CSS
Quick Definition
CSS (Cascading Style Sheets) is the language that controls how your WordPress site looks — colors, fonts, spacing, layout, and responsive behavior. Your theme's style.css file contains the CSS rules that define your site's visual design.
What Is CSS?
CSS controls visual presentation. HTML = structure, CSS = appearance. Colors, fonts, spacing, layout, animations, responsive behavior. Every theme has a style.css file.
How CSS Works
h1 { color: #1e293b; font-size: 2.5rem; }
- Selector — Which element to style
- Property — What to change
- Value — How to change it
Cascading = more specific selectors override general ones.
CSS in WordPress
- Theme stylesheet —
style.css, override via child themes - Customizer → Additional CSS — Custom snippets
- Page builders — Elementor/Divi generate CSS visually
- WPCode — Code snippet plugins
Key Concepts
| Concept | What It Does |
|---|---|
| Flexbox | Row/column layout |
| CSS Grid | 2D page layouts |
| Media queries | Responsive design |
| Variables | Reusable values |
| Minification | Reduce file size |
Why It Matters
Understanding basic CSS gives you control beyond the Customizer — fix designs, tweak spacing, change colors without a developer.
Sources: MDN, WPBeginner
Related Terms
MinificationMinification is the process of removing unnecessary characters from CSS, JavaScript, and HTML files — like whitespace, comments, and line breaks — to reduce file sizes and make your WordPress site load faster.Responsive DesignResponsive design is a web design approach that makes your website automatically adapt to any screen size — desktop, tablet, or mobile. It uses CSS media queries and flexible layouts to ensure your WordPress site looks and works great on every device.ThemeA WordPress theme is a collection of files that controls how your website looks — its layout, colors, fonts, and overall design. You can switch themes to completely change your site's appearance without losing any content.
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