent Color Style

[Eolien55]

custom6.css has, for colors :

• Variables, like draculaCyan
• Hard-coded hexadecimal colors, like #6272a4
• Hard-coded rgba colors, like rgba(46,50,66,1)

I think it would be better to replace the hard-coded colors by variables, considering that some are repeted. It would make easier supporting this theme. Hard-coded colors also makes it hard to understand what color exactly is used there.