@babel/preset-env is a smart preset that allows you to use the latest JavaScript without needing to micromanage which syntax transforms (and optionally, browser polyfills) are needed by your target environment(s). This both makes your life easier and JavaScript bundles smaller!| babeljs.io
We all have run into CSS collisions and sudden regressions in our codebases when new styles are written or 3rd-party styles are added. This is because of the interdependence of styles due to source order, specificity, and inheritance. Some ways to control the cascade have included methodologies like ITCSS and BEM and other newer native features. Cascade layers will be the ultimate native solution for resolving conflicts between multiple sources of styles. Cascade layers introduce the new at...| Smashing Magazine
This is your complete guide to CSS cascade layers, a CSS feature that allows us to define explicit contained layers of specificity.| CSS-Tricks