CSS Variables
CSS custom properties, commonly called "CSS variables," are one of the most powerful modern CSS features. They enable dynamic theming, maintainable design systems, and real-time JavaScript integration — things preprocessor variables simply cannot do.
Pseudo Elements and Classes
These are powerful CSS selectors that target elements based on their state, position, or let you inject virtual elements into the page without touching the HTML.
Specificty and Cascade
The cascade is the algorithm CSS uses to resolve conflicts when multiple rules target the same element. Understanding it deeply is the key to writing CSS that works predictably without resorting to !important.
Advanced Custom Properties
Beyond simple variable declarations, CSS custom properties enable powerful runtime theming, component APIs, and JavaScript integration patterns.
Modern CSS Features
This page covers the newest CSS capabilities that are now production-ready. These are the features AI tools generate, modern browsers support, and that will shape how CSS is written going forward.
CSS Debugging Workflow
Debugging CSS is a skill. This guide covers systematic approaches, DevTools mastery, and the specific patterns that resolve the most common CSS bugs — including WordPress-specific issues.
CSS Accessibility (WCAG)
Accessibility is not optional for professional web design service work. It's a legal requirement in many jurisdictions and increasingly demanded by clients. The good news: most CSS accessibility work is a small set of well-understood patterns applied consistently.
CSS Math Functions
CSS math functions let you perform calculations directly in CSS without JavaScript. They are the foundation of modern fluid, responsive design — and AI tools use them constantly. Understanding them means you can validate, correct, and guide AI output with precision.
CSS Values, Keywords, and Inheritance
Understanding what CSS keywords like auto, none, normal, initial, inherit, and unset actually mean prevents hours of debugging. These are the building blocks of every CSS declaration — used constantly but rarely explained in depth.
CSS Logical Properties
Logical properties replace physical direction keywords (left, right, top, bottom) with context-aware equivalents (inline-start, inline-end, block-start, block-end). They are the modern standard for building layouts that work correctly in all languages, including Right-to-Left (RTL) and vertical writing modes.
CSS Nesting
CSS nesting is now a native browser feature — no Sass, no build step required. Write nested rules directly in plain CSS and the browser handles them. This page covers the syntax, specificity behavior, key differences from Sass, and how to guide AI to use nesting correctly.
View Transitions
View Transitions is a modern browser API that lets you animate the change between two states — whether that's navigating between pages, switching tabs in a UI, or any DOM update. It captures a "before" and "after" screenshot of your page and animates between them with CSS.
CSS Shapes and Clipping
CSS gives you powerful tools for creating non-rectangular elements — clipped shapes, text that flows around irregular regions, and complex masking effects. These are among the most visually impressive CSS techniques and appear frequently in premium web design.
Feature Queries (@supports)
@supports lets you apply CSS only if the browser supports a specific property or value. It's the CSS equivalent of JavaScript feature detection — write better CSS for modern browsers while gracefully falling back for older ones.
CSS env() Variables
env() gives you access to environment-defined values set by the browser or operating system — most importantly, the safe area insets that account for device notches, home indicators, and rounded screen corners on modern phones.
@property and Typed Custom Properties
@property (CSS Properties and Values API / CSS Houdini) lets you register CSS custom properties with a defined type, initial value, and inheritance behavior. The most powerful result: you can animate CSS variables — something normally impossible with standard var().