{{Startcenter}} starts a centered section on a page by transcluding:

<div class="center" style="width:auto;margin-left:auto;margin-right:auto;">

(compare {{Center}}).

Use {{endcenter}} to insert a </div> to end the section. Further styling may be included via the first unnamed parameter or, taking precedence, by using |style=. Similarly, further classes may be added using |class=.

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