Template:Rainbow Header

<h2 style="border-bottom: Orange 2px solid; text-align: center; border-left: Orange 2px solid; padding-bottom: 0.2em; margin: 0px 0px 10px; padding-left: 0.4em; padding-right: 0.4em; background: -moz-linear-gradient(left, red, orange, yellow, green, blue, indigo, violet); background: -webkit-gradient(linear, left center, right center, from(red), color-stop(14%, orange), color-stop(20%, yellow), color-stop(42%, green), color-stop(56%, blue), color-stop(70%, indigo), to(violet)); color: white; font-size: 150%; border-top: Gold 3px solid; font-weight: bold; border-right: Gold 3px solid; padding-top: 0.2em; -moz-border-radius: 3px; border-radius: 3px;">

Documentation
"title" being what you want it to say. It will show: