/* ============ Variables & Reset ============ */
    :root {
      --hue: 130;

      /* Dark mode accents — signal lime */
      --accent:   #D2FF00;
      --accent-2: oklch(0.92 0.22 110);
      --accent-3: oklch(0.86 0.20 130);

      /* Dark mode surfaces — warm-grey dark, lime-friendly */
      --bg:        #000000;
      --surface:   #14160F;
      --surface-2: #282C20;

      /* Dark mode text — warm off-whites tinted toward signal hue */
      --ink:   oklch(0.96 0.005 130);
      --ink-2: oklch(0.78 0.008 130);
      --ink-3: oklch(0.58 0.012 130);

      /* Dark mode rules — lime-tinted hairlines */
      --rule:   oklch(0.96 0.005 130 / 0.18);
      --rule-2: oklch(0.96 0.005 130 / 0.07);

      --f-sans: 'Inter', -apple-system, BlinkMacSystemFont, "SF Pro Display", sans-serif;
      --f-mono: 'JetBrains Mono', ui-monospace, monospace;

      --maxw: 1280px;
      --gutter: 48px;
    }

    html[data-mode="light"] {
      /* Light mode accents — deep warm-gray (lime is unreadable on white) */
      --accent:   oklch(0.42 0.03 130);
      --accent-2: oklch(0.50 0.04 130);
      --accent-3: oklch(0.36 0.04 130);

      /* Light mode surfaces */
      --bg:        oklch(0.985 0.005 130);
      --surface:   #ffffff;
      --surface-2: oklch(0.96 0.008 130);

      /* Light mode text */
      --ink:   oklch(0.18 0.04 130);
      --ink-2: oklch(0.36 0.03 130);
      --ink-3: oklch(0.52 0.02 130);

      /* Light mode rules */
      --rule:   oklch(0.40 0.04 130 / 0.30);
      --rule-2: oklch(0.18 0.03 130 / 0.10);
    }

    * {
      box-sizing: border-box;
    }

    html,
    body {
      margin: 0;
      padding: 0;
      overflow-x: hidden;
    }

    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: var(--f-sans);
      background: var(--bg);
      color: var(--ink);
      font-size: 16px;
      line-height: 1.55;
      -webkit-font-smoothing: antialiased;
      text-rendering: optimizeLegibility;
      letter-spacing: -0.01em;
      overflow-x: hidden;
      padding-top: 56px;
    }

    a {
      color: inherit;
    }

    button {
      font: inherit;
      color: inherit;
      background: none;
      border: 0;
      cursor: pointer;
    }

    ::selection {
      background: var(--accent);
      color: #000;
    }

    .wrap {
      max-width: var(--maxw);
      margin: 0 auto;
      padding: 0 var(--gutter);
    }

    .center {
      text-align: center;
    }


    /* ============ Trust bar (top strip — Apple community calendar listing) ============ */
    :root {
      --trust-bar-h: 36px;
    }

    .trust-bar {
      position: fixed;
      top: 0;
      left: 0;
      right: 0;
      z-index: 60;
      display: flex;
      align-items: center;
      justify-content: center;
      flex-wrap: wrap;
      gap: 10px;
      min-height: var(--trust-bar-h);
      padding: 6px 16px;
      background: color-mix(in srgb, var(--bg) 58%, transparent);
      backdrop-filter: saturate(180%) blur(20px);
      -webkit-backdrop-filter: saturate(180%) blur(20px);
      border-bottom: 1px solid var(--rule-2);
      text-decoration: none;
      transition: background 180ms cubic-bezier(0.22, 1, 0.36, 1);
    }
    .trust-bar:hover {
      background: color-mix(in srgb, var(--bg) 72%, transparent);
    }
    .trust-bar:focus-visible {
      outline: 2px solid var(--accent);
      outline-offset: -2px;
    }

    .trust-bar-mark {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      color: oklch(0.80 0.13 55);
      filter: drop-shadow(0 0 6px color-mix(in oklab, oklch(0.80 0.13 55) 50%, transparent));
      line-height: 0;
    }
    html[data-mode="light"] .trust-bar-mark {
      color: oklch(0.62 0.14 50);
      filter: none;
    }

    .trust-bar-label {
      font-family: 'Geist Mono', ui-monospace, 'SF Mono', monospace;
      font-size: 11px;
      font-weight: 500;
      letter-spacing: 0.18em;
      text-transform: uppercase;
      color: var(--ink);
      white-space: nowrap;
    }

    .trust-bar-sep {
      color: var(--ink-3);
      opacity: 0.5;
      padding: 0 2px;
    }

    .trust-bar-desc {
      font-family: 'Geist', 'PingFang TC', 'Noto Sans TC', system-ui, sans-serif;
      font-size: 12px;
      line-height: 1.4;
      color: var(--ink-2);
      font-feature-settings: 'palt' 1;
    }

    @media (max-width: 640px) {
      :root { --trust-bar-h: 32px; }
      .trust-bar {
        padding: 10px 12px;
        gap: 8px;
      }
      .trust-bar-label {
        font-size: 10.5px;
        letter-spacing: 0.12em;
      }
      .trust-bar-sep { display: none; }
      .trust-bar-desc { font-size: 11px; }
    }

