Cascading Style Sheets, or CSS, is a language used to specify the visual appearance of a Web page—in contrast to HTML (HyperText Markup Language), which is a markup language that defines the structure of a document for distribution on the Web. HTML tells a Web browser how the content is organized on the page, whereas CSS tells the browser how it should look. CSS3, an abbreviation for CSS Level 3, is the next generation of this style language that adds several new capabilities. It may still be under development by the W3C (World Wide Web Consortium), but CSS3 has already taken its place alongside HTML5 at the forefront of all cutting-edge Web design.
|w3-row||Container for one row of fluid responsive content|
|w3-row-padding||Row where all columns have a default padding|
|w3-content||Container for fixed size centered content|
|w3-half||Half (1/2) screen column container|
|w3-third||Third (1/3) screen column container|
|w3-twothird||Two third (2/3) screen column container|
|w3-quarter||Quarter (1/4) screen column container|
|w3-threequarter||Three quarters (3/4) screen column container|
|w3-col||Column container for any HTML content|
|w3-rest||Occupies the rest of the column width|
|l1 - l12||Responsive sizes for large screens|
|m1 - m12||Responsive sizes for medium screens|
|s1 - s12||Responsive sizes for small screens|
|w3-hide-small||Hide content on small screens (less than 601px)|
|w3-hide-medium||Hide content on medium screens|
|w3-hide-large||Hide content on large screens (larger than 992px)|
|w3-mobile||Adds mobile-first responsiveness to any element.
Displays elements as block elements on mobile devices.