@ionic/core/dist/collection/components/header/header.ios.css

Base components for Ionic

ion-header {
  display: block;
  position: relative;
  order: -1;
  width: 100%;
  z-index: 10;
}

ion-header ion-toolbar:first-of-type {
  padding-top: var(--ion-safe-area-top, 0);
}

.header-ios ion-toolbar:last-of-type {
  --border-width: 0 0 0.55px;
}

@supports (backdrop-filter: blur(0)) {
  .header-background {
    left: 0;
    right: 0;
    top: 0;
    bottom: 0;
    position: absolute;
    backdrop-filter: saturate(180%) blur(20px);
  }

  .header-translucent-ios ion-toolbar {
    --opacity: .8;
  }

  /**
   * Disable the saturation otherwise it distorts the content
   * background color when large header is not collapsed
   */
  .header-collapse-condense-inactive .header-background {
    backdrop-filter: blur(20px);
  }
}
.header-ios.ion-no-border ion-toolbar:last-of-type {
  --border-width: 0;
}

.header-collapse-condense {
  z-index: 9;
}

.header-collapse-condense ion-toolbar {
  position: sticky;
  top: 0;
}

.header-collapse-condense ion-toolbar:first-of-type {
  padding-top: 7px;
  z-index: 1;
}

/**
 * Large title toolbar should just use the content background
 * since it needs to blend in with the header above it.
 */
.header-collapse-condense ion-toolbar {
  --background: var(--ion-background-color, #fff);
  z-index: 0;
}

.header-collapse-condense ion-toolbar ion-searchbar {
  height: 48px;
  padding-top: 0px;
  padding-bottom: 13px;
}

.header-collapse-main ion-toolbar.in-toolbar ion-title,
.header-collapse-main ion-toolbar.in-toolbar ion-buttons {
  transition: all 0.2s ease-in-out;
}

.header-collapse-condense-inactive:not(.header-collapse-condense) ion-toolbar.in-toolbar ion-title,
.header-collapse-condense-inactive:not(.header-collapse-condense) ion-toolbar.in-toolbar ion-buttons.buttons-collapse {
  opacity: 0;
  pointer-events: none;
}

/**
 * There is a bug in Safari where changing
 * the opacity of an element in a scrollable container
 * while rubber-banding causes the scroll position
 * to jump to the top
 */
.header-collapse-condense-inactive.header-collapse-condense ion-toolbar.in-toolbar ion-title,
.header-collapse-condense-inactive.header-collapse-condense ion-toolbar.in-toolbar ion-buttons.buttons-collapse {
  visibility: hidden;
}