GSS is an implementation of Badros & Borning's Constraint Cascading Style Sheets.

It consists of three projects:

• Engine - orchestrates multiple Cassowary.js solvers. Usable without browser.
• Document - Integrates Engine with DOM. Use this on web pages.
• Parser - Converts GSS stylesheets to expression tree. Can be preprocessed

GSS supports the following syntaxes for defining layout rules:

• CCSS - direct constraints related to position and size of DOM elements
• VFL - horizontal and vertical spacing constraints based on Apple's Visual Format Language

Please refer to http://gridstylesheets.org/ for documentation and usage instructions.