Let's say you need a gradient border around an element. My mind goes like this:
- There is no simple obvious CSS API for this.
- I'll just make a wrapper element with a
linear-gradientbackground, then an inner element will block out most of that background, except a thin line of padding around it.
Perhaps like this:
If you hate the idea of a wrapping element, you could use a pseudo-element, as long as a negative z-index value is OK (it wouldn't be if there was much nesting going on with parent elements with their own backgrounds).
Here's a Stephen Shaw example of that, tackling
border-radius in the process:
You could even place individual sides as skinny pseudo-element rectangles if you didn't need all four sides.
But don't totally forget about
border-image, perhaps the most obtuse CSS property of all time. You can use it to get gradient borders even on individual sides:
Using both border-image and border-image-slice is probably the easiest possible syntax for a gradient border, it's just incompatible with