css3 adaptive layout unit vw, vh how much you know?
The CSS3 specification , the viewport includes the following four units:
1.vw: 1vw equal to 1% depending on the width of the opening.
2.vh: 1vh equal to 1% of the height of the viewport.
3.vmin: Select vw and vh the smallest one.
4.vmax: Select vw and vh the largest one.
vh and vw: with respect to the height and width of the viewport, and not the parent element (CSS containing a percentage relative to its nearest parent element height and width). 1vh equal to the height of the viewport 1/100, 1vw width equal to 1/100 of the viewport.