1像素边框

.menuNav{
        // display: none;
        position: absolute;
        left: 0;
        top: @H;
        z-index: 999;
        box-sizing: border-box;
        padding: 0 .56rem;
        width: 200%;
        background: @BG;
      li {
        line-height: 1.8rem;
        text-align: center;
        color: #FFF;
        font-size: .56rem;
        border-top: .01rem solid #464646;
      }
      transform-origin: left top 0;
      transform: scale(0.5);
    }

整体变成2倍 然后通过 

transform-origin: left top 0;
      transform: scale(0.5);  缩放