Some social plugins have the option to change the way they look for sites that have a dark background.
The Share button lets people add a personalized message to links before sharing on their timeline, in groups, or to their friends via a Facebook Message.
A single click on the Like button will ‘like’ pieces of content on the web and share them on Facebook. You can also display a Share button next to the Like button to let people add a personal message and customize who they share with.
The Page plugin lets you easily embed and promote any Facebook Page on your website. Just like on Facebook, your visitors can like and share the Page without leaving your site.