:root {
  --ink: #182225;
  --muted: #59686d;
  --paper: #ffffff;
  --mist: #f1f6f6;
  --blue: #1f6d8b;
  --teal: #48a99a;
  --night: #171c1e;
  --line: #d7e2e2;
  --header-height: 64px;
  --content-width: 1120px;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 20px);
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 18px;
  line-height: 1.75;
  text-rendering: optimizeLegibility;
}

a { color: inherit; }

.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 100;
  padding: 10px 14px;
  color: #fff;
  background: var(--blue);
  transform: translateY(-150%);
}

.skip-link:focus { transform: translateY(0); }

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header-height);
  color: #fff;
  background: rgba(23, 28, 30, .98);
  border-bottom: 1px solid rgba(255, 255, 255, .1);
}

.header-inner {
  position: relative;
  width: min(var(--content-width), calc(100% - 48px));
  height: 100%;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: inline-flex;
  align-items: center;
  font-family: Arial, Helvetica, sans-serif;
  text-decoration: none;
}

.brand-copy { display: grid; line-height: 1.1; }
.brand-copy strong { font-size: 17px; letter-spacing: .02em; }
.brand-copy small { margin-top: 4px; color: #b9c5c7; font-size: 11px; letter-spacing: .08em; text-transform: uppercase; }

.primary-nav { display: flex; align-items: center; gap: 26px; font-family: Arial, Helvetica, sans-serif; }
.primary-nav a { color: #e8eeee; font-size: 13px; font-weight: 600; letter-spacing: .04em; text-decoration: none; }
.primary-nav a:hover, .primary-nav a:focus-visible { color: #83d6c8; }

.menu-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 10px 0 10px 12px;
  color: #fff;
  background: transparent;
  border: 0;
  font: 700 12px/1 Arial, Helvetica, sans-serif;
  letter-spacing: .08em;
  text-transform: uppercase;
  cursor: pointer;
}

.menu-icon {
  position: relative;
  display: block;
  width: 24px;
  height: 16px;
}

.menu-icon i {
  position: absolute;
  left: 0;
  width: 24px;
  height: 2px;
  background: currentColor;
  transition: transform .18s ease, top .18s ease;
}

.menu-icon i:first-child { top: 3px; }
.menu-icon i:last-child { top: 11px; }
.menu-toggle[aria-expanded="true"] .menu-icon i:first-child { top: 7px; transform: rotate(45deg); }
.menu-toggle[aria-expanded="true"] .menu-icon i:last-child { top: 7px; transform: rotate(-45deg); }

.hero {
  position: relative;
  min-height: 510px;
  display: grid;
  place-items: center;
  overflow: hidden;
  color: #fff;
  background: #243033 url("./assets/hero-melbourne.jpg") center 58% / cover no-repeat;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, rgba(9, 19, 21, .84), rgba(9, 19, 21, .55) 55%, rgba(9, 19, 21, .7));
}

.hero-content {
  position: relative;
  width: min(var(--content-width), calc(100% - 48px));
  padding: 74px 0 82px;
  text-align: center;
}

.hero-kicker {
  margin: 0 0 24px;
  color: #b9e7df;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .14em;
  text-transform: uppercase;
}

h1 {
  max-width: 1000px;
  margin: 0 auto;
  font-family: Arial, Helvetica, sans-serif;
  font-size: clamp(38px, 5.2vw, 68px);
  font-weight: 300;
  letter-spacing: -.035em;
  line-height: 1.05;
}

h1 span { font-weight: 600; }

.hero-meta {
  margin-top: 36px;
  font-family: Arial, Helvetica, sans-serif;
  font-size: clamp(18px, 2vw, 25px);
  line-height: 1.35;
}

.hero-meta p { margin: 5px 0; }
.hero-format { color: #d1dcde; font-size: 15px; letter-spacing: .025em; }

.content-shell { overflow: hidden; }

.section {
  width: min(var(--content-width), calc(100% - 48px));
  margin: 0 auto;
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr);
  gap: 34px;
  padding: 88px 0;
}

