:root {
  --ink: #172033;
  --muted: #667085;
  --line: #d9e1ec;
  --paper: #ffffff;
  --soft: #f5f8fb;
  --navy: #0f3d68;
  --blue: #1967a3;
  --cyan: #23a6c2;
  --green: #0f8a75;
  --amber: #d89b28;
  --shadow: 0 20px 60px rgba(23, 32, 51, 0.14);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  font-family: "Inter", Arial, sans-serif;
  background: var(--paper);
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  display: block;
  max-width: 100%;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 72px;
  padding: 0 5vw;
  background: rgba(255, 255, 255, 0.94);
  border-bottom: 1px solid rgba(217, 225, 236, 0.8);
  backdrop-filter: blur(14px);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--navy);
  min-width: 250px;
}

.brand-mark {
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  color: #fff;
  font-weight: 800;
  background: linear-gradient(135deg, var(--navy), var(--cyan));
  border-radius: 8px;
}

.brand strong,
.brand small {
  display: block;
  line-height: 1.15;
}

.brand small {
  margin-top: 2px;
  color: var(--muted);
  font-size: 12px;
  max-width: 420px;
  white-space: normal;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: clamp(10px, 1.35vw, 22px);
  color: #344054;
  font-size: 13px;
  font-weight: 700;
}

.site-nav a {
  position: relative;
  padding: 26px 0;
}

.site-nav a::after {
  position: absolute;
  right: 0;
  bottom: 18px;
  left: 0;
  height: 3px;
  background: var(--amber);
  border-radius: 99px;
  content: "";
  opacity: 0;
  transform: scaleX(0.25);
  transition: 180ms ease;
}

.site-nav a:hover::after,
.site-nav a.active::after {
  opacity: 1;
  transform: scaleX(1);
}

.site-nav a.active {
  color: var(--navy);
}

.menu-button {
  display: none;
  width: 42px;
  height: 42px;
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.menu-button span {
  display: block;
  height: 2px;
  margin: 5px 0;
  background: var(--navy);
}

.hero {
  position: relative;
  min-height: calc(100svh - 72px);
  display: grid;
  align-items: center;
  overflow: hidden;
  color: #fff;
}

.hero-media,
.hero-overlay {
  position: absolute;
  inset: 0;
}

.hero-media {
  background:
    linear-gradient(120deg, rgba(15, 61, 104, 0.72), rgba(15, 138, 117, 0.34)),
    url("https://fhk.ais.cn/cms/website/functional/pic/202509/303250910170848971.jpg") center / cover;
  transform: scale(1.02);
}

.hero-media::after {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 74% 28%, rgba(35, 166, 194, 0.36), transparent 28%),
    linear-gradient(90deg, rgba(8, 27, 52, 0.92), rgba(8, 27, 52, 0.28) 68%);
  content: "";
}

.hero-overlay {
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.09) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.09) 1px, transparent 1px);
  background-size: 52px 52px;
  mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.7), transparent);
}

.hero-content {
  position: relative;
  z-index: 2;
  width: min(1100px, 90vw);
  margin: 0 auto;
  padding: 86px 0 150px;
}

.eyebrow,
.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--amber);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.eyebrow::before,
.section-kicker::before {
  width: 28px;
  height: 2px;
  background: currentColor;
  content: "";
}

.hero h1 {
  margin: 18px 0 16px;
  font-family: "Source Serif 4", Georgia, serif;
  font-size: clamp(64px, 12vw, 152px);
  line-height: 0.88;
}

.hero-copy {
  max-width: 680px;
  margin: 0;
  color: rgba(255, 255, 255, 0.9);
  font-size: clamp(22px, 3vw, 38px);
  font-weight: 700;
  line-height: 1.28;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 34px;
}

.button {
  display: inline-flex;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  padding: 0 20px;
  border-radius: 8px;
  font-weight: 800;
}

.button.primary {
  color: #fff;
  background: var(--amber);
}

.button.secondary {
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.55);
}

.hero-facts {
  position: absolute;
  right: 5vw;
  bottom: 34px;
  left: 5vw;
  z-index: 2;
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 1px;
  width: min(780px, 90vw);
  background: rgba(255, 255, 255, 0.2);
  border: 1px solid rgba(255, 255, 255, 0.26);
  backdrop-filter: blur(12px);
}