    /* ============ Nav ============ */
    nav.top {
      position: fixed;
      top: var(--trust-bar-h, 36px);
      left: 0;
      right: 0;
      z-index: 50;
      background: color-mix(in srgb, var(--bg) 72%, transparent);
      backdrop-filter: saturate(180%) blur(20px);
      -webkit-backdrop-filter: saturate(180%) blur(20px);
      border-bottom: 1px solid var(--rule-2);
      display: block;
      width: 100%;
    }

    nav.top .row {
      display: grid !important;
      grid-template-columns: 1fr auto 1fr;
      align-items: center;
      height: 52px;
      font-size: 13px;
    }

    nav.top .brand {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 500;
      justify-self: start;
    }

    /* Logo switching by mode */
    .nav-logo { height: 28px; width: auto; }
    .nav-logo--dark  { display: none; }
    .nav-logo--light { display: block; }
    html[data-mode="dark"] .nav-logo--light { display: none; }
    html[data-mode="dark"] .nav-logo--dark  { display: block; }

    /* Footer logo — inverted (footer bg is always dark) */
    .footer-logo { width: auto; }
    .footer-logo--dark  { display: none; }
    .footer-logo--light { display: block; }
    html[data-mode="dark"] .footer-logo--light { display: none; }
    html[data-mode="dark"] .footer-logo--dark  { display: block; }

    nav.top .brand .mark {
      width: 22px;
      height: 22px;
      border-radius: 6px;
      background: conic-gradient(from 180deg, var(--accent), var(--accent-2), var(--accent-3), var(--accent));
    }

    nav.top ul.nav-menu {
      list-style: none;
      padding: 0;
      margin: 0;
      display: flex;
      gap: 32px;
      color: var(--ink-3);
      justify-self: center;
    }

    nav.top ul.nav-menu a {
      text-decoration: none;
      transition: all .3s;
      font-weight: 500;
      position: relative;
    }

    nav.top ul.nav-menu a:hover {
      color: var(--accent);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      z-index: 101;
      background: none;
      border: none;
      padding: 0;
      margin: 0;
    }

    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--ink);
      border-radius: 6px;
      transition: all .3s cubic-bezier(0.34, 1.56, 0.64, 1);
    }

    .hamburger.active span:nth-child(1) {
      transform: rotate(45deg) translateY(7px);
    }

    .hamburger.active span:nth-child(2) {
      opacity: 0;
    }

    .hamburger.active span:nth-child(3) {
      transform: rotate(-45deg) translateY(-7px);
    }

    /* Mobile Menu Overlay */
    .mobile-menu {
      display: none;
      position: fixed;
      top: calc(var(--trust-bar-h, 36px) + 52px);
      left: 0;
      right: 0;
      bottom: 0;
      background: var(--bg);
      z-index: 99;
      overflow-y: auto;
      overflow-x: hidden;
      animation: slideDown .3s cubic-bezier(0.34, 1.56, 0.64, 1);
    }

    @keyframes slideDown {
      from {
        opacity: 0;
        transform: translateY(-20px);
      }

      to {
        opacity: 1;
        transform: translateY(0);
      }
    }

    .mobile-menu.active {
      display: block;
    }

    .mobile-menu ul {
      list-style: none;
      padding: 0;
      margin: 0;
      display: flex;
      flex-direction: column;
    }

    .mobile-menu ul li {
      border-bottom: 1px solid var(--rule-2);
    }

    .mobile-menu ul a {
      display: block;
      padding: 16px 28px;
      text-decoration: none;
      color: var(--ink);
      font-size: 16px;
      font-weight: 500;
      transition: all .2s;
    }

    .mobile-menu ul a:hover {
      background: var(--surface);
      color: var(--accent);
    }

    .mobile-menu-divider {
      height: 1px;
      background: var(--rule-2);
      margin: 16px 0;
    }

    .mobile-menu-controls {
      padding: 16px 20px;
    }

    .mobile-control-group {
      margin-bottom: 20px;
    }

    .mobile-control-group:last-child {
      margin-bottom: 0;
    }

    .control-label {
      display: block;
      font-family: var(--f-mono);
      font-size: 12px;
      font-weight: 600;
      color: var(--ink-3);
      text-transform: uppercase;
      letter-spacing: 0.1em;
      margin-bottom: 12px;
    }

    .mobile-mode-switch,
    .mobile-lang-switch {
      display: flex;
      gap: 8px;
      width: 100%;
    }

    .mobile-mode-switch button,
    .mobile-lang-switch button {
      flex: 1;
      min-width: 0;
      padding: 12px 8px;
      border: 1px solid var(--rule-2);
      border-radius: 6px;
      background: var(--surface);
      color: var(--ink-2);
      font-size: 14px;
      font-weight: 500;
      cursor: pointer;
      transition: all .3s;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
    }

    .mobile-mode-switch button:hover,
    .mobile-lang-switch button:hover {
      border-color: var(--rule);
      color: var(--ink);
    }

    .mobile-mode-switch button.active,
    .mobile-lang-switch button.active {
      background: var(--accent) !important;
      color: #000 !important;
      border-color: var(--accent) !important;
      font-weight: 600;
    }

