Css in file style

Using @import To Call Your CSS Files | Cascading Style

External CSS Stylesheets - Home and Learn A better place to put all your CSS, however, is in an external file. (By this, we It has just one Class set up, a Pseudo Class for the hover style. Underlines are  Component Styles - Angular

An external style sheet is a separate file with a .css extension with all CSS style definitions for the HTML page(s). You give a reference to this file in the tag 

The styles property takes an array of strings that contain CSS code. Usually you. You can load styles from external CSS files by adding a styleUrls property to a  Style Sheets - Help | PhpStorm - JetBrains

Inline - by using the style attribute in HTML elements; Internal - by using a