@layer shell {
  .app-header {
    background: var(--color-header);
    background-image: linear-gradient(90deg, var(--navy-950), var(--navy-900) 45%, var(--navy-800));
    color: var(--color-header-text);
    position: relative;
    z-index: 30;
  }

  [dir="rtl"] .app-header {
    background-image: linear-gradient(-90deg, var(--navy-950), var(--navy-900) 45%, var(--navy-800));
  }

  .app-header__inner {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    max-inline-size: var(--container-max);
    min-block-size: var(--header-height);
    margin-inline: auto;
    padding-inline: var(--gutter);
  }

  .brand {
    display: inline-flex;
    align-items: center;
    gap: var(--space-3);
    color: inherit;
    text-decoration: none;
    min-block-size: var(--touch-target);
    border-radius: var(--radius-sm);
  }

  .brand:hover {
    color: inherit;
  }

  .brand__mark {
    inline-size: 2.25rem;
    block-size: 2.25rem;
    flex: none;
  }

  .brand__text {
    display: flex;
    flex-direction: column;
    line-height: 1.2;
  }

  .brand__product {
    font-weight: 700;
    font-size: var(--text-md);
    letter-spacing: 0.01em;
  }

  .brand__area {
    color: var(--color-header-muted);
    font-size: var(--text-xs);
    font-weight: 500;
    letter-spacing: 0.04em;
    text-transform: uppercase;
  }

  :lang(ar) .brand__area {
    letter-spacing: 0;
    text-transform: none;
    font-size: var(--text-sm);
  }

  .app-nav {
    display: flex;
    align-items: stretch;
    align-self: stretch;
    margin-inline-start: var(--space-5);
  }

  .app-nav__link {
    position: relative;
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding-inline: var(--space-3);
    color: var(--color-header-muted);
    text-decoration: none;
    font-weight: 600;
    font-size: var(--text-sm);
    white-space: nowrap;
  }

  .app-nav__link:hover,
  .app-nav__link[aria-current="page"] {
    color: #ffffff;
  }

  .app-nav__link[aria-current="page"]::after {
    content: "";
    position: absolute;
    inset-inline: var(--space-3);
    inset-block-end: 0;
    block-size: 3px;
    border-radius: 3px 3px 0 0;
    background: #7fb2ff;
  }

  .app-nav__link:focus-visible {
    outline-color: #ffffff;
    outline-offset: -3px;
  }

  .count-badge {
    display: inline-grid;
    place-items: center;
    min-inline-size: 1.5rem;
    block-size: 1.375rem;
    padding-inline: 0.4rem;
    border-radius: var(--radius-pill);
    background: #ffffff;
    color: var(--navy-900);
    font-size: var(--text-xs);
    font-weight: 700;
    font-variant-numeric: tabular-nums;
  }

  .app-header__actions {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    margin-inline-start: auto;
  }

  .header-btn,
  .user-menu__trigger {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    min-block-size: var(--touch-target);
    padding-inline: var(--space-3);
    border: 1px solid rgb(255 255 255 / 0.18);
    border-radius: var(--radius-md);
    background: rgb(255 255 255 / 0.06);
    color: #ffffff;
    font-size: var(--text-sm);
    font-weight: 600;
    transition: background var(--duration-fast);
  }

  .header-btn:hover,
  .user-menu__trigger:hover,
  .user-menu__trigger[aria-expanded="true"] {
    background: rgb(255 255 255 / 0.14);
  }

  .header-btn:focus-visible,
  .user-menu__trigger:focus-visible {
    outline-color: #ffffff;
  }

  .lang-switch__short {
    display: none;
    font-weight: 700;
  }

  .header-btn--icon {
    inline-size: var(--touch-target);
    padding-inline: 0;
    justify-content: center;
  }

  /* The control always shows the theme it will switch to. */
  .theme-switch__light,
  :root[data-theme="dark"] .theme-switch__dark {
    display: none;
  }

  :root[data-theme="dark"] .theme-switch__light {
    display: block;
  }

  .user-menu {
    position: relative;
  }

  .avatar {
    display: inline-grid;
    place-items: center;
    inline-size: 1.875rem;
    block-size: 1.875rem;
    border-radius: 50%;
    background: linear-gradient(135deg, #5c9cf0, #2d68b8);
    color: #ffffff;
    font-size: var(--text-xs);
    font-weight: 700;
  }

  .avatar--lg {
    inline-size: 2.75rem;
    block-size: 2.75rem;
    font-size: var(--text-md);
  }

  .user-menu__chevron {
    inline-size: 1rem;
    block-size: 1rem;
    transition: transform var(--duration-base) var(--ease-out);
  }

