CSS Best Practices
Writing great CSS isn’t just about knowing properties—it’s about keeping things clean, scalable, and maintainable. Here’s how to do it right in real-world projects.
🔹 1. Naming Conventions (BEM or Utility-Based)
Choose a consistent naming pattern to keep CSS predictable and readable.
✅ BEM (Block Element Modifier)
<div class="card card--featured">
<h2 class="card__title">Title</h2>
</div>
card
: Blockcard__title
: Elementcard--featured
: Modifier
✅ Utility-Based (like Tailwind)
<div class="bg-blue-500 text-white p-4">Hello</div>
Choose one method and stick to it across your project.
🔹 2. CSS Organization
Organize styles into manageable parts:
✅ Folder Structure
/css
├─ base.css
├─ layout.css
├─ components.css
└─ utilities.css
Or if using SCSS:
/scss
├─ _variables.scss
├─ _mixins.scss
├─ _buttons.scss
└─ main.scss
Always keep common, reusable, and utility styles separate.
🔹 3. Performance Optimization
- Minify CSS (use tools like
cssnano
,clean-css
) - Combine multiple files into one
- Remove unused CSS (use PurgeCSS or similar tools)
- Avoid overly complex selectors (e.g.,
ul li a span
) – slow and fragile
🔹 4. Cross-Browser Compatibility
Always check:
- Prefixes with Autoprefixer (
display: -webkit-box;
, etc.) - Use Can I use before using new features
- Test on Chrome, Firefox, Safari, Edge (especially for Flex/Grid)
🔹 5. CSS Reset vs Normalize
CSS Reset | Normalize.css |
---|---|
Removes all default styles | Preserves useful styles |
Often leads to blank slate | Makes browser styles consistent |
Can be harsh | Gentler and safer |
🛠 Use one—not both—based on your preference. Most modern devs prefer Normalize.
🔹 6. Debugging Tools
- 🧪 Use DevTools in Chrome or Firefox
- Enable “Show applied styles” in inspector
- Use
outline: 1px solid red;
for debugging layout - Try browser extensions like:
- VisBug
- CSS Scan
- Web Developer Toolbar
✅ Bonus Tips
- Keep selectors specific but not too deep
- Don’t overuse
!important
- Comment tricky code sections
- Use logical, descriptive names (
.btn-primary
, not.blue-box
) - Write mobile-first CSS where possible
🔚 Summary Covered
- Naming patterns: BEM, Utility
- File structure & modularity
- Optimization & performance tips
- Reset vs Normalize
- Debugging tools & browser checks