CSS Docs

CSS (Cascading Style Sheets) is a style sheet language used to describe the presentation of HTML documents.

Creator: Håkon Wium Lie Profile
W3C Spec Repo

Core Concepts

What is CSS

Style sheet language for designing web content.

History of CSS

Introduced in 1996 to separate structure and style.

Ways to Add CSS

Inline, Internal, and External methods.

CSS Syntax

Selectors, properties, values and how rules are formed.

Selectors & Properties

Selectors

Target elements using tag, class, ID, attribute, etc.

Colors & Units

Hex, RGB, HSL, rem, em, %, px, etc.

Typography

Fonts, sizes, weights, spacing & text decoration.

Box Model

Content, padding, border, and margin areas.

Positioning

static, relative, absolute, fixed, sticky.

Display & Visibility

block, inline, flex, grid, none.

Layout & Visual Design

Flexbox

One-dimensional layout control.

CSS Grid

Two-dimensional layout system.

Spacing & Sizing

margin, padding, width, height, etc.

Borders & Shadows

Style elements with borders, radius, box-shadow.

Backgrounds

Colors, images, gradients, and their properties.

Advanced CSS

Transitions

Animate CSS property changes over time.

Transforms

Rotate, scale, skew, translate elements.

Animations

Keyframes and advanced UI motion.

Media Queries

Responsive designs for various screen sizes.

Custom Properties (Variables)

Reusable values using `--var` syntax.

Best Practices

Organizing, resetting, and maintaining CSS.