  .user-menu__trigger[aria-expanded="true"] .user-menu__chevron {
    transform: rotate(180deg);
  }

  .user-menu__panel {
    position: absolute;
    inset-inline-end: 0;
    inset-block-start: calc(100% + var(--space-2));
    inline-size: min(20rem, calc(100vw - 2 * var(--space-4)));
    padding: var(--space-4);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    background: var(--color-surface);
    color: var(--color-text);
    box-shadow: var(--shadow-lg);
    animation: pop-in var(--duration-base) var(--ease-out);
  }

  .user-menu__identity {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding-block-end: var(--space-3);
    border-block-end: 1px solid var(--color-border);
  }

  .user-menu__display {
    font-weight: 650;
  }

  .user-menu__meta,
  .user-menu__tz {
    color: var(--color-text-muted);
    font-size: var(--text-sm);
  }

  .user-menu__tz {
    display: flex;
    gap: var(--space-2);
    align-items: flex-start;
    padding-block: var(--space-3);
  }

  .user-menu__tz .icon {
    margin-block-start: 0.15em;
  }

  .menu-item {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    inline-size: 100%;
    min-block-size: var(--touch-target);
    padding-inline: var(--space-3);
    border: 0;
    border-radius: var(--radius-md);
    background: var(--color-surface-muted);
    color: var(--red-800);
    font-weight: 600;
    text-align: start;
  }

  .menu-item:hover {
    background: var(--red-100);
  }

  .app-main {
    flex: 1;
    inline-size: 100%;
    max-inline-size: var(--container-max);
    margin-inline: auto;
    padding: var(--space-6) var(--gutter) var(--space-9);
  }

  .app-main:focus {
    outline: none;
  }

  .app-footer {
    padding: var(--space-5) var(--gutter);
    border-block-start: 1px solid var(--color-border);
    color: var(--color-text-subtle);
    font-size: var(--text-sm);
    text-align: center;
  }

  .connection-banner {
    position: fixed;
    inset-block-start: calc(var(--header-height) + var(--space-2));
    inset-inline: 0;
    z-index: 60;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    inline-size: fit-content;
    max-inline-size: calc(100% - 2 * var(--space-4));
    margin-inline: auto;
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-pill);
    background: var(--color-inverse-surface);
    color: var(--color-on-inverse);
    font-size: var(--text-sm);
    font-weight: 600;
    box-shadow: var(--shadow-lg);
  }

  .connection-banner--restored {
    background: var(--color-approve);
    color: var(--color-on-approve);
  }

  .connection-banner__online,
  .connection-banner--restored .connection-banner__offline {
    display: none;
  }

  .connection-banner--restored .connection-banner__online {
    display: block;
  }

  .toast-region {
    position: fixed;
    inset-block-end: var(--space-5);
    inset-inline-end: var(--space-5);
    z-index: 70;
    display: grid;
    gap: var(--space-2);
    pointer-events: none;
  }

  .toast {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    max-inline-size: 24rem;
    padding: var(--space-3) var(--space-4);
    border-radius: var(--radius-md);
    background: var(--color-inverse-surface);
    color: var(--color-on-inverse);
    font-size: var(--text-sm);
    font-weight: 500;
    box-shadow: var(--shadow-lg);
    animation: toast-in var(--duration-slow) var(--ease-out);
  }

  @keyframes pop-in {
    from {
      opacity: 0;
      transform: translateY(-4px) scale(0.98);
    }
  }

  @keyframes toast-in {
    from {
      opacity: 0;
      transform: translateY(8px);
    }
  }

  @media (max-width: 767px) {
    .brand__text {
      display: none;
    }

    /* Three header controls plus the nav have to fit a phone, so the gaps tighten first. */
    .app-header__inner {
      gap: var(--space-2);
    }

    .app-header__actions {
      gap: var(--space-1);
    }

    .app-nav {
      margin-inline-start: var(--space-1);
    }

    .user-menu__name {
      display: none;
    }

    .lang-switch__full {
      position: absolute;
      inline-size: 1px;
      block-size: 1px;
      overflow: hidden;
      clip-path: inset(50%);
      white-space: nowrap;
    }

    .lang-switch__short {
      display: inline;
    }

    .header-btn,
    .user-menu__trigger {
      padding-inline: var(--space-2);
      min-inline-size: var(--touch-target);
      justify-content: center;
    }

    .toast-region {
      inset-inline: var(--space-4);
      inset-block-end: calc(var(--space-4) + 4.5rem);
    }
  }

  /* Below this width the nav keeps its icon and its count, and drops the label. */
  @media (max-width: 479px) {
    .app-nav__link > span:not(.count-badge) {
      display: none;
    }
  }
}