.section-tinted { position: relative; }
.section-tinted::before {
  position: absolute;
  inset: 0 50%;
  z-index: -1;
  width: 100vw;
  content: "";
  background: var(--mist);
  transform: translateX(-50%);
}

.section-index {
  margin: 12px 0 0;
  color: var(--teal);
  font-family: Arial, Helvetica, sans-serif;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .15em;
}

.section-body h2 {
  margin: 0 0 28px;
  color: var(--blue);
  font-family: Arial, Helvetica, sans-serif;
  font-size: clamp(34px, 4vw, 48px);
  font-weight: 300;
  letter-spacing: -.025em;
  line-height: 1.1;
}

.reading-width { max-width: 880px; }
.lead { margin-top: 0; color: #223034; font-size: 23px; line-height: 1.58; }
.section-body p { margin: 0 0 22px; }

.guiding-question {
  margin-top: 36px !important;
  padding-left: 24px;
  border-left: 3px solid var(--teal);
  color: #294247;
  font-size: 21px;
  font-style: italic;
}

.guiding-question span {
  display: block;
  margin-bottom: 4px;
  color: var(--blue);
  font-family: Arial, Helvetica, sans-serif;
  font-size: 12px;
  font-style: normal;
  font-weight: 800;
  letter-spacing: .13em;
  text-transform: uppercase;
}

.section-intro { max-width: 820px; color: var(--muted); }

.topic-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0 44px;
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
  counter-reset: topics;
}

.topic-list li {
  position: relative;
  padding: 22px 0 22px 48px;
  border-top: 1px solid var(--line);
  counter-increment: topics;
}

.topic-list li::before {
  position: absolute;
  top: 23px;
  left: 0;
  color: var(--blue);
  content: counter(topics, decimal-leading-zero);
  font-family: Arial, Helvetica, sans-serif;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: .08em;
}

.info-list {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  margin: 8px 0 34px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.info-list > div {
  min-width: 0;
  padding: 23px 20px 25px;
  border-right: 1px solid var(--line);
}

.info-list > div:first-child { padding-left: 0; }
.info-list > div:last-child { padding-right: 0; border-right: 0; }
.info-list dt {
  margin-bottom: 8px;
  color: var(--blue);
  font: 800 11px/1.2 Arial, Helvetica, sans-serif;
  letter-spacing: .13em;
  text-transform: uppercase;
}
.info-list dd { margin: 0; font-size: 16px; line-height: 1.45; }

.plain-note {
  max-width: 900px;
  margin-bottom: 0 !important;
  padding: 23px 26px;
  background: #eaf3f3;
  border-left: 4px solid var(--teal);
  color: #294247;
}

.speaker-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 30px;
  margin-top: 8px;
}

.speaker-card {
  min-width: 0;
  display: grid;
  grid-template-columns: minmax(170px, 42%) minmax(0, 1fr);
  overflow: hidden;
  background: var(--paper);
  border: 1px solid var(--line);
}

.speaker-photo {
  display: block;
  min-height: 100%;
  overflow: hidden;
  background: #dbe6e6;
}

.speaker-photo img {
  display: block;
  width: 100%;
  height: 100%;
  min-height: 340px;
  object-fit: cover;
  object-position: center;
  transition: transform .3s ease;
}

.speaker-photo:hover img { transform: scale(1.025); }
.speaker-copy { align-self: center; padding: 30px; }
.speaker-copy h3,
.organizer-card h3 {
  margin: 0;
  color: var(--ink);
  font-family: Arial, Helvetica, sans-serif;
  font-weight: 600;
  letter-spacing: -.02em;
  line-height: 1.15;
}
.speaker-copy h3 { font-size: 27px; }
.speaker-copy p { margin: 14px 0; font-size: 16px; line-height: 1.55; }
.speaker-copy .speaker-affiliation { color: var(--blue); font-weight: 700; }

