How apply this border gradient?
I'm trying to solve it using https://css-tricks.com/gradient-borders-in-css/ and https://theodorusclarence.com/blog/gradient-border-is-hard but I'm not getting to do it. Can anyone help me please?
the button background is a background using a linear-gradient that to have opacity
the button background is a background using a linear-gradient that to have opacity

CSS-TricksChris Coyier
Let's say you need a gradient border around an element. My mind goes like this:
theodorusclarence.com
A simple gradient border is not as simple as it seems.
