In your Vue Project, add your favourite CSS Framework vis npm.

npm install tachyons --save-dev

In main.js add:

import 'tachyons/css/tachyons.min.css' 
// no need for ./../node_modules/ prefix

---

Adding a Static CSS File

Add style.css to /public/:

In /public/index.html reference the Style Sheet:

<link rel="stylesheet" type="text/css" href="style.css">

Standard Underline, Standard Underline, Hamburgefonts

.standard-underline { text-decoration: underline; }

Bottom Border, Bottom Border Over, Hamburgefonts

.bottom-border { border-bottom: 2px solid red; }

Box Shadow, Box Shadow, Hamburgefonts

.box-shadow { box-shadow: inset 0px -3px 0 #72caff; }

Box Shadow, Box Shadow, Hamburgefonts

.box-shadow { padding-bottom: 2px; box-shadow: inset 2px -2px 0 yellow; }

https://www.w3.org/TR/css3-selectors/#attribute-substrings [att*=val] code[class*="language-"] { } <code class="language-c language-js"> Represents an element with the att attribute whose value contains at least one instance of the substring “val”. If “val” is the empty string then the selector does not represent anything.
[att^=val] Represents an element with the att attribute whose value begins with the prefix “val”. If “val” is the empty string then the selector does not represent anything.
[att$=val] Represents an element with the att attribute whose value ends with the suffix “val”. If “val” is the empty string then the selector does not represent anything.