/* ============================================================
   COMPONENTS
   Nav, mobile bottom nav, theme toggle, footer, buttons, tags.
   Depends on tokens.css and base.css.
   ============================================================ */

@layer components {

  /* ==================================================
     NAV (desktop, top)
     ================================================== */
  .nav {
    position: fixed; inset: 0 0 auto 0;
    display: flex; align-items: center; justify-content: space-between;
    padding: var(--s-3) var(--edge);
    z-index: 100;
    background: color-mix(in oklab, var(--bg) 82%, transparent);
    backdrop-filter: saturate(140%) blur(10px);
    -webkit-backdrop-filter: saturate(140%) blur(10px);
    border-bottom: 1px solid transparent;
    transition: border-color var(--t-med) var(--ease);
    view-transition-name: nav;
  }
  .nav.is-scrolled { border-bottom-color: var(--line); }

  .nav__logo {
    display: inline-flex;
    align-items: center;
    gap: var(--s-2);
    color: var(--fg);
    view-transition-name: logo;
  }
  .nav__mark {
    display: block;
    flex-shrink: 0;
    transition: transform var(--t-fast) var(--ease);
  }
  .nav__logo:hover .nav__mark { transform: translateY(-1px); }
  .nav__wordmark {
    font-family: 'Young Serif', serif;
    font-size: 1.125rem;
    letter-spacing: var(--track-tight);
  }
  @media (max-width: 520px) {
    .nav__wordmark { display: none; }
  }

  .nav__list {
    display: flex; gap: var(--s-5);
    list-style: none;
    font-size: var(--fs-small);
    letter-spacing: var(--track-wide);
    text-transform: uppercase;
  }
  .nav__list a {
    position: relative;
    color: var(--mid);
    padding: var(--s-2) 0;
    transition: color var(--t-fast) var(--ease);
  }
  .nav__list a:hover,
  .nav__list a[aria-current="page"] { color: var(--fg); }
  .nav__list a[aria-current="page"]::after {
    content: "";
    position: absolute; left: 0; right: 0; bottom: 0;
    height: 1px; background: var(--fg);
  }

  .nav__right { display: flex; align-items: center; gap: var(--s-3); }

  /* ==================================================
     THEME TOGGLE
     ================================================== */
  .theme-toggle {
    width: 34px; height: 34px;
    border: 1px solid var(--line);
    border-radius: 999px;
    display: inline-grid; place-items: center;
    cursor: pointer;
    transition: background var(--t-fast) var(--ease),
                border-color var(--t-fast) var(--ease);
  }
  .theme-toggle:hover {
    background: var(--tint);
    border-color: var(--fg);
  }
  .theme-toggle svg { width: 14px; height: 14px; }
  .theme-toggle .icon-sun  { display: none; }
  .theme-toggle .icon-moon { display: block; }
  :root.dark .theme-toggle .icon-sun  { display: block; }
  :root.dark .theme-toggle .icon-moon { display: none; }

  /* ==================================================
     NAV (mobile, bottom bar)
     ================================================== */
  .nav-mobile { display: none; }

  @media (max-width: 800px) {
    .nav__list { display: none; }

    .nav-mobile {
      display: block;
      position: fixed; inset: auto 0 0 0;
      padding: var(--s-2) var(--edge);
      padding-bottom: max(var(--s-2), env(safe-area-inset-bottom));
      background: color-mix(in oklab, var(--bg) 88%, transparent);
      backdrop-filter: saturate(140%) blur(14px);
      -webkit-backdrop-filter: saturate(140%) blur(14px);
      border-top: 1px solid var(--line);
      z-index: 100;
    }

    .nav-mobile__list {
      display: grid;
      grid-template-columns: repeat(5, 1fr);
      gap: var(--s-1);
      list-style: none;
    }

    .nav-mobile__list a {
      display: flex; flex-direction: column;
      align-items: center; justify-content: center;
      gap: 3px;
      min-height: 48px;
      padding: 6px 2px;
      color: var(--mid);
      font-size: 0.625rem;
      letter-spacing: 0.1em;
      text-transform: uppercase;
      transition: color var(--t-fast) var(--ease);
    }
    .nav-mobile__list a[aria-current="page"] { color: var(--fg); }
    .nav-mobile__list svg { width: 18px; height: 18px; opacity: 0.65; }
    .nav-mobile__list a[aria-current="page"] svg { opacity: 1; }

    main { padding-bottom: 80px; }
  }

  /* ==================================================
     FOOTER
     ================================================== */
  .footer {
    margin-top: var(--section);
    padding: var(--s-5) var(--edge) var(--s-5);
    border-top: 1px solid var(--line);
    display: flex; justify-content: space-between; align-items: baseline;
    gap: var(--s-4);
    font-size: var(--fs-small);
    color: var(--mid);
  }
  .footer__brand {
    font-family: 'Young Serif', serif;
    color: var(--fg);
  }
  .footer__meta { display: flex; gap: var(--s-4); }

