@layer components {
  site-nav {
    display: block;
    position: sticky;
    top: 0;
    z-index: 100;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
  }

  .nav__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-block: var(--space-4);
  }

  .nav__logo {
    font-size: var(--text-lg);
    font-weight: 700;
    color: var(--color-text-primary);
    text-decoration: none;
    letter-spacing: -0.02em;
    transition: color var(--ease-fast);
  }

  .nav__logo:hover { color: var(--color-accent); }

  .nav__right {
    display: flex;
    align-items: center;
    gap: var(--space-6);
  }

  .nav__links {
    display: flex;
    list-style: none;
    padding: 0;
    gap: var(--space-6);
    align-items: center;
  }

  .nav__link {
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--color-text-secondary);
    text-decoration: none;
    transition: color var(--ease-fast);
  }

  .nav__link:hover,
  .nav__link[aria-current="page"] { color: var(--color-accent); }

  .nav__controls {
    display: flex;
    align-items: center;
    gap: var(--space-1);
  }

  .nav__qr,
  .nav__theme,
  .nav__toggle {
    display: flex;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-2);
    color: var(--color-text-primary);
    border-radius: var(--radius-sm);
    transition: color var(--ease-fast), background var(--ease-fast);
  }

  .nav__qr:hover,
  .nav__theme:hover,
  .nav__toggle:hover { color: var(--color-accent); }

  .nav__toggle { display: none; }

  /* Theme toggle icons */
  .theme-icon--sun  { display: none; }
  .theme-icon--moon { display: block; }

  [data-theme="dark"] .theme-icon--sun  { display: block; }
  [data-theme="dark"] .theme-icon--moon { display: none;  }

  @media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) .theme-icon--sun  { display: block; }
    :root:not([data-theme="light"]) .theme-icon--moon { display: none;  }
  }

  @media (max-width: 640px) {
    .nav__toggle { display: flex; }

    .nav__links {
      display: none;
      position: absolute;
      top: 100%;
      left: 0;
      right: 0;
      background: var(--color-surface);
      border-bottom: 1px solid var(--color-border);
      padding: var(--space-4) var(--container-padding);
      flex-direction: column;
      align-items: flex-start;
      gap: var(--space-4);
    }

    .nav__links.is-open { display: flex; }
  }

  /* QR modal */
  @keyframes qr-backdrop-in {
    from { background: rgb(0 0 0 / 0); }
    to   { background: rgb(0 0 0 / 0.5); }
  }

  @keyframes qr-box-in {
    from { opacity: 0; transform: scale(0.93) translateY(8px); }
    to   { opacity: 1; transform: scale(1)    translateY(0); }
  }

  .qr-modal {
    position: fixed;
    inset: 0;
    z-index: 200;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgb(0 0 0 / 0.5);
    animation: qr-backdrop-in 220ms ease both;
  }

  .qr-modal.is-closing {
    animation: qr-backdrop-in 180ms ease reverse both;
    pointer-events: none;
  }

  .qr-modal[hidden] { display: none; }

  .qr-modal__box {
    position: relative;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-8);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-4);
    box-shadow: var(--shadow-lift);
    animation: qr-box-in 220ms var(--ease-base) both;
  }

  .qr-modal.is-closing .qr-modal__box {
    animation: qr-box-in 180ms ease reverse both;
  }

  .qr-modal__close {
    position: absolute;
    top: var(--space-3);
    right: var(--space-3);
    display: flex;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-1);
    color: var(--color-text-secondary);
    border-radius: var(--radius-sm);
    transition: color var(--ease-fast);
  }

  .qr-modal__close:hover { color: var(--color-text-primary); }

  .qr-modal__img {
    display: block;
    border-radius: var(--radius-sm);
  }

  .qr-modal__url {
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    font-family: var(--font-mono);
  }
}