ionic-framework/ionic/components/button/modes/md.scss

// Material Design Button
// --------------------------------------------------

$button-md-font-size:                      1.4rem !default;
$button-md-min-height:                     3.6rem !default;
$button-md-padding:                        0 1.1em !default;
$button-md-box-shadow:                     0 2px 2px 0 rgba(0,0,0,.14), 0 3px 1px -2px rgba(0,0,0,.2), 0 1px 5px 0 rgba(0,0,0,.12) !default;
$button-md-box-shadow-active:              0 3px 5px rgba(0, 0, 0, 0.14), 0 3px 5px rgba(0, 0, 0, 0.21) !default;

$button-md-border-radius:                  2px !default;
$button-md-animation-curve:                cubic-bezier(0.4, 0, 0.2, 1) !default;
$button-md-transition-duration:            300ms !default;

$button-md-clear-hover-background-color:   rgba(158, 158, 158, 0.1) !default;
$button-md-clear-active-background-color:  rgba(158, 158, 158, 0.2) !default;


button,
[button] {
  border-radius: $button-md-border-radius;

  min-height: $button-md-min-height;

  padding: $button-md-padding;
  text-transform: uppercase;

  font-weight: 500;
  font-size: $button-md-font-size;
  box-shadow: $button-md-box-shadow;

  transition: box-shadow $button-md-transition-duration $button-md-animation-curve,
              background-color $button-md-transition-duration $button-md-animation-curve,
              color $button-md-transition-duration $button-md-animation-curve;

  :hover:not(.disable-hover) {
    background-color: $button-md-clear-hover-background-color;
  }

  &.activated {
    box-shadow: $button-md-box-shadow-active;
  }

  &[full] {
    border-radius: 0;
  }

  &[clear] {
    opacity: 1;
    box-shadow: none;

    &.activated {
      background-color: $button-md-clear-active-background-color;
    }
  }

  &[outline] {
    box-shadow: none;

    &.activated {
      opacity: 1;
    }
  }

  &[round] {
    border-radius: $button-round-border-radius;
    padding: $button-round-padding;
  }

  &[large] {
    padding: 0 $button-large-padding;
    min-height: $button-large-height;
    font-size: $button-large-font-size;
  }

  &[small] {
    padding: 0 $button-small-padding;
    min-height: $button-small-height;
    font-size: $button-small-font-size;
  }

  &[fab] {
    border-radius: 50%;
  }

  &.icon-only {
    padding: 0;
  }

}


// Material Design Button Color Mixin
// --------------------------------------------------

@mixin button-theme-md($color-name, $color-value) {

  button[#{$color-name}],
  [button][#{$color-name}] {

    &.activated {
      opacity: 1;
    }

    &[outline] {

      &.activated {

        @if lightness(get-color($color-name, base)) > 90 {
          $fg-color: get-color($color-name, inverse);
        } @else {
          $fg-color: get-color($color-name, base);
        }

        opacity: 1;
      }
    }

  }

}


// Generate Material Design Button Auxiliary Colors
// --------------------------------------------------

@each $color-name, $color-value in auxiliary-colors() {

  @include button-theme-md($color-name, $color-value);

}