.profile-link,
.email-link,
.photo-note a,
.footer-links a {
  color: var(--blue);
  text-decoration-color: rgba(31, 109, 139, .35);
  text-underline-offset: 4px;
}

.profile-link {
  font: 700 12px/1.3 Arial, Helvetica, sans-serif;
  letter-spacing: .04em;
}

.section-heading-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 24px;
}

.section-heading-row p {
  flex: none;
  color: var(--muted);
  font: 700 12px/1.4 Arial, Helvetica, sans-serif;
  letter-spacing: .09em;
  text-transform: uppercase;
}

.schedule-list {
  margin: 10px 0 0;
  padding: 0;
  border-top: 2px solid var(--ink);
  list-style: none;
}

.schedule-list li {
  display: grid;
  grid-template-columns: 200px minmax(0, 1fr);
  border-bottom: 1px solid var(--line);
}

.schedule-list time,
.schedule-list span { padding: 18px 20px; }
.schedule-list time {
  color: var(--blue);
  font: 700 14px/1.5 Arial, Helvetica, sans-serif;
  letter-spacing: .025em;
  border-right: 1px solid var(--line);
}
.schedule-list span { font-size: 17px; line-height: 1.5; }
.schedule-list .schedule-break { background: var(--mist); }

.organizer-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 48px 32px;
  margin-top: 34px;
}

.organizer-card {
  min-width: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

#organizers.section {
  width: min(1280px, calc(100% - 48px));
  grid-template-columns: 64px minmax(0, 1fr);
  gap: 32px;
}

.portrait-link {
  position: relative;
  display: block;
  width: min(100%, 264px);
  aspect-ratio: 4 / 5;
  margin: 0 auto 24px;
  overflow: hidden;
  background: #dbe6e6;
  border: 4px solid rgba(255, 255, 255, .92);
  border-radius: 50%;
  box-shadow: 0 12px 28px rgba(24, 34, 37, .12);
}

.portrait-link img {
  position: absolute;
  top: var(--portrait-top, 0);
  left: var(--portrait-left, 0);
  display: block;
  width: var(--portrait-width, 100%);
  max-width: none;
  height: var(--portrait-height, 100%);
  object-fit: cover;
  object-position: var(--portrait-position, center);
  transition: transform .3s ease;
}

.portrait-wang { --portrait-position: center 36%; }
.portrait-guo {
  --portrait-width: 112%;
  --portrait-height: 112%;
  --portrait-left: -6%;
  --portrait-top: -6%;
  --portrait-position: center 38%;
}
.portrait-li { --portrait-position: center 32%; }
.portrait-ding {
  --portrait-width: 100%;
  --portrait-height: 100%;
  --portrait-left: 0;
  --portrait-top: 0;
  --portrait-position: center;
}

.portrait-link:hover img { transform: scale(1.025); }
.organizer-card h3 { font-size: 21px; }
.organizer-card p {
  width: 100%;
  max-width: 276px;
  min-height: 4.5em;
  margin: 11px auto 13px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.5;
}
.photo-note { margin: 34px 0 0 !important; color: var(--muted); font-size: 13px; line-height: 1.55; }

.contact-section .section-body { padding: 4px 0 8px; }
.contact-name { margin-bottom: 2px !important; font-family: Arial, Helvetica, sans-serif; font-size: 25px; font-weight: 700; }
.contact-name + p { margin-bottom: 12px; color: var(--muted); }
.email-link { display: inline-block; font-family: Arial, Helvetica, sans-serif; font-weight: 700; }

.site-footer { color: #dbe4e5; background: var(--night); }
.footer-inner {
  width: min(var(--content-width), calc(100% - 48px));
  margin: 0 auto;
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 40px;
  padding: 42px 0 46px;
  font-family: Arial, Helvetica, sans-serif;
}
.footer-inner > div:first-child { display: grid; }
.footer-inner strong { color: #fff; font-size: 17px; }
.footer-inner span { margin-top: 5px; color: #93a3a6; font-size: 12px; }
.footer-links { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 12px 24px; }
.footer-links a { color: #b9e7df; font-size: 12px; }

