spee.ch/client/scss/_button-primary.scss

.button--primary, .button--primary:focus, .button--primary:active {
  border-color: $primary-color;
  color: $primary-color;
  background-color: $background-color;
}

.button--primary:hover {
  color: $background-color;
  background-color: $primary-color;
}

.button--primary:active {
  $color: darken($primary-color, 10%);
  border-color: $color;
  background-color: $color;
}