  @media (max-width: 600px) {
    .footer {
      flex-direction: column;
      align-items: flex-start;
      gap: var(--s-3);
    }
  }

  /* ==================================================
     BUTTON
     ================================================== */
  .btn {
    display: inline-flex; align-items: center; gap: var(--s-2);
    padding: 0.75rem 1.25rem;
    border: 1px solid var(--fg);
    color: var(--fg); background: transparent;
    font-size: var(--fs-small);
    letter-spacing: var(--track-wide);
    text-transform: uppercase;
    cursor: pointer;
    transition: background var(--t-fast) var(--ease),
                color var(--t-fast) var(--ease),
                border-color var(--t-fast) var(--ease);
  }
  .btn:hover { background: var(--fg); color: var(--bg); }
  .btn svg { width: 14px; height: 14px; }

  .btn--quiet {
    border-color: var(--line);
    color: var(--mid);
  }
  .btn--quiet:hover {
    background: transparent;
    border-color: var(--fg);
    color: var(--fg);
  }

  /* Copy-to-clipboard inline affordance */
  .copy-btn {
    display: inline-flex; align-items: center; gap: 6px;
    padding: 4px 10px;
    font-size: 0.75rem;
    color: var(--mid);
    border: 1px solid var(--line);
    border-radius: 4px;
    transition: color var(--t-fast) var(--ease),
                border-color var(--t-fast) var(--ease);
  }
  .copy-btn:hover { color: var(--fg); border-color: var(--fg); }
  .copy-btn.is-copied { color: var(--fg); border-color: var(--fg); }

  /* ==================================================
     TAG / BADGE
     ================================================== */
  .tag {
    display: inline-flex; align-items: center; gap: 6px;
    padding: 3px 10px;
    border: 1px solid var(--line);
    border-radius: 999px;
    font-size: 0.75rem;
    letter-spacing: 0.02em;
    color: var(--mid);
    line-height: 1.6;
  }
  .tag--dot::before {
    content: "";
    width: 6px; height: 6px;
    border-radius: 50%;
    background: var(--mid);
  }
  .tag--live::before {
    background: oklch(0.70 0.15 145);
    animation: pulse 2.2s ease-in-out infinite;
  }
  @keyframes pulse {
    0%, 100% { opacity: 1; }
    50%      { opacity: 0.3; }
  }

  /* ==================================================
     INLINE LINK
     Subtle underlined link used inside prose.
     ================================================== */
  .inline-link {
    color: var(--fg);
    border-bottom: 1px solid var(--line);
    padding-bottom: 1px;
    transition: border-color var(--t-fast) var(--ease);
  }
  .inline-link:hover {
    border-bottom-color: var(--fg);
  }

  /* ==================================================
     ATMOSPHERE CANVAS
     Fixed background, low-opacity particle field.
     Rendered behind all content by atmosphere.js.
     ================================================== */
  .atmosphere {
    position: fixed;
    inset: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 0;
    opacity: 0.45;
  }
  main, .nav, .footer, .nav-mobile { position: relative; z-index: 1; }

  /* ==================================================
     PAGE HEADER
     Used on Projects, Humanitarian, Published, Contact.
     ================================================== */
  .page-head {
    padding-top: clamp(8rem, 20vh, 14rem);
    padding-bottom: var(--section-tight);
    max-width: var(--content-max);
    margin-inline: auto;
    display: flex;
    flex-direction: column;
    gap: var(--s-3);
  }
  .page-head__kicker { margin: 0; }
  .page-head__title {
    font-size: clamp(3rem, 10vw, 7rem);
    line-height: 1;
    letter-spacing: var(--track-tight);
    margin-block: var(--s-2);
  }
  .page-head__body {
    color: var(--mid);
    font-size: 1.125rem;
    line-height: 1.55;
    max-width: 56ch;
  }
}