(CSS) `unicode-range` keyword not supported

[kshetline]

Describe the issue

CSS unicode-range is not recognized, and subsequent range values are badly parsed.

Which language seems to have the issue?

CSS

Are you using highlight or highlightAuto?

highlight

Sample Code to Reproduce

@font-face {
  font-family: DroidSans;
  src: url(DroidSans.ttf);
  unicode-range: U+000-5FF, U+1e00-1fff, U+2000-2300;
}

Gets highlighted this way:

Expected behavior

More like the way GitHub shows the code above.

[divyam-r25]

Hii @kshetline, I would like to work on this issue,can you please assign me this issue