nativescript-demo/app/_app-common.scss

@import '@nativescript/theme/core';
@import '@nativescript/theme/default';

// Place any CSS rules you want to apply on both iOS and Android here.
// This is where the vast majority of your CSS code goes.

// Font icon class
.fab {
  font-family: 'Font Awesome 5 Brands', 'fa-brands-400';
  font-weight: 400;
}

.fas {
  font-family: 'Font Awesome 5 Free', 'fa-solid-900';
  font-weight: 900;
}

.far {
  font-family: 'Font Awesome 5 Free', 'fa-regular-400';
  font-weight: 400;
}

// Custom tabstrip item class
.navigation__item {
  &:active,
  &:active Label {
    @include colorize($color: complementary);
  }
}

// Common page class
.page__content {
  &-icon,
  &-placeholder {
    color: const(grey);
    font-size: 20;
    vertical-align: center;
    horizontal-align: center;
  }

  &-icon {
    font-size: 72;
    vertical-align: top;
    margin-top: 20%;
  }
}