What is CSS?
CSS (Cascading Style Sheets) controls how HTML elements look — colors, fonts, sizes, spacing, and layout. This is a foundational concept in styling and visual design that professional developers rely on daily. The explanations below are written to be beginner-friendly while covering the depth and nuance that comes from real-world CSS experience. Take your time with each section and practice the examples
15 min•By Priygop Team•Last updated: Feb 2026
What is CSS?
CSS stands for Cascading Style Sheets. While HTML defines the structure of a page, CSS controls how it looks. Without CSS, every website would look like a plain text document. CSS lets you add colors, change fonts, control spacing, create layouts, and make pages responsive for mobile devices.
What CSS Can Do
- Change text color, size, and font — a critical concept in styling and visual design that you will use frequently in real projects
- Set background colors and images — a critical concept in styling and visual design that you will use frequently in real projects
- Control spacing (margin and padding) — a critical concept in styling and visual design that you will use frequently in real projects
- Create multi-column layouts — a critical concept in styling and visual design that you will use frequently in real projects
- Add animations and transitions — a critical concept in styling and visual design that you will use frequently in real projects
- Make websites responsive (mobile-friendly) — a critical concept in styling and visual design that you will use frequently in real projects
- Style buttons, forms, and navigation menus — a critical concept in styling and visual design that you will use frequently in real projects
Your First CSS
Example
<!DOCTYPE html>
<html>
<head>
<style>
h1 {
color: blue;
font-size: 36px;
}
p {
color: gray;
font-size: 18px;
}
</style>
</head>
<body>
<h1>Hello, CSS!</h1>
<p>CSS makes this text gray and 18px.</p>
</body>
</html>Try It Yourself: Your First CSS
Try It Yourself: Your First CSSCSS
CSS Editor
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