@layer components {
  .app-topbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-md);
    padding-inline: var(--space-md);
    padding-block: var(--space-md);
    background-color: oklch(var(--lch-white) / 0.85); /* intentional: frosted glass */
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    flex-shrink: 0;
  }

  .app-topbar__back {
    inline-size: 2.5rem;
    block-size: 2.5rem;
    border-radius: var(--radius-full);
    background-color: var(--color-canvas);
    color: var(--color-ink);
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    flex-shrink: 0;

    & svg {
      inline-size: 1.25rem;
      block-size: 1.25rem;
    }
  }

  a.app-topbar__back:hover {
    background-color: var(--color-border-subtle);
  }

  .app-topbar__title {
    flex: 1;
    text-align: center;
    font-size: var(--text-lg);
    font-weight: var(--font-semibold);
    color: var(--color-ink);
    margin: 0;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  .app-topbar__notifications {
    inline-size: 2.5rem;
    block-size: 2.5rem;
    border-radius: var(--radius-full);
    background-color: var(--color-canvas);
    color: var(--color-ink-subtle);
    border: none;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    flex-shrink: 0;
    transition: background-color var(--transition-fast);

    &:hover {
      background-color: var(--color-border-subtle);
    }

    & svg {
      inline-size: 1.5rem;
      block-size: 1.5rem;
    }
  }
}