:focus-visible { outline: 3px solid #ffd166; outline-offset: 4px; }

@media (max-width: 1080px) {
  .primary-nav { gap: 17px; }
  .primary-nav a { font-size: 12px; }
  .info-list { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .info-list > div { border-bottom: 1px solid var(--line); }
  .info-list > div:nth-child(3) { border-right: 0; }
  .info-list > div:nth-last-child(-n+2) { border-bottom: 0; }
  .speaker-card { grid-template-columns: minmax(150px, 39%) minmax(0, 1fr); }
  .speaker-copy { padding: 24px; }
  .organizer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 980px) {
  .menu-toggle { display: inline-flex; }
  .primary-nav {
    position: absolute;
    top: calc(100% + 1px);
    right: 0;
    width: min(340px, calc(100vw - 32px));
    max-height: calc(100vh - var(--header-height) - 20px);
    padding: 16px;
    display: grid;
    gap: 0;
    overflow: auto;
    visibility: hidden;
    background: rgba(23, 28, 30, .99);
    border: 1px solid rgba(255, 255, 255, .1);
    opacity: 0;
    pointer-events: none;
    transform: translateY(-8px);
    transition: opacity .16s ease, transform .16s ease, visibility .16s;
  }
  .primary-nav a { padding: 12px 10px; font-size: 14px; }
  .menu-open .primary-nav { visibility: visible; opacity: 1; pointer-events: auto; transform: translateY(0); }
  .speaker-grid { grid-template-columns: 1fr; }
  .speaker-card { grid-template-columns: minmax(220px, 36%) minmax(0, 1fr); }
  .organizer-grid { gap: 48px 28px; }
}

@media (max-width: 760px) {
  :root { --header-height: 58px; }
  body { font-size: 17px; line-height: 1.65; }
  .header-inner, .hero-content, .section { width: min(100% - 36px, var(--content-width)); }
  .brand-copy small { display: none; }
  .hero { min-height: 560px; background-position: 56% center; }
  .hero-content { padding: 70px 0; }
  .hero-kicker { font-size: 11px; line-height: 1.5; }
  h1 { font-size: clamp(37px, 11vw, 52px); }
  .section { grid-template-columns: 1fr; gap: 8px; padding: 68px 0; }
  .section-index { margin-top: 0; }
  .section-body h2 { margin-bottom: 22px; font-size: 35px; }
  .lead { font-size: 20px; }
  .topic-list { grid-template-columns: 1fr; gap: 0; }
  .info-list { grid-template-columns: 1fr; }
  .info-list > div,
  .info-list > div:first-child,
  .info-list > div:last-child {
    padding: 17px 0;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }
  .info-list > div:last-child { border-bottom: 0; }
  .speaker-card { grid-template-columns: 1fr; }
  .speaker-photo img { min-height: 0; aspect-ratio: 4 / 3; object-position: center 30%; }
  .speaker-copy { padding: 25px 22px 28px; }
  .section-heading-row { display: block; }
  .section-heading-row p { margin-top: -9px; }
  .schedule-list li { grid-template-columns: 1fr; padding: 15px 0; }
  .schedule-list time,
  .schedule-list span { padding: 0; border: 0; }
  .schedule-list span { margin-top: 4px; }
  .schedule-list .schedule-break { margin: 0 -18px; padding: 15px 18px; }
  #organizers.section {
    width: min(100% - 36px, var(--content-width));
    grid-template-columns: 1fr;
    gap: 8px;
  }
  .organizer-grid { grid-template-columns: 1fr; gap: 46px; }
  .organizer-card { width: 100%; max-width: 320px; margin: 0 auto; }
  .portrait-link { width: min(100%, 214px); }
  .organizer-card p { min-height: 0; }
  .footer-inner { width: min(100% - 36px, var(--content-width)); display: grid; gap: 22px; }
  .footer-links { display: grid; justify-content: start; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; }
}