The aim of this article is to show how to use vw and vh, and how they're not like the percentages you know.
vhunit can be used to fill the background of the viewport, aka the browser window.
heightproperty sets the background to the full height of the viewport. The
vhunit uses percentages, so
100vhis 100% of the viewport.
vwunit can be used to fill viewport backgrounds for horizontally-scrolling sites.
widthproperty sets the background to the full width of the viewport, again as a percentage. The container div's
widthproperty has a value of
200vw, 200% of the viewport width, enough to contain the two floated divs.
Browsers that support
vh include Chrome 49+, IE11, Edge 16+, Firefox 49+, Safari 11.1+, iOS Safari 10.3+ and Chrome for Android 66+.