"Classical style" or "retro style"。
“古典風格”是"classical style" 。
“復古風格”是 "retro style"。
解釋：
classical style
[詞典] 古典風格;
[例句]From the classical style changes also was designed to extract concise wear fashionable for brides, provides many choices.
款式變化也從經典隆重設計中提煉出簡潔易穿的時髦款，為新娘們提供了多多選擇。
retro style ?
[詞典] ? 復古風; 復古風格;
[例句]Taiwan kicked off the new year in retro style, with a bank run that looked more 1997 than 2007.
臺灣似乎以壹種復古方式開始新年：這裏發生的銀行擠兌事件，更像是在1997年，而非2007年。