http://stovoxeobzeebmcgomjymnk73vcarxkikwo26lvfbaxmxbtjbe7umnid.onion/questions/491052/minimum-and-maximum-value-of-z-index
So if you have: < div id = "1" > < a id = "2" style = "z-index:2" > < / a > < div id = "3" style = "z-index:1" > < / d i v > < button id = "4" > < / b u t t o n > < / d i v > item #3, or even #4, may be contesting #2 for the click/hover space, though if you set #1 to z-index 0, the siblings who's z-index put them in independant stacks now are in the same stack and will z-index properly. This has a helpful and fairly humanized description:...