If it doesn't work, try reloading a few times but it's also possible that it won't work in your browser
https://scratch.mit.edu/discuss/topic/875554/ When Scratch loads the costumes, it temporarily injects their code into the website, but it removes it within the same frame. @fortyonegames and @Yoshiii999 discovered that the styles in a CSS can stay on the page longer. I've seen this used to make dark mode at https://scratch.mit.edu/projects/1304851914 and I thought I'll also make my own The way it works is that there are two different costumes, one that has the styles that I want to apply, and one that has extremely long transitions for the styles, which makes them stay applied. If a costume with the transitions finishes loading right after the costume with the styles (but within the same frame), the browser will start doing the transitions from the costume's styles into Scratch's default styles. Some browsers continue doing the transition even after Scratch removes the transition costume's CSS from the page.