    /* For lang switch, high contrast is better */
    .mobile-lang-switch button.active {
      background: var(--ink) !important;
      color: var(--bg) !important;
      border-color: var(--ink) !important;
    }

    .nav-actions {
      display: flex;
      align-items: center;
      gap: 12px;
      justify-self: end;
    }

    .nav-switch {
      display: inline-flex;
      background: var(--surface);
      border: 1px solid var(--rule);
      border-radius: 6px;
      padding: 3px;
      font-family: var(--f-mono);
      font-size: 11px;
      white-space: nowrap;
    }

    .nav-switch button {
      padding: 6px 9px;
      border-radius: 6px;
      color: var(--ink-2);
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }

    .nav-lang-switch button {
      padding-inline: 10px;
    }

    nav.top .nav-sponsor-cta {
      background: var(--ink);
      color: var(--bg);
      padding: 8px 14px;
      border-radius: 6px;
      font-weight: 500;
      white-space: nowrap;
      text-decoration: none;
    }


/* ============ Footer ============ */
    footer {
      background: var(--ink);
      color: var(--bg);
      padding: 100px 0 60px;
      position: relative;
    }

    footer a {
      color: var(--bg);
      text-decoration: none;
      transition: color .2s;
      opacity: 0.8;
    }

    footer a:hover {
      opacity: 1;
    }

    footer h4 {
      color: var(--bg) !important;
      font-weight: 600;
      opacity: 0.9;
    }

    footer .footer-tagline {
      color: var(--bg);
      opacity: 0.7;
    }

    footer .footer-bottom {
      border-top: 1px solid var(--rule-2);
      color: var(--bg);
      opacity: 0.5;
      padding-top: 32px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr 1fr;
      gap: 56px;
      margin-bottom: 64px;
    }

    .footer-lock {
      display: flex;
      align-items: center;
      gap: 16px;
      font-weight: 600;
      font-size: 16px;
    }

    .footer-lock .mark {
      width: 32px;
      height: 32px;
      border-radius: 6px;
      background: conic-gradient(from 180deg, var(--accent), var(--accent-2), var(--accent-3), var(--accent));
      flex-shrink: 0;
    }

    .footer-tagline {
      margin-top: 32px;
      font-size: 15px;
      color: var(--ink-2);
      width: 100%;
      max-width: none;
      line-height: 1.65;
    }


    footer ul {
      list-style: none;
      padding: 0;
      margin: 0;
      display: flex;
      flex-direction: column;
      gap: 12px;
      font-size: 15px;
    }

    footer ul a {
      text-decoration: none;
      color: var(--bg);
      transition: all .3s;
      opacity: 0.75;
    }

    footer ul a:hover {
      opacity: 1;
      color: var(--bg);
    }

    .footer-bottom {
      display: flex;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 20px;
      padding-top: 48px;
      border-top: 1px solid var(--rule-2);
      font-family: var(--f-mono);
      font-size: 12px;
      color: var(--bg);
      opacity: 0.5;
      letter-spacing: 0.06em;
    }


    /* ============ iOS HIG Preview Layer ============ */
    :root {
      --ios-blue: #D2FF00;
      --ios-pink: #ff2d55;
      --ios-green: #34c759;
      --ios-yellow: #ffcc00;
      --ios-grouped-bg: #f2f2f7;
      --ios-grouped-bg-dark: #000000;
      --ios-card: #ffffff;
      --ios-card-dark: #1c1c1e;
      --ios-label: #000000;
      --ios-label-dark: #ffffff;
      --ios-secondary-label: rgba(60, 60, 67, 0.60);
      --ios-secondary-label-dark: rgba(235, 235, 245, 0.60);
      --ios-tertiary-label: rgba(60, 60, 67, 0.30);
      --ios-tertiary-label-dark: rgba(235, 235, 245, 0.30);
      --ios-separator: rgba(60, 60, 67, 0.29);
      --ios-separator-dark: rgba(84, 84, 88, 0.65);
      --ios-fill: rgba(120, 120, 128, 0.20);
      --ios-fill-dark: rgba(120, 120, 128, 0.36);
      --ios-selected: rgba(210, 255, 0, 0.14);
      --ios-radius: 6px;
      --ios-control-radius: 6px;
      --ios-shadow: 0 8px 24px rgba(0, 0, 0, 0.10);
      --ios-space-2: 8px;
      --ios-space-3: 12px;
      --ios-space-4: 16px;
      --ios-space-5: 20px;
      --ios-space-6: 24px;
      --ios-space-8: 32px;
      --ios-space-12: 48px;
      --ios-space-16: 64px;
    }

    body {
      font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Helvetica Neue", Arial, sans-serif;
      background: var(--ios-grouped-bg);
      letter-spacing: 0;
    }

    html[data-mode="dark"] body {
      background: var(--ios-grouped-bg-dark);
    }

    nav.top {
      background: rgba(248, 248, 248, 0.72);
      border-bottom-color: var(--ios-separator);
      backdrop-filter: saturate(180%) blur(24px);
      -webkit-backdrop-filter: saturate(180%) blur(24px);
    }

    html[data-mode="dark"] nav.top {
      background: rgba(18, 18, 18, 0.72);
      border-bottom-color: var(--ios-separator-dark);
    }

    nav.top .row {
      min-height: 56px;
    }

    .nav-switch {
      min-height: 34px;
      background: var(--ios-fill);
      border: 0;
      border-radius: 6px;
      padding: 2px;
      font-family: inherit;
      font-size: 12px;
      font-weight: 600;
    }

