CSS Intro

Relax. We'll talk through this in plain words — no textbook voice.

What you'll walk away with

Understand CSS's main job

CSS is a styling language that decides how HTML elements appear in the browser. HTML builds structure with <h1>, <p>, <button> and so on. CSS is what brings those elements to life with color, font size, spacing, layout, animation, and mobile-responsive behavior.

In real projects, without CSS a page might have content but no presentation — and that means poor user experience. Once you know CSS, you can make a button look like a real CTA, make a card look professional, and make sure everything still reads cleanly on mobile.

css

/* This CSS rule selects all <p> elements */
p {
  color: red;
  font-size: 16px;
}

You should see

Every <p> paragraph in the HTML document will have red text color and a font size of 16px.

Tip

CSS works on a "select, then style" system. First you pick an element with a selector, then you set its style with property/value pairs.