Zotero has over 8,000 different citation styles preformatted that can be added to your quick list of citation styles. In addition to standard styles like APA, Chicago, Harvard and CSE, the Zotero style repository has journal-specific styles like PloS Biology, Journal of Egyptian History, and Frontiers in Laboratory Medicine too (and many more).
Installing New Styles:
1.) To install new styles, go to your Zotero >> Preferences.
2.) Once the Preferences window is open, click the Cite tab and toggle to Styles. Click "Get additional styles..."
3.) This will prompt the Zotero Style Repository to open. Using the Repository you can search for a style by name or browse by field or format.
4.) Once you've found a style you'd like to install, simply click on the style name and it will automatically add the style to your list.