    .nav-switch button {
      min-width: 32px;
      min-height: 30px;
      border-radius: 6px;
      color: rgba(29, 29, 31, 0.72);
    }

    html[data-mode="light"] .nav-switch button {
      color: rgba(29, 29, 31, 0.72);
    }

    html[data-mode="dark"] .nav-switch button {
      color: var(--ios-secondary-label-dark);
    }

    .lang-switch button.active,
    .nav-switch button.active,
    .mobile-mode-switch button.active,
    .mobile-lang-switch button.active {
      background: rgba(255, 255, 255, 0.92) !important;
      color: #111113 !important;
      box-shadow: 0 1px 4px rgba(0, 0, 0, 0.18);
    }

    html[data-mode="light"] .lang-switch button.active,
    html[data-mode="light"] .nav-switch button.active,
    html[data-mode="light"] .mobile-mode-switch button.active,
    html[data-mode="light"] .mobile-lang-switch button.active {
      color: #111113 !important;
    }

    html[data-mode="dark"] .lang-switch button.active,
    html[data-mode="dark"] .nav-switch button.active,
    html[data-mode="dark"] .mobile-mode-switch button.active,
    html[data-mode="dark"] .mobile-lang-switch button.active {
      background: rgba(99, 99, 102, 0.72) !important;
      color: #fff !important;
    }

    nav.top .nav-sponsor-cta {
      min-height: 36px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      background: var(--ios-blue);
      color: #000;
      border-radius: 6px;
      padding: 8px 16px;
      font-weight: 700;
      box-shadow: 0 6px 16px rgba(210, 255, 0, 0.22);
    }
    html[data-mode="light"] nav.top .nav-sponsor-cta {
      background: var(--accent);
      color: #fff;
      box-shadow: 0 6px 16px rgba(0, 0, 0, 0.12);
    }

    .hamburger {
      width: 44px;
      height: 44px;
      align-items: center;
      justify-content: center;
      gap: 4px;
      border-radius: 50%;
      background: var(--ios-fill);
    }

    .hamburger span {
      width: 21px;
      height: 2px;
    }

    .mobile-menu {
      top: 56px;
      background: rgba(242, 242, 247, 0.94);
      backdrop-filter: saturate(180%) blur(24px);
      -webkit-backdrop-filter: saturate(180%) blur(24px);
    }

    html[data-mode="dark"] .mobile-menu {
      background: rgba(0, 0, 0, 0.9);
    }

    .mobile-menu ul {
      margin: 16px;
      overflow: hidden;
      border-radius: 6px;
      background: var(--ios-card);
    }

    html[data-mode="dark"] .mobile-menu ul {
      background: var(--ios-card-dark);
    }

    .mobile-menu ul li {
      border-bottom-color: var(--ios-separator);
    }

    html[data-mode="dark"] .mobile-menu ul li {
      border-bottom-color: var(--ios-separator-dark);
    }

    .mobile-menu ul a {
      min-height: 50px;
      padding: 14px 18px;
      font-size: 17px;
      color: var(--ios-label);
    }

    html[data-mode="dark"] .mobile-menu ul a {
      color: var(--ios-label-dark);
    }

    .hero {
      min-height: unset;
      padding: 58px 0 58px;
      background: #000;
      display: block;
      align-items: unset;
    }

    .photo-wall {
      opacity: 0.5;
      filter: saturate(0.92) contrast(1.02);
    }

    .photo-col img {
      border-radius: 6px;
      box-shadow: none;
    }

    .hero-overlay {
      background:
        linear-gradient(180deg, rgba(0, 0, 0, 0.38) 0%, rgba(0, 0, 0, 0.08) 38%, rgba(0, 0, 0, 0.72) 100%),
        rgba(0, 0, 0, 0.26);
    }

    h1.hero-title {
      max-width: none;
      line-height: 1.02;
      letter-spacing: 0;
    }

    h1.hero-title .hero-logo {
      margin-bottom: 0;
      filter: drop-shadow(0 8px 22px rgba(0, 0, 0, 0.28));
    }

    h1.hero-title .hero-date {
      margin-bottom: 0;
      font-family: inherit;
      font-size: 28px;
      font-weight: 700;
      letter-spacing: 0;
    }

    h1.hero-title .hero-tagline {
      font-weight: 800;
      letter-spacing: 0;
      background: linear-gradient(180deg, #ffffff 0%, rgba(255, 255, 255, 0.72) 100%);
      -webkit-background-clip: text;
      background-clip: text;
      text-shadow: 0 14px 48px rgba(0, 0, 0, 0.45);
    }

    .hero-cta-row {
      --hero-cta-width: min(100%, 380px);
      gap: 12px;
      margin-top: 28px;
    }

