problem description before,after and other pseudo-elements and pseudo-classes have no effect the environmental background of the problems and what methods you have tried Project framework: iview + vue + stylus sets up the background system, and ca...
Writing method one: .businessType: before { content: ; display: block; } method two: .businessType: before { content: ; display: table; } Why are the two writing methods different? the first writing method can not occupy a space, while the secon...
div displays the file name, and x is the I tag. Now when the mouse is over I, I need to modify the background color of div, but there is no way to select the previous element, , or can I select the first child element div in the parent div ...