Help:Headings

From EnablerWiki

Headings can be formatted by editing the css style sheet for the current skin (monobook by default)

Look for the section:

h1, h2, h3, h4, h5, h6 {
	color: #cc0066;
	background: none;
	font-weight: normal;
	margin: 0;
	padding-top: .5em;
	padding-bottom: .17em;
	border-bottom: 1px solid #aaa;
}
h1 { font-size: 188%; }
h1 .editsection { font-size: 53%; }
h2 { font-size: 150%; }
h2 .editsection { font-size: 67%; }
h3, h4, h5, h6 {
	border-bottom: none;
	font-weight: bold;
}
h3 { font-size: 132%; }
h3 .editsection { font-size: 76%; font-weight: normal; }
h4 { font-size: 116%; }
h4 .editsection { font-size: 86%; font-weight: normal; }
h5 { font-size: 100%; }
h5 .editsection { font-weight: normal; }
h6 { font-size: 80%;  }
h6 .editsection { font-size: 125%; font-weight: normal; }