.top {
  float: left;
  width: 100%;
}
.top .left {
  float: left;
  width: 15%;
  text-align: center;
  overflow: hidden;
}
.top .left .back {
  position: relative;
  left: 15px;
  width: 40rpx;
  height: 40rpx;
}
.top .cen {
  float: left;
  width: 70%;
  text-align: center;
  font-size: 36rpx;
  color: #000000;
  font-weight: 600;
}
.top .right {
  float: left;
  width: 15%;
}
