grafana/public/sass/mixins/_buttons.scss

// Button backgrounds
// ------------------
@mixin buttonBackground($startColor, $endColor, $text-color: #fff, $textShadow: 0px 1px 0 rgba(0,0,0,0.1)) {
  // gradientBar will set the background to a pleasing blend of these, to support IE<=9
  @include gradientBar($startColor, $endColor, $text-color, $textShadow);

  // in these cases the gradient won't cover the background, so we override
  &:hover,
  &:focus,
  &:active,
  &.active,
  &.disabled,
  &[disabled] {
    color: $text-color;
    background-image: none;
    background-color: $startColor;
  }
}

// Button sizes
@mixin button-size($padding-y, $padding-x, $font-size, $border-radius) {
  padding: $padding-y $padding-x;
  font-size: $font-size;
  //box-shadow: inset 0 (-$padding-y/3) rgba(0,0,0,0.15);

  @include border-radius($border-radius);
}

@mixin button-outline-variant($color) {
  color: $color;
  background-image: none;
  background-color: transparent;
  border-color: $color;

  @include hover {
    color: #fff;
    background-color: $color;
    border-color: $color;
  }

  &:focus,
  &.focus {
    color: #fff;
    background-color: $color;
    border-color: $color;
  }

  &:active,
  &.active,
  .open > &.dropdown-toggle {
    color: #fff;
    background-color: $color;
    border-color: $color;

    &:hover,
    &:focus,
    &.focus {
      color: #fff;
      background-color: darken($color, 17%);
      border-color: darken($color, 25%);
    }
  }

  &.disabled,
  &:disabled {
    &:focus,
    &.focus {
      border-color: lighten($color, 20%);
    }
    @include hover {
      border-color: lighten($color, 20%);
    }
  }
}