    .hero-cta-row > .hero-cta-glow-wrap,
    .hero-cta-row > .hero-sponsor-btn {
      width: var(--hero-cta-width);
    }

    .btn-primary,
    .submit-card-cta {
      min-height: 50px;
      border-radius: 6px;
      font-size: 17px;
      font-weight: 700;
      letter-spacing: 0;
      transition: transform .18s ease, opacity .18s ease, box-shadow .18s ease;
    }

    .hero-cta-btn {
      background: rgba(255, 255, 255, 0.92);
      color: #111;
      box-shadow: var(--ios-shadow);
      animation: ctaBreathe 3s ease-in-out infinite;
    }

    .hero-cta-glow-wrap::before {
      inset: -7px;
      opacity: 0.78;
      filter: blur(16px);
      animation: glowSpin 4s linear infinite, glowPulse 2.5s ease-in-out infinite;
    }

    .hero-sponsor-btn {
      background: var(--ios-blue);
      color: #000;
      box-shadow: 0 10px 28px rgba(210, 255, 0, 0.34);
    }

    .hero-cta-btn:hover,
    .hero-sponsor-btn:hover {
      transform: translateY(-2px);
    }

    .flip-clock {
      gap: 7px;
      padding-top: 18px;
    }

    .fc-card {
      width: 64px;
      height: 72px;
      border-radius: 6px;
      background: rgba(44, 44, 46, 0.74);
      border: 1px solid rgba(255, 255, 255, 0.12);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
    }

    .fc-num {
      color: #fff;
      font-size: 42px;
      letter-spacing: 0;
    }

    .fc-label {
      color: rgba(235, 235, 245, 0.74);
      font-family: inherit;
      font-size: 10px;
      font-weight: 700;
      letter-spacing: 0.08em;
    }

    html[data-mode="light"] .fc-label {
      color: #ffffff;
    }

    section {
      background: var(--ios-grouped-bg);
      border-top: 0;
    }

    html[data-mode="dark"] section {
      background: var(--ios-grouped-bg-dark);
    }

    .sec-eyebrow,
    .submit-col-label,
    .h-date {
      font-family: inherit;
      color: var(--ios-blue);
      letter-spacing: 0;
      text-transform: none;
    }

    .striped-title {
      font-size: 36px;
      letter-spacing: 0;
      line-height: 1.06;
    }

    .sec-desc {
      color: var(--ios-secondary-label);
      font-size: 19px;
      line-height: 1.55;
    }

    html[data-mode="dark"] .sec-desc {
      color: var(--ios-secondary-label-dark);
    }

    .hl,
    .news-card,
    .venue-card,
    .ticket,
    .submit-card,
    .h-card,
    .construction,
    .register-hero {
      background: var(--ios-card);
      border: 1px solid var(--ios-separator);
      border-radius: 6px;
      box-shadow: var(--ios-shadow);
      backdrop-filter: saturate(180%) blur(22px);
      -webkit-backdrop-filter: saturate(180%) blur(22px);
    }

    html[data-mode="dark"] .hl,
    html[data-mode="dark"] .news-card,
    html[data-mode="dark"] .venue-card,
    html[data-mode="dark"] .ticket,
    html[data-mode="dark"] .submit-card,
    html[data-mode="dark"] .h-card,
    html[data-mode="dark"] .construction,
    html[data-mode="dark"] .register-hero {
      background: var(--ios-card-dark);
      border-color: var(--ios-separator-dark);
    }

    .hl:hover,
    .h-item:hover .h-card {
      transform: translateY(-3px);
      box-shadow: 0 16px 38px rgba(0, 0, 0, 0.16);
    }

    .topic-pill {
      background: var(--ios-fill);
      border: 0;
      border-radius: 6px;
      font-family: inherit;
      color: var(--ios-secondary-label);
    }

    html[data-mode="dark"] .topic-pill {
      color: var(--ios-secondary-label-dark);
    }

    .submit-card-cta {
      background: var(--ios-blue);
      color: #000;
      box-shadow: 0 10px 24px rgba(210, 255, 0, 0.26);
    }
    html[data-mode="light"] .submit-card-cta {
      background: var(--accent);
      color: #fff;
      box-shadow: 0 10px 24px rgba(0, 0, 0, 0.12);
    }

    @media (prefers-reduced-motion: reduce) {
      *,
      *::before,
      *::after {
        animation-duration: 0.001ms !important;
        animation-iteration-count: 1 !important;
        scroll-behavior: auto !important;
        transition-duration: 0.001ms !important;
      }
    }

    @media (max-width: 640px) {
      .submit-card {
        padding: 24px;
      }

      .submit-card-info {
        grid-template-columns: 1fr;
        gap: 24px;
      }
    }

    /* ============ Construction Placeholder ============ */
    .construction {
      margin-top: 60px;
      padding: 80px 40px;
      background: var(--surface-2);
      border: 1px dashed var(--rule);
      border-radius: 6px;
      text-align: center;
      position: relative;
    }

