* {
  margin: 0px;
  padding: 0px;
}
.box {
  width: 1200px;
  height: 420px;
  margin-left: 1px;
  /* border: 1px solid #666; */
  overflow: hidden;
}
.list_menu {
  height: 600px;
  width: 2720px;
  list-style: none;
  overflow: hidden;
  display: block;
}
.list_menu li {
  width: 230px;
  float: left;
  /* width: 150px; */
  /* text-align: center; */
  /* height: 40px; */
  /* line-height: 40px; */
  background: #ffffff1a;
  height: 380px;
  padding-top: 30px;
  margin-right: 10px;
}

.list_menu li:last-child {
  margin-right: 0px;
}
.lef,
.rig {
  position: absolute;
  background: #ffffff1a;
  width: 22px;
  text-align: center;
  height: 80px;
  line-height: 80px;
  font-size: 14px;
  cursor: pointer;
  border-top-right-radius: 10px 35px;
  border-bottom-right-radius: 10px 35px;
  overflow: hidden;
}
.lef {
  top: 45%;
  margin-left: -650px;
  transform: rotate(180deg);
}
.rig {
  top: 45%;
  margin-left: 620px;
}