I'm not good at making a cutie alterspring as you say, but I do think accessibility when it comes to theming is important. You should use this to help with checking color contrast.
(Worst theme haver of the site) It is always good to give a peek to colour theory... It does wonders to make even the worst theme look cute... And useing soft colour give it a beam... But most importantly its always better to make it readable to not kill anyone in the process...
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