body {
	max-width: 640px;
	width: 100%;
}

html {
	background: #f5f5f5;
	display: flex;
	justify-content: center;
}

.zsc_topics ul {
	display: flex;
	justify-content: initial;
}

.zsc_topics li {
	width: 31%;
}

.zsc_topics li:nth-child(3n+2) {
	margin-left: 3.5%;
}

.zsc_topics li:nth-child(3n+3) {
	margin-left: 3.5%;
}

footer {
	max-width: 640px;
	left: 50%;
	margin-left: -320px;
}

.zst_banner {
	height: 12rem;
}

.zst_banner img {
	height: 12rem;
}

.zsc_topics ul {
	display: flex;
	justify-content: initial;
}

.zsc_topics li {
	width: 31%;
}

.zsc_topics li:nth-child(3n+2) {
	margin-left: 3.5%;
}

.zsc_topics li:nth-child(3n+3) {
	margin-left: 3.5%;
}

footer {
	max-width: 640px;
	left: 50%;
	margin-left: -320px;
}

.zst_banner {
	height: 12rem;
}

.zst_banner img {
	height: 12rem;
}

.class_body {
	position: relative;
}

.zst_class_left {
	max-width: 160px;
	position: absolute;
	left: 0;
	display: none;
}

.zst_class_right {
	padding: 1rem 3%;
}

.zst_pc_top {
	width: 94%;
	height: 40px;
	margin: 2rem 3% 1rem;
}

.zst_pc_top ul {
	display: flex;
	justify-content: space-between;
}

.zst_pc_top ul::-webkit-scrollbar {
	height: 4px;
	background: red;
	display: none;
}

.zst_pc_top li {
	width: 18%;
	height: 40px;
	background: #fff;
	box-shadow: 0 0px 8px #e2e0e0;
	flex-shrink: 0;
	font-size: 14px;
	text-align: center;
	color: #999;
	line-height: 40px;
	border-radius: 4px;
}

.zst_pc_top li.action {
	background: #206bc4;
	color: #fff;
	box-shadow: 0 0 8px #a8cbff;
}


.zst_header {
	max-width: 640px;
	width: 100%;
	position: fixed;
	top: 0;
	left: 50%;
	margin-left: -320px;
}

.zst_details_footer{
	max-width: 640px;
	width: 100%;
	position: fixed;
	bottom: 0;
	left: 50%;
	margin-left: -320px;
}
.exam_top{
	max-width: 640px;
	width: 100%;
	position: fixed;
	top: 0;
	left: 50%;
	margin-left: -320px;
}
.syt{
	max-width: 600px;
	width: 100%;
	position: fixed;
	bottom: 32px;
	left: 50%;
	margin-left: -300px;
}
.header{
	max-width: 640px;
	width: 100%;
	position: fixed;
	top: 0;
	left: 50%;
	margin-left: -320px;
}