feat: add CSS variables (#2913)

Author: MartinCupela

package.json

@@ -235,6 +235,7 @@
     "prettier-fix": "yarn prettier --write",
     "fix-staged": "lint-staged --config .lintstagedrc.fix.json --concurrent 1",
     "start": "tsc --watch --sourceMap --declarationMap",
+    "start:css": "sass --watch src/styling/index.scss dist/css/index.css",
     "prepare": "husky install",
     "preversion": "yarn install",
     "test": "jest",

src/styling/index.scss

@@ -1 +1,2 @@
+@use "./variables.css";
 @import 'modern-normalize' layer(css-reset);