@mixin border-highlight {
  &:after {
    position: absolute;
    display: block;
    content: " ";
    height: 2px;
    width: 0;
    bottom: 0;
    left: 50%;
    background-color: $input-border-highlight-color;
    animation: .2s cubic-bezier(.4,0,.4,1) 10ms alternate forwards border-expand;
    transition: all .2s;
    will-change: width, left;
  }
}

@mixin border-highlight-inverse {
  &:after {
    background-color: $input-inverse-border-highlight-color;
  }
}

@mixin border-highlight-active {
  &:after {
    width: 100%;
    left: 0;
    z-index: 4;
  }
}