$resizer-extend = 4px
$resizer-extend-color = rgba($primary-color, 0.3)

.Resizer
  background: #000
  opacity: .2
  z-index: 1
  box-sizing: border-box
  background-clip: padding-box

.Resizer.horizontal
  height: ($resizer-extend * 2 + 1px)
  margin: -($resizer-extend) 0
  border-top: $resizer-extend solid transparent
  border-bottom: $resizer-extend solid transparent
  cursor: row-resize
  width: 100%

.Resizer.vertical
  width: ($resizer-extend * 2 + 1px)
  margin: 0 -($resizer-extend)
  border-left: $resizer-extend solid transparent
  border-right: $resizer-extend solid transparent
  cursor: col-resize

.Resizer:hover
  border-color: $resizer-extend-color