grammar - 見事なまでに what does it mean?

見事なまでに制服姿の人間はいなかった。

I stumbled upon this sentence in a game i was playing. As I know まで is a particle, so I dont understand what it means. I've tried searching in the dictionary, but to no luck. All help will be appreciated.

Answer

This まで is a (conjunctive) particle, and it can take the attributive form of a verb/copula and mean "(to) the extent ～", "(to) the point where ～", etc.

• あの子は一人で留守番ができるまでに成長した。


• 少しがっかりはしたけれど、怒るまでのことではない。


• 彼の意見は残酷なまでに率直だ。

So 見事なまでに literally means "to the point where (it is) wonderful".

見事なまでに can describe something truly wonderful, but it is often used sarcastically (e.g., 彼の歌は見事なまでに下手だ, 見事なまでの失敗をしてしまった). There are 40 examples of 見事なまでに on BCCWJ, which means this is a rather common phrase. Roughly half of them are used in a sarcastic manner.