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Stack of books. Because you want more than one.

“SMACSS is becoming one of the most useful contributions to front-end discussions in years” *

I’ve been analyzing my process (and the process of those around me) and figuring out how best to structure code for projects on a larger scale. What I've found is a process that works equally well for sites small and large.

Learn how to structure your CSS to allow for flexibility and maintainability as your project and your team grows.

What is it?

SMACSS (pronounced “smacks”) is more style guide than rigid framework. There is no library within here for you to download or install. There is no git repository for you to clone. SMACSS is a way to examine your design process and as a way to fit those rigid frameworks into a flexible thought process. It is an attempt to document a consistent approach to site development when using CSS. And really, who isn’t building a site with CSS these days?!

Get to know Scalable and Modular Architecture for CSS:

Read it Online

SMACSS started out as a free online book and that continues to be true. You can always read the book online.

Download the Book

The e-book comes in PDF, ePub, and mobi formats for easy installation on almost any e-reader. Download the zip!

Download the book!

What's in SMACSS?


  1. About the Author
  2. Introduction


  1. Categorizing CSS Rules
  2. Base Rules
  3. Layout Rules
  4. Module Rules
  5. State Rules
  6. Theme Rules
  7. Changing State

Aspects of SMACSS

  1. Depth of Applicability
  2. Selector Performance
  3. HTML5 and SMACSS
  4. Prototyping
  5. Preprocessors
  6. Drop the Base
  7. The Icon Module
  8. Complicated Inheritance
  9. Screencast: Applying the Principles
  10. Screencast: Avoiding Content-specific Context


  1. Formatting Code
  2. Resources

What people have to say

“This should be required reading for anyone who opens a CSS file.”

Josh Walsh

“SMACSS is becoming one of the most useful contributions to front-end discussions in years.”

Paul Smith

“Possibly one of the best publications so far. IMO a must have for anyone working on the front end.”

Matteo Pescarin

“[SMACSS] is required reading for anyone who will ever touch CSS. Hard earned wisdom that few mavens have even mastered”

Thomas Aylott

“Snook’s book is not only highly readable, it’s chock full of examples that will help you wrangle your code into something more manageable”

Scott Gilbertson at webmonkey

“it has great thoughts on architecting maintainable CSS for larger sites”

Greg Rewis in .net magazine