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

// Z-Index
// --------------------------------------------------
// Grouped by elements which would be siblings

$z-index-menu-overlay:           80;
$z-index-menu-backdrop:          79;
$z-index-overlay:                1000;
$z-index-click-block:            9999;

$z-index-content-section:        5;
$z-index-navbar-section:         10;

$z-index-content:                5;
$z-index-toolbar:                10;
$z-index-toolbar-background:     -1;

$z-index-toolbar-border:         20;
$z-index-list-border:            50;

$z-index-backdrop:               1;
$z-index-overlay-wrapper:        10;


$z-index-item-options:           1;

// Flex Order
// --------------------------------------------------

$flex-order-view-content:        0;

$flex-order-toolbar-top:         -10;
$flex-order-toolbar-bottom:      10;

$flex-order-tab-bar-navbar:      -30;
$flex-order-tab-bar-top:         -20;
$flex-order-tab-bar-bottom:      20;



// App Structure
// --------------------------------------------------

* {
  box-sizing: border-box;
  -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
  -webkit-tap-highlight-color: transparent;
  -webkit-touch-callout: none;
}

html {
  width: 100%;
  height: 100%;
  -ms-text-size-adjust: 100%; // 1
  -webkit-text-size-adjust: 100%; // 1
}

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

  touch-action: manipulation;
  -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;

  @include user-select-none();
}

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

  display: flex;
  flex-direction: column;
}

ion-view.pane-view {
  background: transparent;
}

ion-view {
  display: none;
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  flex-direction: column;

  background-color: $background-color;

  transform: translateZ(0px);

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

[no-navbar] > ion-navbar-section {
  display: none;
}

ion-navbar-section {
  position: relative;
  min-height: 4.4rem;
  z-index: $z-index-navbar-section;
}

ion-content-section {
  position: relative;
  z-index: $z-index-content-section;
  flex: 1;
  order: $flex-order-view-content;
}

[hidden],
template,
root-anchor {
  display: none !important;
}