discourse/app/assets/stylesheets/common/components/buttons.css.scss

// --------------------------------------------------
// Buttons
// --------------------------------------------------

// Base
// --------------------------------------------------


.btn {
  display: inline-block;
  margin: 0;
  padding: 6px 12px;
  font-weight: 500;
  font-size: 1em;
  line-height: 18px;
  text-align: center;
  cursor: pointer;
  transition: all .25s;

  &:active {
    text-shadow: none;
  }
  &[disabled], &.disabled {
    cursor: default;
    opacity: 0.4;
  }
  .fa {
    margin-right: 7px;
  }
  &.no-text {
    .fa {
      margin-right: 0;
      line-height: 10px;
    }
  }
}

.btn.hidden {
  display: none;
}

// Default button
// --------------------------------------------------

.btn {
  border: none;
  color: $primary;
  font-weight: normal;
  background: dark-light-diff($primary, $secondary, 90%, -65%);

  &[href] {
    color: $primary;
  }
  &:hover {
    background: dark-light-diff($primary, $secondary, 65%, -75%);
    color: #fff;
  }
  &[disabled], &.disabled {
    background: dark-light-diff($primary, $secondary, 90%, -60%);
    &:hover { color: dark-light-choose(scale-color($primary, $lightness: 70%), scale-color($secondary, $lightness: 30%)); }
    cursor: not-allowed;
  }
}

// Buttons used in admin panel
// --------------------------------------------------
.btn-admin {
  text-align:left;
}

// Primary button
// --------------------------------------------------

.btn-primary {
  border: none;
  font-weight: normal;
  color: dark-light-choose(#fff, scale-color($primary, $lightness: 60%));
  background: $tertiary;

  &[href] {
    color: $secondary;
  }
  &:hover {
    color: #fff;
    background: dark-light-choose(scale-color($tertiary, $lightness: -20%), scale-color($tertiary, $lightness: -20%));
  }
  &:active {
    @include linear-gradient(scale-color($tertiary, $lightness: -20%), scale-color($tertiary, $lightness: -10%));
    color: #fff;
  }
  &[disabled], &.disabled {
    background: $tertiary;
  }
}

// Danger button
// --------------------------------------------------

.btn-danger {
  color: $secondary;
  font-weight: normal;
  background: $danger;
  &[href] {
    color: $secondary;
  }
  &:hover{
    background: scale-color($danger, $lightness: -20%);
  }
  &:active {
    @include linear-gradient(scale-color($danger, $lightness: -20%), $danger);
  }
  &[disabled], &.disabled {
    background: $danger;
  }
}

// Social buttons
// --------------------------------------------------

.btn-social {
  color: $secondary;
  text-shadow: 0 1px 0 rgba($primary, 0.2);
  box-shadow: inset 0 1px 0 rgba(0,0,0, 0.1);
  &[href] {
    color: $secondary;
  }
  &:before {
    margin-right: 9px;
    font-family: FontAwesome;
    font-size: 17px;
  }
  &.google, &.google_oauth2 {
    background: $google;
    &:before {
      content: $fa-var-google;
    }
  }
  &.facebook {
    background: $facebook;
    &:before {
      content: $fa-var-facebook;
    }
  }
  &.cas {
    background: $cas;
  }
  &.twitter {
    background: $twitter;
    &:before {
      content: $fa-var-twitter;
    }
  }
  &.yahoo {
    background: $yahoo;
    &:before {
      content: $fa-var-yahoo;
    }
  }
  &.github {
    background: $github;
    &:before {
      content: $fa-var-github;
    }
  }
}

// Button Sizes
// --------------------------------------------------

// Small

.btn-small {
  padding: 3px 6px;
  font-size: 0.857em;
  line-height: 16px;
}

// Large

.btn-large {
  padding: 9px 18px;
  font-size: 1.143em;
  line-height: 20px;
}