Ionic 4 every component implementation and their styles are self-contained, in fact, native shadow-dom is used, so trully isolation in enforced.
However, in Ionic Apps there are global CSS (linked in <head>
) that needs to be included in order for an Ionic app to properly work.
Some of this "global CSS" style html
, normalizes,and configures the typography (font-family, font-size) of the whole page, so apps look like native.