_mixins.scss

@mixin button($text-color, $border-color: transparent, $background-gradient) {
  background: $background-gradient;
  border: 1px solid;
  border-color: $border-color;
  border-radius: 2px;
  width: 100%;
  text-transform: initial;
  span:first-child {
    color: $text-color;
  }
  &:hover,
  &:focus,
  &.active,
  &:disabled {
    @content;
  }
  &:disabled {
    cursor: not-allowed;
    opacity: 0.5;
  }
  transition: all 150ms ease-in-out;
}