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🎨Beginner10 lessons · 3 free

CSS Fundamentals

CSS is the formatting layer of the web. If HTML is the document, CSS is the formatting panel — font, size, color, spacing, bold, alignment. This course teaches CSS through hands-on examples, starting with text and colors and building up to responsive layouts that look great on any device.

Prerequisite: HTML Fundamentals
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$59one-time · lifetime access

What you'll learn

What CSS is — the Word formatting toolbar analogy
Selectors — targeting elements by type, class, ID
Colors and typography — font, size, weight, spacing
The box model — content, padding, border, margin
Flexbox — row and column layouts, centering
CSS Grid — two-dimensional page layouts
Responsive design — mobile-first media queries
CSS variables — brand colors, one change updates all
Transitions — smooth hover and focus effects
Build a complete responsive landing page

Course outline

Full course — $59 one-time

04

The Box Model — Every Element Is a Box

The concept that explains how spacing works in CSS — padding, border, margin

7 min
05

Flexbox — Aligning Things in Rows and Columns

The layout system that replaced float hacks — centering and distributing elements

8 min
06

CSS Grid — Building Page Layouts

Two-dimensional layouts — rows AND columns — for full page structures

7 min
07

Responsive Design — Looking Good on Every Screen

The same HTML, different CSS — media queries make layouts adapt to screen size

7 min
08

CSS Variables — Reusable Values

Define your brand colors and spacing once — change them everywhere at once

5 min
09

Transitions — Smooth Hover Effects

Make state changes feel polished instead of instant — with one line of CSS

5 min
10

Build a Landing Page with HTML + CSS

Put everything together — nav, hero, features, CTA, footer, fully responsive

12 min

Get the full course

10 lessons — selectors, box model, flexbox, grid, responsive, variables, transitions, and a complete landing page.

✓ 10 lessons + 4 diagrams✓ Build a landing page✓ Certificate
$59one-time

Written by the RadarTrek editorial team · Reviewed June 2026

About this course

CSS — Cascading Style Sheets — is the language that controls how web pages look. Without CSS, every website would be plain black text on a white background. CSS handles colors, fonts, spacing, layout, animations, and responsive design — making pages look polished on everything from a phone to a large monitor. This CSS tutorial for beginners assumes you know basic HTML and takes you through the styling fundamentals that every front-end developer and web designer uses daily.

Modern CSS — Flexbox and CSS Grid in particular — has transformed what is possible with pure styling, and understanding layout is the skill that separates developers who can implement any design from those who struggle with anything beyond a simple column. After this course you will be writing responsive layouts confidently, understanding the cascade and specificity, and able to recreate any design you see in the browser.

Frequently asked questions

Is CSS hard to learn?

CSS has a reputation for being surprisingly tricky — not because the syntax is complex, but because small changes can have unexpected cascade effects. Understanding the box model, specificity, and how Flexbox and Grid work eliminates most of that frustration. This course builds those mental models correctly from the start, so the pieces click rather than fight each other. Most students feel comfortable with everyday CSS within 2–3 weeks.

Do I need to know HTML before learning CSS?

Yes — CSS styles HTML elements, so understanding HTML structure is a prerequisite. You need to know what a div, span, heading, and paragraph are before you can meaningfully style them. If you have not completed the HTML Fundamentals course yet, start there. The two courses together take a few weeks and give you the complete foundation for writing and designing web pages.

What is the difference between Flexbox and CSS Grid?

Flexbox is a one-dimensional layout system — it arranges items in a row or a column. Grid is two-dimensional — it arranges items in rows AND columns simultaneously. Flexbox is ideal for navigation bars, button groups, and card rows. Grid is ideal for full-page layouts and complex two-axis arrangements. Modern developers use both, often nesting Flexbox inside Grid areas. This course covers both in depth.

Should I learn CSS or Tailwind CSS first?

Learn CSS first, then Tailwind. Tailwind is a utility-class framework built on CSS concepts — if you do not understand what margin, padding, flex, and display mean, Tailwind classes are meaningless strings. Once you understand the underlying CSS properties, Tailwind becomes dramatically faster to write because you already know what each utility does. The CSS Fundamentals course and Tailwind CSS course make an excellent pairing.

What is responsive design and how do I learn it?

Responsive design means building websites that adapt their layout to different screen sizes — phones, tablets, laptops, and wide monitors. The core technique is CSS media queries, which apply different styles at different viewport widths. Modern Flexbox and Grid make responsive layouts much easier than the old float-based approach. This course covers responsive design with real examples so you graduate building pages that work on every device.

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