So far I have to do this:
到目前为止,我必须这样做:
elem.classList.add("first");
elem.classList.add("second");
elem.classList.add("third");
eleSo far I have to do this:
到目前为止,我必须这样做:
elem.classList.add("first");
elem.classList.add("second");
elem.classList.add("third");
ele