.hairline-common() { position: absolute; box-sizing: border-box; content: ' '; pointer-events: none; } .hairline(@border-color: #ebedf0) { .hairline-common(); top: -50%; right: -50%; bottom: -50%; left: -50%; border: 0 solid @border-color; transform: scale(0.5); } .hairline-bottom(@border-color: #ebedf0, @left: 0) { .hairline-common(); right: 0; bottom: 0; left: @left; border-bottom: 1px solid @border-color; transform: scaleY(0.5); }