* {
  margin: 0;
  padding: 0;
}
body {
  background-color: #323232;
  font-size: 12px;
  font-family: "微软雅黑";
}
.box1, .box2, .box3 {
  float: left;
  margin-left: 100px;
  margin-top: 100px;
}
.box1 h3, .box2 h3, .box3 h3 {
  font-family: "微软雅黑";
  font-size: 14px;
  color: #fff;
  margin-bottom: 5px;
  font-weight: 300;
}
.tab {
  width: 300px;
}
.tab ul {
  list-style: none;
}
.tab .tab-nav {
  height: 30px;
}
.tab .tab-nav li {
  float: left;
  margin-right: 5px;
  background-color: #767676;
  border-radius: 3px 3px 0 0;
}
.tab .tab-nav li a {
  display: block;
  height: 30px;
  padding: 0 20px;
  color: #fff;
  line-height: 30px;
  text-decoration: none;
}
.tab .tab-nav li.active {
  background-color: #fff;
}
.tab .tab-nav li.active a {
  color: #777;
}
.tab .content-wrap {
  background-color: #fff;
  padding: 5px;
  height: 200px;
  width: 300px;
}
.tab .content-wrap .content-item {
  position: absolute;
  height: 200px;
  display: none;
}
.tab .content-item img {
  height: 200px;
  width: 300px;
}
.tab .content-wrap .current {
  display: block;
}