Investigate whether components should use CSS variables instead of SCSS

[viktorrusakov]

Using CSS variables might enable runtime theming instead of buildtime which is currently the case. After implementing style dictionary in #1543 we will be able to generate CSS variables from design tokens

AC

• determine if using CSS variables will allow runtime theming in MFEs (possibly create a PoC and demonstrate to @adamstankiewicz)
• if runtime theming is possible with CSS variables determine what it would take for Paragon to switch to CSS variables (carefully consider effect on consumers here), document it and present to @adamstankiewicz (or better to Paragon Working Group!)