How is this habrahabr menu implemented?

Question

css

throw off the code of the "opener" menu on click / click on pure html5 ccs3.

Answer 1

Like everywhere else, like any hide/show object.
On button click, the show class is added to the menu object and the overlay layer.
If it is not clear, then just open the debugger and see how it is implemented.
It's harder to ask than pressing ctrl+shift+i , isn't it?
And of course, a super-duper example
tympanus.net/Development/OffCanvasMenuEffects
tympanus.net/Development/ElasticSVGElements

Answer 2

It's called a navigation drawer.

Answer 3

www.unheap.com/section/navigation

Answer 4

On pure html5 + ccs3 without js, it is done with the help of a checkbox.