BluCSS is a lightweight CSS framework designed with ease of use and simplicity in mind. It is also extremely responsive with four distinct stages: Desktop screen, laptop, tablet, and mobile.
There are 10 columns in BluCSS, and each has a width specified in percentages. Because of this, they resize automatically to fit into their parent container. In this way, you aren't restricted to just using the built-in "container" div. You can create smaller containers, and use BluCSS inside them with no changes whatsoever.