.wrap{
	width: 1200px;
	margin: 50px auto;
}
h2{
	font-size: 24px;
	line-height: 300%;
	color: #09c;
}
h3{
	xtext-indent: 2em;
	font-size: 20px;
	line-height: 150%;
}
h3 span{
	
	font-weight: bold;
}
li{
	font-size: 18px;
	line-height: 200%;
}
.box{
	margin-top: 20px;
	padding: 15px 20px;
	background: #f1f1f1;
	border: 1px solid #ddd;
}
.number li{
	counter-increment: numberlist
}
.number li:before{
	content: counter(numberlist);
	display: inline-block;
	vertical-align: middle;
	width: 24px;
	height: 24px;
	border-radius: 50%;
	background: #c00;
	font-size: 14px;
	margin-right: 10px;
	color: #fff;
	line-height: 24px;
	text-align: center;
}
.custom_number li{
	counter-increment: custom_list
}
.custom_number li:before,.custom_number li span{
	content: "第"counter(custom_list)"章："
}
.letter_number li{
	counter-increment: letter_list
}
.letter_number li:before,.letter_number li span{
	content:counter(letter_list,upper-alpha)"、";
}