Header, three equal columns and a footer. On smaller screens, the columns will stack on top of each other.

Header

Column
Column
Column

CSS Template using Flexbox

In this example, we have created a header, three unequal columns and a footer. On smaller screens, the columns will stack on top of each other. Resize the browser window to see the responsive effect.

Note: Flexbox is not supported in Internet Explorer 10 and earlier versions.

Header

Column
Column
Column