You my friend, are about to be introduced to the wonderful world of css in conventional apps. ...

Um, no. Whatever issues Gtk3 brought have been fixed and there is nothing for wxPerl/wxWidgets users to do :) #14759 (Unable to set background colour for most controls with gtk3) – wxWidgets

some wxListBox implementations allow setting bg/fg colors/colours , most don't allow setting colours, it depends on the platform ... if you want colors/colour you don't want wxListBox

wxListCtrl allows setting colors/colour on every platform, but you can't customize the headers/headings

wxGrid allows full customization (colour/fonts) of everything headers/items on every platform

I provided these links for OP before, but OP is too tired to type :/
See also wxperl_usage / wxperl-usage / wxPerl::Usage / Class Method Browser , available methods, method invocation syntax, link to docs for some listctrl helpers, they start with "sub Wx::ListCtrl::", and sub Wx::ListCtrl::AddStringItems
Re: wxGridTable how is the grid filled in
Wx::Perl::ListView/Wx::Perl::ListView::SimpleModel
https://metacpan.org/source/MBARBON/Wx-Perl-ListView-0.01/example/listview.pl
Re: Wx::Perl: How to change/set font and size of Wx::ListCtrl column headings?