@mixin no-placeholder() {
  &::-webkit-input-placeholder {
    /* Chrome/Opera/Safari */
    color: transparent;
    opacity: 0;
  }
  &::-moz-placeholder {
    /* Firefox 19+ */
    color: transparent;
    opacity: 0;
  }
  &:-ms-input-placeholder {
    /* IE 10+ */
    color: transparent;
    opacity: 0;
  }
  &:-moz-placeholder {
    /* Firefox 18- */
    color: transparent;
    opacity: 0;
  }
  &::placeholder {
    color: transparent;
    opacity: 0;
  }
}

@mixin setPlaceholderStyle($color: $gray-500, $fontSize: $font-size-base, $opacity: 1) {
  &::-webkit-input-placeholder {
    /* Chrome/Opera/Safari */
    color: $color;
    opacity: $opacity;
    font-size: $fontSize;
  }
  &::-moz-placeholder {
    /* Firefox 19+ */
    color: $color;
    opacity: $opacity;
    font-size: $fontSize;
  }
  &:-ms-input-placeholder {
    /* IE 10+ */
    color: $color;
    opacity: $opacity;
    font-size: $fontSize;
  }
  &:-moz-placeholder {
    /* Firefox 18- */
    color: $color;
    opacity: $opacity;
    font-size: $fontSize;
  }
  &::placeholder {
    color: $color;
    opacity: $opacity;
    font-size: $fontSize;
  }
}