.hero-facts div {
  padding: 20px;
  background: rgba(7, 30, 55, 0.36);
}

.hero-facts span,
.hero-facts strong {
  display: block;
}

.hero-facts span {
  color: rgba(255, 255, 255, 0.72);
  font-size: 12px;
  text-transform: uppercase;
}

.hero-facts strong {
  margin-top: 6px;
  font-size: 18px;
}

.countdown-band {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: 30px;
  align-items: center;
  padding: 36px 5vw;
  background: var(--navy);
  color: #fff;
}

.countdown-heading h2,
.section-heading h2,
.contact-content h2,
.contact-content h1,
.content-panel h2 {
  margin: 10px 0 0;
  font-family: "Source Serif 4", Georgia, serif;
  font-size: clamp(34px, 4vw, 58px);
  line-height: 1.02;
}

.page-hero {
  position: relative;
  display: grid;
  min-height: 340px;
  align-items: end;
  padding: 96px 5vw 62px;
  color: #fff;
  overflow: hidden;
  background:
    linear-gradient(105deg, rgba(8, 27, 52, 0.92), rgba(15, 61, 104, 0.78), rgba(15, 138, 117, 0.38)),
    url("https://fhk.ais.cn/cms/website/functional/pic/202509/303250910170848971.jpg") center / cover;
}

.page-hero::after {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.1) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.1) 1px, transparent 1px);
  background-size: 52px 52px;
  content: "";
  opacity: 0.42;
}

.page-hero div {
  position: relative;
  z-index: 1;
  width: min(1040px, 100%);
  margin: 0 auto;
}

.page-hero h1 {
  margin: 12px 0;
  font-family: "Source Serif 4", Georgia, serif;
  font-size: clamp(50px, 8vw, 92px);
  line-height: 0.98;
}

.page-hero p {
  max-width: 760px;
  margin: 0;
  color: rgba(255, 255, 255, 0.82);
  font-size: 18px;
  line-height: 1.7;
}

.countdown-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
}

.countdown-grid div {
  min-height: 116px;
  padding: 22px 18px;
  text-align: center;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 8px;
}

.countdown-grid strong,
.countdown-grid span {
  display: block;
}

.countdown-grid strong {
  font-size: clamp(30px, 4vw, 54px);
  line-height: 1;
}

.countdown-grid span {
  margin-top: 10px;
  color: rgba(255, 255, 255, 0.72);
  font-size: 12px;
  font-weight: 800;
  text-transform: uppercase;
}

.section {
  padding: clamp(70px, 9vw, 120px) 5vw;
}

.section-heading {
  width: min(1040px, 100%);
  margin: 0 auto 34px;
}

.section-heading p {
  max-width: 760px;
  color: var(--muted);
  font-size: 18px;
  line-height: 1.7;
}

.about-layout,
.publication-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(320px, 0.8fr);
  gap: 36px;
  width: min(1040px, 100%);
  margin: 0 auto;
}

.about-single,
.single-panel {
  grid-template-columns: 1fr;
}

.about-copy {
  display: grid;
  gap: 18px;
}

.about-copy p,
.publication-main p,
.ethics-card p,
.contact-content p,
.instruction-grid p {
  margin: 0;
  color: #475467;
  font-size: 16px;
  line-height: 1.78;
}

.venue-panel {
  overflow: hidden;
  align-self: start;
  background: var(--soft);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.venue-panel img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  background:
    linear-gradient(135deg, rgba(15, 61, 104, 0.9), rgba(15, 138, 117, 0.7)),
    repeating-linear-gradient(45deg, rgba(255, 255, 255, 0.14) 0 1px, transparent 1px 18px);
}

.venue-panel div {
  padding: 24px;
}

.venue-panel span,
.date-grid span,
.day-card span,
.contact-card span {
  color: var(--muted);
  font-size: 12px;
  font-weight: 800;
  text-transform: uppercase;
}

.venue-panel strong {
  display: block;
  margin-top: 8px;
  color: var(--navy);
  font-size: 24px;
}

.venue-panel p {
  margin: 6px 0 0;
  color: var(--muted);
}

.dates-section,
.committee-section {
  background: var(--soft);
}

.date-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 18px;
  width: min(1040px, 100%);
  margin: 0 auto;
}

