different theming approach

[dskvr]

going to refactor themes, as is they work, and are fine, but different approach enables hybrid premade themes with tweaks and customizations completely at runtime, without any prebuild step.

leverage css vars

• https://www.sitepoint.com/theming-tailwind-css-variables-clean-architecture/
• (better) https://svelte.dev/repl/8123d474edb04f198c3b83363716a709?version=4.2.15