    .map-btn {
      position: absolute;
      bottom: 16px;
      left: 16px;
      z-index: 5;
      background: rgba(255, 255, 255, 0.9);
      backdrop-filter: blur(8px);
      -webkit-backdrop-filter: blur(8px);
      border: 1px solid rgba(0, 0, 0, 0.1);
      color: #1d1d1f;
      padding: 10px 16px;
      border-radius: 6px;
      font-size: 14px;
      font-weight: 600;
      text-decoration: none;
      display: flex;
      align-items: center;
      gap: 8px;
      box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
      transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
      cursor: pointer;
    }

    .map-btn:hover {
      background: #fff;
      transform: translateY(-2px);
      box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
    }

    html[data-mode="dark"] .map-btn {
      background: rgba(45, 45, 47, 0.9);
      color: #f5f5f7;
      border-color: rgba(255, 255, 255, 0.1);
    }

    .map-btn.active {
      background: var(--accent);
      color: var(--bg);
      border-color: var(--accent);
    }

    html[data-mode="dark"] .map-btn.active {
      background: var(--accent);
      color: var(--bg);
    }
    html[data-mode="light"] .map-btn.active {
      color: #fff;
    }

    .construction h3 {
      font-size: 24px;
      font-weight: 600;
      letter-spacing: -0.02em;
      margin: 0;
      background: linear-gradient(110deg, var(--accent), var(--accent-2));
      -webkit-background-clip: text;
      background-clip: text;
      color: transparent;
    }

    .construction p {
      margin-top: 12px;
      color: var(--ink-3);
      font-size: 14px;
      font-family: var(--f-mono);
      text-transform: uppercase;
      letter-spacing: 0.1em;
    }

    /* ============ Speaker Grid ============ */
    .speaker-grid {
      margin-top: 72px;
      display: grid;
      grid-template-columns: repeat(6, minmax(0, 1fr));
      gap: clamp(20px, 2.4vw, 32px);
      align-items: start;
    }

    @media (max-width: 1200px) {
      .speaker-grid {
        grid-template-columns: repeat(4, minmax(0, 1fr));
      }
    }

    @media (max-width: 820px) {
      .speaker-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
      }
    }

    .speaker-card {
      display: flex;
      flex-direction: column;
      gap: 14px;
      cursor: pointer;
      text-align: left;
      min-width: 0;
    }

    .speaker-photo {
      position: relative;
      width: 100% !important;
      max-width: 100% !important;
      min-width: 0 !important;
      aspect-ratio: 4 / 5;
      height: auto !important;
      overflow: hidden;
      padding: 2px;
      border-radius: 12px;
      background: conic-gradient(
        from var(--speaker-ring-angle, 0deg),
        #f59e0b, #ec4899, #8b5cf6, #D2FF00, #f59e0b
      );
      transition: transform .3s cubic-bezier(0.34, 1.56, 0.64, 1);
      animation: speakerRingSpin 4s linear infinite;
      isolation: isolate;
    }

    @property --speaker-ring-angle {
      syntax: "<angle>";
      initial-value: 0deg;
      inherits: false;
    }

    @keyframes speakerRingSpin {
      to { --speaker-ring-angle: 360deg; }
    }

    .speaker-photo::before {
      content: "";
      position: absolute;
      inset: -4px;
      border-radius: 14px;
      background: conic-gradient(
        from var(--speaker-ring-angle, 0deg),
        #f59e0b, #ec4899, #8b5cf6, #D2FF00, #f59e0b
      );
      filter: blur(10px);
      opacity: 0.6;
      z-index: -1;
      animation: speakerRingSpin 4s linear infinite;
    }

    .speaker-photo::after {
      content: "";
      position: absolute;
      inset: 2px;
      border-radius: 10px;
      background: linear-gradient(
        180deg,
        transparent 0%,
        transparent 60%,
        color-mix(in oklab, var(--bg) 80%, transparent) 100%
      );
      pointer-events: none;
    }

    .speaker-photo img {
      width: 100% !important;
      height: 100% !important;
      border-radius: 10px;
      object-fit: cover !important;
      object-position: center center;
      display: block;
      background: var(--surface);
      filter: saturate(0.78) contrast(1.05);
      transition: filter var(--t-mid) var(--ease-out);
    }

    .speaker-card:hover .speaker-photo {
      transform: translateY(-4px);
    }
    .speaker-card:hover .speaker-photo::before {
      opacity: 0.9;
      filter: blur(14px);
    }
    .speaker-card:hover .speaker-photo img {
      filter: saturate(1.0) contrast(1.0);
    }

    body.is-modal-open .speaker-photo,
    body.is-modal-open .speaker-photo::before {
      animation-play-state: paused;
    }
    body.is-modal-open .speaker-card:hover .speaker-photo {
      transform: none;
    }
    body.is-modal-open .speaker-card:hover .speaker-photo::before {
      opacity: 0.6;
      filter: blur(10px);
    }