.date-grid article,
.topic-grid article,
.committee-grid article,
.publication-main,
.ethics-card,
.day-card,
.instruction-grid article,
.contact-card,
.quick-link-grid a,
.content-panel,
.submit-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: 0 12px 35px rgba(23, 32, 51, 0.07);
}

.date-grid article {
  min-height: 150px;
  padding: 24px;
  border-top: 4px solid var(--green);
}

.date-grid strong {
  display: block;
  margin-top: 16px;
  color: var(--navy);
  font-size: 22px;
  line-height: 1.18;
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  width: min(1040px, 100%);
  margin: 0 auto;
}

.quick-links-section {
  background: #fff;
}

.quick-link-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
  width: min(1040px, 100%);
  margin: 0 auto;
}

.quick-link-grid a {
  position: relative;
  min-height: 210px;
  padding: 26px;
  overflow: hidden;
  transition: 180ms ease;
}

.quick-link-grid a:hover {
  transform: translateY(-4px);
  box-shadow: 0 18px 42px rgba(23, 32, 51, 0.12);
}

.quick-link-grid span {
  color: var(--amber);
  font-family: "Source Serif 4", Georgia, serif;
  font-size: 36px;
  font-weight: 700;
}

.quick-link-grid strong {
  display: block;
  margin-top: 18px;
  color: var(--navy);
  font-size: 20px;
}

.quick-link-grid p {
  margin: 12px 0 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.6;
}

.topic-grid article {
  position: relative;
  overflow: hidden;
  min-height: 276px;
  padding: 28px;
}

.topic-grid article::before {
  position: absolute;
  inset: auto -30px -44px auto;
  width: 150px;
  height: 150px;
  background:
    radial-gradient(circle, rgba(35, 166, 194, 0.14) 0 24%, transparent 25% 100%),
    conic-gradient(from 0deg, rgba(15, 61, 104, 0.16), rgba(15, 138, 117, 0.14), rgba(216, 155, 40, 0.18), rgba(15, 61, 104, 0.16));
  border-radius: 50%;
  content: "";
}

.topic-grid span {
  color: var(--amber);
  font-family: "Source Serif 4", Georgia, serif;
  font-size: 42px;
  font-weight: 700;
}

.topic-grid h3,
.committee-grid h3,
.publication-layout h3,
.instruction-grid h3 {
  margin: 18px 0 12px;
  color: var(--navy);
  font-size: 20px;
  line-height: 1.25;
}

.topic-grid p,
.committee-grid p {
  margin: 0;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.62;
}

.committee-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  width: min(1040px, 100%);
  margin: 0 auto;
}

.committee-grid article {
  padding: 28px;
  border-left: 4px solid var(--cyan);
}

.committee-grid p + p {
  margin-top: 10px;
}

.publication-section {
  background:
    linear-gradient(90deg, rgba(15, 61, 104, 0.06), transparent 42%),
    #fff;
}

.publication-main,
.ethics-card {
  padding: 34px;
}

.publication-main {
  color: #fff;
  background:
    linear-gradient(135deg, rgba(15, 61, 104, 0.96), rgba(15, 138, 117, 0.86)),
    url("https://fhk.ais.cn/cms/website/editor/202508/303250829092745434.jpg") center / cover;
}

.publication-main h3,
.publication-main p {
  color: #fff;
}

.ethics-card {
  border-top: 4px solid var(--amber);
}

.program-section {
  background: var(--soft);
}

.program-layout {
  display: grid;
  grid-template-columns: minmax(220px, 0.8fr) minmax(320px, 1.4fr) minmax(220px, 0.8fr);
  gap: 20px;
  width: min(1040px, 100%);
  margin: 0 auto;
}

.day-card {
  padding: 26px;
}

.featured-day {
  border-top: 4px solid var(--amber);
}

.day-card h3 {
  margin: 8px 0 22px;
  color: var(--navy);
  font-size: 22px;
}

.agenda-row {
  display: grid;
  grid-template-columns: 110px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding: 12px 0;
  border-top: 1px solid var(--line);
}

.agenda-row time {
  color: var(--green);
  font-size: 13px;
  font-weight: 800;
}

.agenda-row strong {
  font-size: 14px;
  line-height: 1.4;
}

.instruction-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  width: min(1040px, 100%);
  margin: 22px auto 0;
}

.instruction-grid article {
  padding: 28px;
}

.content-panel {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(280px, 0.85fr);
  gap: 34px;
  width: min(1040px, 100%);
  margin: 0 auto;
  padding: 36px;
}

