landing-app/landing/src/app/ui/site-header.scss

:host {
  display: block;
}

.landing-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background-color: color-mix(
    in srgb,
    var(--pi-color-white, #fff) 88%,
    transparent
  );
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--pi-color-grey-200, #e4e4ea);
}

.landing-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  height: 4rem;
}

.landing-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.625rem;
  font-weight: 700;
  text-decoration: none;
  color: inherit;
}

// The mark carries its own glow, so it needs no background of its own — and
// `alt=""` because the wordmark beside it already names the site.
.landing-brand__mark {
  width: 2rem;
  height: 2rem;
  object-fit: contain;
}

.landing-header__nav {
  display: none;
  gap: 1.75rem;

  a {
    text-decoration: none;
    color: var(--pi-color-grey-600, #5b5b6b);
    font-size: 0.9375rem;

    &:hover {
      color: inherit;
    }
  }

  @media (min-width: 900px) {
    display: flex;
  }
}

.landing-header__actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

// The library components carry their own `:host { display: … }`. Component
// styles are scoped by attribute, so specificity ties with theirs — hence the
// extra class rather than a bare one.
.landing-header .landing-header__locales,
.landing-header .landing-header__cta {
  display: none;

  @media (min-width: 640px) {
    display: inline-flex;
  }
}

@media (max-width: 899px) {
  .landing-header .landing-header__locales {
    display: none;
  }
}

// Three bars rather than `pi-hamburger`: that component translates its own
// label and is styled for the app shell's drawer, not a marketing bar.
.landing-header__toggle {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
  width: 2.25rem;
  height: 2.25rem;
  padding: 0 0.5rem;
  border: 1px solid var(--pi-color-grey-200, #e4e4ea);
  border-radius: 0.625rem;
  background: none;
  cursor: pointer;

  span {
    display: block;
    height: 1.5px;
    background-color: currentColor;
  }

  @media (min-width: 900px) {
    display: none;
  }
}

.landing-header__mobile {
  border-top: 1px solid var(--pi-color-grey-200, #e4e4ea);
  padding-block: 0.5rem;

  a {
    display: block;
    padding-block: 0.625rem;
    text-decoration: none;
    color: var(--pi-color-grey-600, #5b5b6b);
  }

  @media (min-width: 900px) {
    display: none;
  }
}

.landing-header__mobile-locales {
  display: flex;
  gap: 0.5rem;
  padding-block: 0.75rem 0.25rem;
  border-top: 1px solid var(--pi-color-grey-200, #e4e4ea);

  a {
    padding: 0.25rem 0.625rem;
    border-radius: 0.5rem;
    font-size: 0.8125rem;
    font-weight: 600;
  }

  a.is-active {
    background-color: var(--pi-color-primary-50, #ede9fe);
    color: var(--pi-color-primary, #6d5cf0);
  }
}

.landing-header .landing-header__appearance {
  display: none;

  @media (min-width: 640px) {
    display: inline-flex;
  }
}

.landing-header__mobile-appearance {
  display: block;
  width: 100%;
  padding: 0.625rem 0;
  border: 0;
  border-top: 1px solid var(--pi-color-grey-200, #e4e4ea);
  background: none;
  text-align: left;
  font: inherit;
  color: var(--pi-color-grey-600, #5b5b6b);
  cursor: pointer;
}

// A shadow under the header once the page moves, so it reads as floating over
// the content rather than as part of it. Tied to the scroll in CSS; without
// scroll-driven animations the border alone does the job, as before.
@keyframes header-lift {
  to {
    border-bottom-color: transparent;
    box-shadow: 0 10px 30px -18px
      color-mix(in srgb, var(--pi-color-primary) 45%, transparent);
  }
}

@supports (animation-timeline: scroll()) {
  @media (prefers-reduced-motion: no-preference) {
    .landing-header {
      animation: header-lift linear both;
      animation-timeline: scroll(root);
      animation-range: 0 5rem;
    }
  }
}