How to Add a Hyperlink to External CSS. Cascading style sheets (CSS) are browser instructions for styling HTML elements that can be added to Web pages in one of three ways: externally, internally ...

CSS, or Cascading Style Sheets, defines the look and formatting of that HTML. Both are essential to coding your own website, and here's how to get acquainted with them.

On your website, add buttons that reveal more content when they are clicked. But avoid overwhelming users – a long, text-heavy drop-down of text can feel like a novel.