ionic-framework/ionic/components/app/structure.scss

html,
body {
  height: 100%;
}

body {
  position: relative;
  overflow: hidden;
  max-width: 100%;
  max-height: 100%;
  margin: 0;
  padding: 0;
  word-wrap: break-word;g

  touch-action: manipulation;
  -webkit-touch-callout: none;
  -webkit-user-drag: none;
  -ms-content-zooming: none;

  -webkit-font-smoothing: antialiased;
  font-smoothing: antialiased;
  text-rendering: optimizeLegibility;

  -webkit-text-size-adjust: none;
  -moz-text-size-adjust: none;
  text-size-adjust: none;

  -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  user-select: none;

  -webkit-backface-visibility: hidden;
}

ion-app {
  display: flex;
  flex-direction: column;

  overflow: hidden;
  height: 100%;
  max-width: 100%;
  max-height: 100%;
  margin: 0;
  padding: 0;
}

ion-nav {
  height: 100%;
}

ion-pane {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;

  display: flex;
  flex-direction: column;
}

.nav-item {
  display: none;

  &.show-view {
    display: flex;
  }
}

.navbar-container {
  position: relative;
  min-height: 4.4rem;
}

.content-container {
  position: relative;
  flex: 1;
}

ion-navbar {
  position: absolute;
  width: 100%;
  height: 100%;
  min-height: 4.4rem;
  order: $flex-order-toolbar-top;

  display: none;
  &.show-navbar {
    display: flex;
  }
}

ion-toolbar {
  display: flex;
  min-height: 4.4rem;
  background: white;
}

ion-content {
  position: relative;
  display: block;
  flex: 1;
  order: $flex-order-view-content;
}

.scroll-content {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  overflow-y: auto;
  overflow-x: hidden;
  -webkit-overflow-scrolling: touch;
  will-change: scroll-position;
}


// Hardware Acceleration
.transitioning {

  ion-view,
  .ion-view,
  ion-navbar,
  .back-button,
  ion-title {
    will-change: transform, opacity;
  }

}