    /* Placeholder — flat dark surface, keeps the rainbow ring + halo around it */
    .speaker-photo-placeholder {
      width: 100%;
      height: 100%;
      border-radius: 10px;
      background: var(--surface);
      position: relative;
      display: grid;
      place-items: center;
      overflow: hidden;
    }
    .speaker-photo-placeholder::before {
      content: "";
      width: 38%;
      aspect-ratio: 1;
      background: #d2ff00;
      opacity: 0.95;
      mask: url("../img/svg/swift.svg") center / contain no-repeat;
      -webkit-mask: url("../img/svg/swift.svg") center / contain no-repeat;
      filter: drop-shadow(0 0 18px color-mix(in oklab, #d2ff00 38%, transparent));
    }
    .speaker-photo-placeholder::after {
      content: "";
      position: absolute;
      inset: 18%;
      border-radius: 999px;
      background: color-mix(in oklab, #d2ff00 10%, transparent);
      filter: blur(28px);
      z-index: -1;
    }
    .speaker-card--placeholder .speaker-photo::after {
      opacity: 0.35;
    }

    .speaker-card-meta {
      display: flex;
      flex-direction: column;
      gap: 4px;
    }

    .speaker-name {
      margin: 0;
      font-family: var(--f-display);
      font-size: 14px;
      color: var(--ink);
      letter-spacing: -0.02em;
      text-transform: uppercase;
      line-height: 1.2;
    }

    .speaker-role {
      margin: 0;
      font-family: var(--f-mono);
      font-size: 11px;
      color: var(--ink-3);
      letter-spacing: 0.08em;
      text-transform: uppercase;
    }

    /* ============ Staff Grid ============ */
    .staff-grid {
      margin-top: 72px;
      display: grid;
      grid-template-columns: repeat(6, 1fr);
      gap: 40px 24px;
      justify-items: center;
    }

    .staff-card {
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 14px;
      text-align: center;
    }

    .staff-avatar-wrap {
      position: relative;
      width: 120px;
      height: 120px;
      border-radius: 50%;
      padding: 5px;
      background: var(--accent);
      box-shadow: 0 4px 20px rgba(210, 255, 0, 0.35);
      transition: transform .3s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow .3s;
      animation: none;
    }
    html[data-mode="light"] .staff-avatar-wrap {
      box-shadow: 0 4px 20px rgba(0, 0, 0, 0.18);
    }

    .staff-avatar-wrap:hover {
      transform: translateY(-6px) scale(1.05);
      box-shadow: 0 12px 32px rgba(0, 0, 0, 0.22);
    }

    .staff-avatar-inner {
      width: 100%;
      height: 100%;
      border-radius: 50%;
      overflow: hidden;
      background: var(--surface);
      outline: 3px solid var(--bg);
    }

    .staff-avatar-inner img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
    }

    .staff-card-link {
      display: block;
      border-radius: 50%;
      text-decoration: none;
      transition: opacity .2s;
    }

    .staff-card-link:hover {
      opacity: 0.88;
    }

    .staff-name {
      font-size: 15px;
      font-weight: 600;
      color: var(--ink);
      letter-spacing: -0.01em;
      margin: 0;
    }

    .staff-role {
      font-size: 12px;
      font-family: var(--f-mono);
      color: var(--ink-3);
      letter-spacing: 0.06em;
      text-transform: uppercase;
      margin: 0;
    }

    @media (max-width: 980px) {

      nav.top .row {
        display: flex !important;
        justify-content: flex-end;
        position: relative;
      }

      nav.top .brand {
        position: absolute;
        left: 50%;
        transform: translateX(-50%);
        justify-self: auto;
      }

      nav.top ul.nav-menu {
        display: none !important;
      }

      .hamburger {
        display: flex !important;
      }

      nav.top .row>div:last-child {
        display: none !important;
      }

      .highlights {
        grid-template-columns: 1fr;
      }

      .staff-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 32px 16px;
      }

      .agenda-row {
        grid-template-columns: 80px 1fr;
        gap: 20px;
        padding: 24px 16px;
      }

      .agenda-row .speaker,
      .agenda-row .arrow {
        display: none;
      }

      .speakers {
        grid-template-columns: 1fr 1fr;
      }

      .venue-card {
        grid-template-columns: 1fr;
      }

      .venue-map {
        min-height: 300px;
      }

      .venue-body {
        padding: 32px;
      }

      .register-hero {
        padding: 48px 24px;
      }

      .tickets {
        grid-template-columns: 1fr;
      }

      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }

      .footer-grid>div:first-child {
        grid-column: 1 / -1;
      }

      .countdown-cell {
        padding: 0 18px;
      }

      .countdown-cell .num {
        font-size: 40px;
      }

      .hero {
        padding: 40px 0 40px;
      }

      h1.hero-title .gradient:first-child {
        margin-bottom: 20px;
      }
    }

    @media (max-width: 480px) {
      h1.hero-title .gradient:first-child {
        margin-bottom: 12px;
      }

      .hero {
        padding: 40px 0 40px;
      }

      .staff-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 28px 12px;
      }

      .staff-avatar-wrap {
        width: 96px;
        height: 96px;
      }
    }

    /* iOS HIG preview final overrides */
    .construction {
      background: var(--ios-card);
      border: 1px solid var(--ios-separator);
      border-radius: 6px;
      box-shadow: var(--ios-shadow);
      backdrop-filter: saturate(180%) blur(22px);
      -webkit-backdrop-filter: saturate(180%) blur(22px);
    }

    html[data-mode="dark"] .construction {
      background: var(--ios-card-dark);
      border-color: var(--ios-separator-dark);
    }

