I looked for what characters are valid in CSS style names and found a few questions/posts, such as:
Which characters are valid in CSS class names/selectors?
Can I safely use unicode characters (e.g. accents) in CSS class names or ids?
https://css-tricks.com/unicode-class-names/
All these suggest accented and other unicode characters can be used in css style names. However I found the begavior is different in Safari and other browsers. e.g. with characters such as Ø Ö Ä ñ in css style names, Safari does not apply the style, but chrome, firfox, edge do.
Then I checked these style names with CSS-Validator, and it does give error.
So can't we use these characters normally, without unicode escaping? Are only ascii characters valid in css style names?