// button option
[class^="is-button"]
  &.is-block
    display: block
    width: 100%
  &.has-image
    height: auto
  .is-button-note
    +inline-block
    +rem('font-size', 12px)
    +rem('margin-left', 6px)

// button-group
.is-button-group
  font-size: 0
  >li
    display: inline
    letter-spacing: normal
    font-size: 0
    [class^="is-button"]
      +border-radius(0)
    &:first-child
      [class^="is-button"]
        +border-left-radius(4px)
    &:last-child
      [class^="is-button"]
        +border-right-radius(4px)