A default stylesheet based on GitHub’s Markdown formatting for use with BBEdit’s Preview CSS feature.

DefaultCSS_Markdown.css

body {
	background-color: #FFF;
	color: #333;
	font: 15px Helvetica, arial, freesans, clean, sans-serif;
	word-wrap: break-word;
	line-height: 1.7;
	padding: 0 20px 20px 20px;
	max-width: 1200px;
	margin: 0 auto;
	-webkit-font-smoothing: antialiased;
}

a {
	color: #4183c4;
	text-decoration: none;
}

a:hover {
	text-decoration: underline;
}

p, blockquote, ul, ol, dl, table, pre {
	margin: 15px 0;
}

ul, ol {
	padding-left: 30px;
}

h1 {
	border-bottom: 1px solid #ddd;
	color: #000;
	font-size: 2.5em;
}

h2 {
	border-bottom: 1px solid #eee;
	color: #000;
	font-size: 2.0em;
}

h3 {
	font-size: 1.5em;
}

h4 {
	font-size: 1.2em;
}

h5 {
	font-size: 1.0em;
}

h6 {
	color: #777;
	font-size: 1.0em;
}

h1, h2, h3, h4, h5, h6 {
	font-weight: bold;
	line-height: 1.7;
	margin: 1em 0 15px 0;
}

h1 + p, h2 + p, h3 + p {
	margin-top: 10px;
}	

img {
	width: 100%;
}

code {
	background: rgba(0,0,0,0.02);
	padding: 2px;
	border-radius: 3px;
	border: 1px solid rgba(0,0,0,0.1);
	cursor: text;
}

pre {
  	background: rgba(0,0,0,0.02);
	padding: 10px;
	border-radius: 3px;
	margin: 20px 0;
	border: 1px solid rgba(0,0,0,0.1);
	cursor: text;
	overflow: scroll;
}
 
pre code {
	background: transparent;
	border: none;
}