Lesson 1 / 28

What is CSS?

CSS styles HTML — and three ways to attach it to a page.

CSS in one line

CSS (Cascading Style Sheets) describes how HTML elements look — color, spacing, layout, fonts, motion. HTML gives structure; CSS gives appearance.

Three ways to add CSS

Inline (style="..." on a tag), internal (a <style> block in <head>), and external (a separate .css file linked in). External is the standard for real projects.

All three side by side

Same visual result, three attachment points.

<!-- inline -->
<p style="color: crimson;">Inline</p>

<!-- internal -->
<head>
  <style>
    p { color: crimson; }
  </style>
</head>

<!-- external -->
<head>
  <link rel="stylesheet" href="styles.css">
</head>

Prefer external

External stylesheets are cached by the browser and reused across pages — inline styles are the hardest to maintain and override.