Catlin Hampton Lintorn - Pragmatic Guide to Sass 3: Tame the Modern Style Sheet

Copyright 2016 The Pragmatic Programmers, LLC. This book is licensed to the individual who purchased it. We don't copy-protect it because that would limit your ability to use it for your own purposes. Please don't break this trustyou can use this across all of your devices but please do not share this copy with other members of your team, with friends, or via file sharing services. Thanks.

Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in this book, and The Pragmatic Programmers, LLC was aware of a trademark claim, the designations have been printed in initial capital letters or in all capitals. The Pragmatic Starter Kit, The Pragmatic Programmer, Pragmatic Programming, Pragmatic Bookshelf and the linking g device are trademarks of The Pragmatic Programmers, LLC.

Every precaution was taken in the preparation of this book. However, the publisher assumes no responsibility for errors or omissions, or for damages that may result from the use of information (including program listings) contained herein.

The Pragmatic Bookshelf is an agile publishing company. Were here because we want to improve the lives of developers. We do this by creating timely, practical titles, written by programmers for programmers.

Our Pragmatic courses, workshops, and other products can help you and your team create better software and have more fun. For more information, as well as the latest Pragmatic titles, please visit us at http://pragprog.com.

Our ebooks do not contain any Digital Restrictions Management, and have always been DRM-free. We pioneered the beta book concept, where you can purchase and read a book while its still being written, and provide feedback to the author to help make a better book for everyone. Free resources for all purchasers include source code downloads (if applicable), errata and discussion forums, all available on the book's home page at pragprog.com. Were here to make your life easier.

Want to keep up on our latest titles and announcements, and occasional special offers? Just create an account on pragprog.com (an email address and a password is all it takes) and select the checkbox to receive newsletters. You can also follow us on twitter as @pragprog.

If you buy directly from pragprog.com, you get ebooks in all available formats for one price. You can synch your ebooks amongst all your devices (including iPhone/iPad, Android, laptops, etc.) via Dropbox. You get free updates for the life of the edition. And, of course, you can always come back and re-download your books when needed. Ebooks bought from the Amazon Kindle store are subject to Amazon's polices. Limitations in Amazon's file format may cause ebooks to display differently on different devices. For more information, please see our FAQ at pragprog.com/frequently-asked-questions/ebooks. To learn more about this book and access the free resources, go to https://pragprog.com/book/pg_sass3, the book's homepage.

Thanks for your continued support,

Dave Thomas and Andy Hunt
The Pragmatic Programmers

The team that produced this book includes: Brian P. Hogan (editor) Potomac Indexing, LLC (indexer) Nicole Abramowitz (copyeditor) Gilson Graphics (layout) Janet Furlow (producer)

For customer support, please contact .

For international rights, please contact .

Writing this edition has been a joy, no doubt due to our editor, Brian Hogan, and managing editor, Susannah Pfalzer. The whole Pragmatic Programmers team makes it a wonderful experience to write a book.

Wed like to thank our tech reviewers: Nick Capito, Javier Collado, Peter Hampton, Nick McGinness, Nouran Mhmoud, Stephen Orr, Loren Sands-Ramshaw, Matthew Sullivan, Mitchell Volk, and Matthew White.

Hampton: Sass wouldnt exist today without Natalie Weizenbaum and Chris Eppstein. Their hard work and determination have made Sass the powerhouse developer tool that it is today.

Michael: I cant thank the Sass community enough. Its a pleasure to be part of such a supporting and welcoming group of people.

Welcome to the Pragmatic Guide to Sass 3 . Sass (Syntactically Awesome Style Sheets) enables you to do amazing things with your style sheets and write more efficient, beautiful, and maintainable code.

Whats wrong with regular ol CSS? we hear you cry. The fact is that CSS, with all its power and elegance, is not designed for developer productivity. Instead, its focused on helping the browser quickly display styles as simply as possible. Theres nothing wrong with that, but its not helpful for us as developers. Thats where Sass comes into extend CSS, adding new features and syntax focused on making your life as a developer easier.

Sass isnt a replacement for CSSits a way to help us write better CSS files, which is essential for large projects. Sass helps us write clear, semantic style sheets. Sass updates our CSS development for the future. Its why our motto is CSS with Superpowers.

Sass is by far the most popular of the CSS extension languages, according to almost every survey. Its used in almost every major web project and is the basis for most modern open source style frameworks.

Sass was originally conceived in 2006 as a component of the Haml templating language, and it was the first CSS extension language. It was initially envisaged by Hampton Lintorn Catlin, but it was primarily implemented by Natalie Weizenbaum, who has also been primarily responsible for the languages advanced features and serves as the primary language designer today. Chris Eppstein rounds out the language core team, being best known for Compass and Eyeglass, two popular Sass-related projects. Well talk more about Eyeglass later. Sass has grown up a lot since that original concept! In fact, there are now multiple implementations of Sass, and its available on most platforms.