=outer-table-borders(!width = 2px, !color = black)
  border= !width "solid" !color
  thead
    th
      border-bottom= !width "solid" !color
  tfoot
    th, td
      border-top= !width "solid" !color
  th
    &:first-child
      border-right= !width "solid" !color

=inner-table-borders(!width = 2px, !color = black)
  th, td
    border:
      right= !width "solid" !color
      bottom= !width "solid" !color
      left-width: 0px
      top-width: 0px
    &:last-child,
    &.last
      border-right-width: 0px
  tbody, tfoot
    tr:last-child,
    tr.last
      th, td
        border-bottom-width: 0px