absolute-pos(t = 0, r = 0, b = 0, l = 0)
  top t
  right r
  bottom b
  left l
fixed-pos(t = 0, r = 0, b = 0, l = 0)
  absolute-pos(t, r, b, l)

block()
  float left
  width 100%
  
clearfix()
  &:after
    content ""
    display table
    clear both

word-break()
  word-break break-all
  word-wrap break-word
word-ellipsis()
  white-space nowrap
  overflow hidden
  text-overflow ellipsis

hairline-common(direction)
  content ''
  position absolute
  z-index 2
  transform-origin 100% 50%
  if direction == top
    transform scaleY(0.5) translateY(-100%)
    @media (min-resolution: 3dppx)
      transform scaleY(0.33) translateY(-100%)
  else if direction == bottom
    transform scaleY(0.5) translateY(100%)
    @media (min-resolution: 3dppx)
      transform scaleY(0.33) translateY(100%)
  else if direction == left
    transform scaleX(0.5) translateX(-100%)
    @media (min-resolution: 3dppx)
      transform scaleX(0.33) translateX(-100%)
  else if direction == right
    transform scaleX(0.5) translateX(100%)
    @media (min-resolution: 3dppx)
      transform scaleX(0.33) translateX(100%)

hairline(direction = all, color = color-border-base, radius = 0, size = border-width-base)
  if direction == top
    &::after
      hairline-common(direction)
      top 0
      left 0
      right auto
      bottom auto
      width 100%
      border-top solid size color
      transform-origin 50% 0

  else if direction == bottom
    &::before
      hairline-common(direction)
      bottom 0
      left 0
      right auto
      top auto
      width 100%
      border-bottom solid size color
      transform-origin 50% 100%

  else if direction == left
    &::after
      hairline-common(direction)
      top 0
      left 0
      right auto
      bottom auto
      border-left solid size color
      height 100%
      transform-origin 0 50%

  else if direction == right
    &::before
      hairline-common(direction)
      top 0
      right 0
      left auto
      bottom auto
      border-right solid size color
      height 100%
      transform-origin 100% 50%

  else
    &::after
      content ''
      position absolute
      top 0
      left 0
      right auto
      bottom auto
      width 200%
      height 200%
      border solid size color
      box-sizing border-box
      transform-origin 0 0
      transform scale(0.5)
      z-index 2
      if radius is a 'unit'
        border-radius radius * 2
      else
        border-radius "calc(%s * 2)" % radius

remove-hairline(direction = all)
  if direction == top
    &::after
      display none

  else if direction == bottom
    &::before
      display none

  else if direction == left
    &::after
      display none

  else if direction == right
    &::before
      display none

  else
    &::after
      display none

svg-background(svg)
  background-image url(svg)

vertical-height(height)
  height height
  line-height height