.nav {
  overflow: hidden;
  width: 1000px;
  margin: 0 auto;
  padding: 0;
  display: flex;
}
.nav li {
  list-style: none;
}
.nav li a {
	display: block;
	width: 200px;
	height: 35px;
	text-align: center;
	color: #fff;
	font-size: 14px;
	line-height: 2.6;
	background: #50B3C6;
	text-decoration: none;
	border-right: 1px solid #eee;
	box-sizing: border-box;
}
.nav > li:hover > a {/*layer-1*/
  color: #ED7651;
  background: #50CDE3;
}
.nav li ul {
  width: 200px;
  display: none;
  margin-left: -40px;
  position: absolute;
}
.nav > li li:hover > a {/*layer-2*/
  color: olive;
  background: #ADECEF;
}
.nav li ul li a {
  border-top: 1px solid #eee;
}
.content {
	width: 750px;
	height: 200px;
	background: #eee;
	padding: 10px;
	text-align: left;
	box-sizing: border-box;
	margin-top: 0;
	margin-right: auto;
	margin-bottom: 0;
	margin-left: auto;
}

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