It is important for your Team Site to look and feel the way you want it to. There are many Theme templates that come out of the box in SharePoint 2013. You can use the templates as it is to apply to your site or you can further customize the template to give it your own look and feel including changing the background image for the site. This video shows how you can first customize and then implement a site’s new look and feel by just using the browser.
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