CSS Interview Questions

Hey there! This article provides useful information for candidates preparing for CSS interview questions for web developers. The combination of interview questions you can ask the employer and CSS interview question, will provide you with strong guidance.

The guide includes a discussion of both strategic candidate interview questions and situational interview questions.

Also check: CSS roadmap

Let’s dive in.

Beginner Level CSS Interview Questions

1. What is the box model in CSS?
   It defines how elements are sized: content + padding + border + margin.
2. How is margin different from padding?
   Margin adds space outside an element’s border; padding adds space inside the border.
3. Explain Flexbox vs. CSS Grid.
   Flexbox is for 1D layouts (rows or columns). Grid handles 2D layouts (rows and columns).
4. How do you center a div horizontally and vertically?
   Use Flexbox: display: flex; justify-content: center; align-items: center;.
5. What are CSS pseudo-classes? Give an example.
   They style elements in specific states. Example: a:hover changes link color on hover.
6. What’s specificity in CSS?
   Rules determine which styles apply when conflicts arise. Inline styles > IDs > classes > tags.
7. How does position: absolute work?
   It positions an element relative to its nearest positioned ancestor (not static).
8. What is responsive design?
   Designs adapt to screen sizes using media queries, fluid grids, and flexible images.
9. How to hide an element without deleting it?
   Use display: none (removes space) or visibility: hidden (keeps space).
10. Explain em vs. rem units.
    em is relative to parent’s font size. rem is relative to the root (HTML) font size.
11. How to apply a CSS style only to mobile devices?
    Use a media query: @media (max-width: 768px) { ... }.
12. What’s the purpose of z-index?
    It controls stacking order of elements (higher values appear on top).
13. Why use CSS variables?
    They store reusable values (e.g., colors) for easier maintenance.
14. How to optimize CSS for performance?
    Minify code, reduce unused styles, and use transform/opacity for animations.
15. What is BEM methodology?
    A naming convention: Block__Element–Modifier (e.g., .menu__item--active).
16. How to handle browser-specific CSS issues?
    Use vendor prefixes (e.g., -webkit-) or tools like Autoprefixer.
17. When to avoid !important?
    It overrides all styles, making debugging harder. Use sparingly for fixes.
18. What’s the difference between inline and inline-block?
    inline ignores height/width. inline-block allows sizing but stays inline.
19. How to create a CSS-only loading spinner?
    Use @keyframes with border and transform properties for rotation.
20. Why use a CSS preprocessor like Sass?
    Adds features like variables, nesting, and mixins for cleaner, modular code.

Check for CSS interview preparation: CSS Cheat Sheets

Final Thoughts

That’s it! These CSS interview questions will increase your interview performance. The questions serve as preparation for web programming interview questions and can help develop strategic interview questions for candidate assessment.

You will discover that these are among the best interview questions. Keep practicing. Stay curious. May success be yours for your upcoming interview, which deserves rockstar status. You’ve got this! Share feedback if you like.