    @media (max-width: 980px) {
      .hero {
        min-height: unset;
        padding: 40px 0 40px;
      }
    }

    @media (max-width: 520px) {
      .hero-cta-row {
        --hero-cta-width: min(100%, 340px);
      }

      .flip-clock {
        width: min(100%, 340px);
      }

      .fc-card {
        width: 58px;
        height: 70px;
        border-radius: 6px;
      }

      .fc-num {
        font-size: 38px;
      }
    }

    @media (max-width: 480px) {
      .wrap {
        padding-inline: 22px;
      }

      h1.hero-title .hero-tagline {
        font-size: 0.546em;
      }
    }

    html[data-mode="light"] .nav-switch button,
    html[data-mode="light"] .mobile-mode-switch button,
    html[data-mode="light"] .mobile-lang-switch button {
      color: rgba(29, 29, 31, 0.78) !important;
    }

    html[data-mode="light"] .nav-switch button svg,
    html[data-mode="light"] .mobile-mode-switch button svg {
      stroke: currentColor;
      opacity: 1;
    }

    html[data-mode="light"] .nav-switch button.active,
    html[data-mode="light"] .mobile-mode-switch button.active,
    html[data-mode="light"] .mobile-lang-switch button.active {
      color: #111113 !important;
      background: rgba(255, 255, 255, 0.96) !important;
      box-shadow: 0 2px 8px rgba(0, 0, 0, 0.18);
    }

    html[data-mode="dark"] .striped-title {
      background: none !important;
      -webkit-background-clip: border-box !important;
      background-clip: border-box !important;
      -webkit-text-fill-color: #f0f0f0 !important;
      color: #f0f0f0 !important;
    }

    html[data-mode="light"] .striped-title {
      background: none !important;
      -webkit-background-clip: border-box !important;
      background-clip: border-box !important;
      -webkit-text-fill-color: #1d1d1f !important;
      color: #1d1d1f !important;
    }

    .news-side-title .label-heading,
    .news-side-title .label-heading .gradient,
    .news-side-title .label-heading .thin {
      background: none !important;
      -webkit-background-clip: border-box !important;
      background-clip: border-box !important;
      -webkit-text-fill-color: var(--ink) !important;
      color: var(--ink) !important;
    }

    html[data-mode="light"] .news-side-title .label-heading,
    html[data-mode="light"] .news-side-title .label-heading .gradient,
    html[data-mode="light"] .news-side-title .label-heading .thin {
      -webkit-text-fill-color: #111113 !important;
      color: #111113 !important;
    }

    html[data-mode="dark"] .news-side-title .label-heading,
    html[data-mode="dark"] .news-side-title .label-heading .gradient,
    html[data-mode="dark"] .news-side-title .label-heading .thin {
      -webkit-text-fill-color: #ffffff !important;
      color: #ffffff !important;
    }

    /* iOS HIG-like spacing scale */
    section {
      padding: var(--ios-space-16) 0;
    }

    .sec-desc {
      margin-top: var(--ios-space-6);
    }

    .hero-cta-row {
      gap: var(--ios-space-3);
      margin-top: var(--ios-space-6);
    }

    .highlights,
    .speakers,
    .tickets,
    .topic-tags-wrap,
    .h-timeline {
      margin-top: var(--ios-space-12);
    }

    .highlights,
    .speakers,
    .tickets {
      gap: var(--ios-space-4);
    }

    .topic-tags-wrap {
      gap: var(--ios-space-2);
    }

    .hl,
    .submit-card,
    .register-hero {
      padding: var(--ios-space-6);
    }

    .news-side-title,
    .news-wrap,
    .venue-body {
      padding: var(--ios-space-6);
    }

    .submit-card-info {
      gap: var(--ios-space-6);
      margin-bottom: var(--ios-space-6);
    }

    .striped-header-wrap {
      gap: var(--ios-space-8);
      margin-bottom: var(--ios-space-12);
    }

    .construction {
      margin-top: var(--ios-space-12);
      padding: var(--ios-space-16) var(--ios-space-6);
    }

    .news-row {
      margin-bottom: var(--ios-space-3);
    }

    .news-row-header {
      padding: var(--ios-space-4) var(--ios-space-5);
    }

    @media (max-width: 980px) {
      section {
        padding: var(--ios-space-12) 0;
      }

      .venue-body,
      .register-hero {
        padding: var(--ios-space-6);
      }
    }

    @media (max-width: 640px) {
      :root {
        --gutter: 20px;
      }

      section {
        padding: var(--ios-space-12) 0;
      }

      .highlights,
      .speakers,
      .tickets,
      .topic-tags-wrap,
      .h-timeline,
      .construction {
        margin-top: var(--ios-space-8);
      }

      .hl,
      .submit-card,
      .news-side-title,
      .news-wrap,
      .venue-body,
      .register-hero {
        padding: var(--ios-space-5);
      }

      .highlights,
      .speakers,
      .tickets {
        gap: var(--ios-space-3);
      }
    }

    @media (max-width: 480px) {
      .wrap {
        padding-inline: 20px;
      }
    }