If you have only one clause, using a negated clause is strictly superior. The only reason to go fractional is if you have multiple clauses, since Level 3 only s

If you have only one clause, using a negated clause is strictly superior. The only reason to go fractional is if you have multiple clauses, since Level 3 only supported negation of the entire thing. I think that’s why using negation has never been particularly common, because people sometimes like to basically do `(width >= 480px) and (width < 768px)`. (In my experience, you’re normally better stacking the queries—e.g. mobile default, then (min-width: 480px), then (min-width: 768px)—rather than attempting to apply them exclusively, though there are certainly sometimes reasons to do it otherwise.)