.number-list {
  display: grid;
  gap: 16px;
  margin: 28px 0 0;
  padding-left: 22px;
  color: #475467;
  font-size: 16px;
  line-height: 1.72;
}

.number-list li::marker {
  color: var(--green);
  font-weight: 800;
}

.submit-card {
  align-self: start;
  padding: 28px;
  background:
    linear-gradient(135deg, rgba(15, 61, 104, 0.06), rgba(15, 138, 117, 0.08)),
    #fff;
}

.submit-card strong {
  display: block;
  color: var(--navy);
  font-size: 28px;
}

.submit-card p {
  margin: 12px 0 24px;
  color: var(--muted);
  line-height: 1.65;
}

.text-link {
  display: inline-flex;
  margin-top: 18px;
  color: var(--blue);
  font-weight: 800;
  text-decoration: underline;
  text-underline-offset: 4px;
}

.contact-section {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(300px, 0.8fr);
  gap: 36px;
  align-items: center;
  padding: clamp(70px, 9vw, 110px) 5vw;
  color: #fff;
  background:
    linear-gradient(110deg, rgba(12, 47, 80, 0.96), rgba(15, 138, 117, 0.82)),
    url("https://fhk.ais.cn/cms/website/functional/pic/202509/303250910170755951.jpg") center / cover;
}

.full-contact {
  min-height: calc(100svh - 72px);
}

.contact-content {
  width: min(680px, 100%);
  margin-left: auto;
}

.contact-content p {
  color: rgba(255, 255, 255, 0.82);
}

.contact-content a {
  color: #fff;
  font-weight: 800;
  text-decoration: underline;
  text-underline-offset: 4px;
}

.contact-card {
  width: min(420px, 100%);
  padding: 30px;
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(12px);
}

.contact-card strong,
.contact-card span {
  display: block;
}

.contact-card strong {
  color: var(--navy);
  font-size: 30px;
}

.contact-card span {
  margin-top: 12px;
}

.contact-card .button {
  margin-top: 24px;
}

.site-footer {
  display: flex;
  flex-wrap: wrap;
  gap: 16px 26px;
  align-items: center;
  justify-content: center;
  padding: 26px 5vw;
  color: rgba(255, 255, 255, 0.76);
  background: #0b1f35;
  font-size: 13px;
  text-align: center;
}

.cmt-section {
  padding: 30px 5vw;
  color: #475467;
  background: #fff;
  border-top: 1px solid var(--line);
}

.cmt-section p {
  width: min(1040px, 100%);
  margin: 0 auto;
  font-size: 14px;
  line-height: 1.7;
}

.site-footer a {
  color: #fff;
}

@media (max-width: 980px) {
  .menu-button {
    display: block;
  }

  .site-nav {
    position: absolute;
    top: 72px;
    right: 0;
    left: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px 5vw 18px;
    background: #fff;
    border-bottom: 1px solid var(--line);
  }

  .site-nav.is-open {
    display: flex;
  }

  .site-nav a {
    padding: 16px 0;
  }

  .hero-facts,
  .countdown-band,
  .about-layout,
  .publication-layout,
  .contact-section {
    grid-template-columns: 1fr;
  }

  .date-grid,
  .topic-grid,
  .committee-grid,
  .program-layout,
  .instruction-grid,
  .quick-link-grid,
  .content-panel {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 680px) {
  .site-header {
    min-height: 66px;
  }

  .brand {
    min-width: 0;
  }

  .brand small {
    display: block;
    max-width: 220px;
    font-size: 11px;
  }

  .site-nav {
    top: 66px;
  }

  .hero {
    min-height: calc(100svh - 66px);
  }

  .hero-content {
    padding-top: 68px;
    padding-bottom: 210px;
  }

  .hero h1 {
    font-size: clamp(62px, 23vw, 96px);
  }

  .hero-copy {
    font-size: 22px;
  }

  .hero-facts,
  .countdown-grid,
  .date-grid,
  .topic-grid,
  .committee-grid,
  .program-layout,
  .instruction-grid,
  .quick-link-grid,
  .content-panel {
    grid-template-columns: 1fr;
  }

  .countdown-band {
    padding-top: 28px;
  }

  .agenda-row {
    grid-template-columns: 1fr;
    gap: 6px;
  }
}