The <body> element is a special element that wraps all of the visible content on a web page. Because everything that you see is inside this tag, any rule-set that you create for the body element will apply to every element on page, unless the element itself has a rule that contradicts it. This is useful for establishing a baseline style for everything on your page.
This rule-set would make all text in your web page blue and centered.
body { text-align: center; color: blue; }
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