What is a cascade layer?

Cascade layers are the latest addition to CSS. They allow developers to control the specificity and the source order across multiple CSS files. As a result, developers can minimize CSS collisions and avoid unexpected style changes in their applications.

@layer base{
  @layer theme, components
}

@layer base{
  ...
}

@layer base.theme{
  ...
}

@layer base.components{
  ...
}
refer: https://css-tricks.com/css-cascade-layers/