CSS3 is the latest evolution of the Cascading Style Sheets language and aims at extending CSS2.1. It brings a lot of long-awaited novelties, like rounded corners, shadows, gradients, transitions or animations, as well as new layouts like multi-columns, flexible box or grid layouts. The following are just a few benefits to using CSS3.
Simple and Independent
Unlike CSS2 (which came as one big package), CSS3 is made of small modules which makes the application easier and simpler to use. Selectors, Color, Box Model, Backgrounds and Borders, Text Effects, 2D/3D Transformations and user interface are some of the most useful modules that CSS3 offers.