Knowledge you need
Before continuing, you need to have a basic understanding of the following knowledge:
- HTML /XHTML
Why Use CSS?
- CSS refers to Cascading Style Sheets ( C ascading S tyle S heets)
- Style definitions How to display HTML elements
- Styles are usually stored in style sheets
- Styles were added to HTML 4.0 to solve the issue of separation of content from presentation
- External style sheets can greatly improve work efficiency
- External style sheets are usually stored in CSS files
- Multiple style definitions can cascade into one
Style solves a big problem
HTML tags were originally designed to define document content, as in the following example:
<h1>This is a heading</h1>
<p>This is a paragraph.</p>Style sheets define how HTML elements are displayed, just as font tags and color attributes in HTML play a role. Styles are usually saved in external .css files. We only need to edit a simple CSS document to change the layout and appearance of all pages.