.head-start {
    background: #434141;
    font-size: 14px;
    line-height: 25px;
    height: 25px;
    color: #e7e6e6;
    position: fixed;
    top: 0;
    left: 0;
    z-index: 99;
    transition: all 0.3s;
    width: 100%;
    vertical-align:top;
  }
  
  .menu-mg {
    width: 1200px;
    margin: 0 auto;
  }
  
  .fl {
    float: left;
  }
  
  .fr {
    float: right;
  }