:root {
  --navy: #003057;
  --ink: #14213d;
  --paper: #fafaf6;
  --white: #ffffff;
  --gold: #e9bf75;
  --gold-soft: #f4dbac;
  --cyan: #31d7ff;
  --rule: rgba(233, 191, 117, 0.36);
  --shadow: 0 28px 80px rgba(0, 0, 0, 0.38);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--paper);
  background:
    radial-gradient(circle at 75% 15%, rgba(49, 215, 255, 0.18), transparent 28rem),
    linear-gradient(135deg, #001429 0%, #003057 48%, #071225 100%);
  font-family:
    "Noto Sans SC", "Microsoft YaHei", "PingFang SC", Inter, Arial, sans-serif;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.22;
  background-image:
    linear-gradient(115deg, transparent 0 70%, rgba(244, 219, 172, 0.25) 70.2%, transparent 70.6%),
    linear-gradient(67deg, transparent 0 78%, rgba(49, 215, 255, 0.22) 78.2%, transparent 78.6%);
  background-size: 58px 58px, 72px 72px;
  mask-image: linear-gradient(90deg, transparent, black 35%, black 100%);
}

a {
  color: inherit;
}

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

.skip-link {
  position: absolute;
  left: 1rem;
  top: -4rem;
  z-index: 20;
  padding: 0.75rem 1rem;
  background: var(--paper);
  color: var(--ink);
}

.skip-link:focus {
  top: 1rem;
}

.shell {
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(0, 20, 41, 0.82);
  border-bottom: 1px solid rgba(233, 191, 117, 0.22);
  backdrop-filter: blur(18px);
}

.header-inner,
.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  min-height: 76px;
}

.brand img,
.footer-inner img {
  width: clamp(180px, 24vw, 310px);
  filter: brightness(0) invert(1);
}

.nav {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.nav a {
  padding: 0.7rem 0.9rem;
  text-decoration: none;
  color: rgba(250, 250, 246, 0.78);
  border: 1px solid transparent;
}

.nav a:hover,
.nav a:focus-visible {
  color: var(--gold-soft);
  border-color: var(--rule);
  outline: none;
}

.hero {
  padding: clamp(56px, 8vw, 104px) 0 72px;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(320px, 0.72fr);
  gap: clamp(32px, 6vw, 80px);
  align-items: center;
}

.eyebrow,
.section-kicker {
  margin: 0 0 1rem;
  color: var(--gold);
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 0.6rem;
  color: var(--gold-soft);
  font-size: clamp(3.1rem, 7.2vw, 6rem);
  line-height: 0.98;
  font-weight: 900;
}

h1 span {
  display: block;
}

.hero-subtitle {
  max-width: 16em;
  margin-bottom: 0.7rem;
  font-size: clamp(1.7rem, 4vw, 3.2rem);
  line-height: 1.18;
  font-weight: 850;
}

.hero-line {
  max-width: 36rem;
  color: rgba(250, 250, 246, 0.78);
  font-size: clamp(1rem, 1.6vw, 1.2rem);
  line-height: 1.75;
}

.event-meta {
  display: grid;
  gap: 0;
  max-width: 720px;
  margin: 2rem 0;
  border: 1px solid var(--rule);
}

.event-meta div {
  display: grid;
  grid-template-columns: 72px 1fr;
  gap: 1rem;
  align-items: baseline;
  padding: 1rem 1.1rem;
  border-bottom: 1px solid var(--rule);
}

.event-meta div:last-child {
  border-bottom: 0;
}

.event-meta span {
  color: var(--gold);
  font-weight: 800;
}

.event-meta strong {
  font-size: clamp(1.02rem, 2vw, 1.35rem);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  padding: 0.86rem 1.2rem;
  text-decoration: none;
  font-weight: 800;
  border: 1px solid var(--gold);
}

.button.primary {
  background: var(--gold);
  color: #091b32;
}

.button.secondary {
  background: transparent;
  color: var(--gold-soft);
}

.poster-panel {
  margin: 0;
  padding: 14px;
  background: rgba(250, 250, 246, 0.08);
  border: 1px solid rgba(244, 219, 172, 0.45);
  box-shadow: var(--shadow);
}

.poster-panel img {
  width: 100%;
  max-height: 78vh;
  object-fit: contain;
  background: #001429;
}

figcaption {
  padding-top: 0.8rem;
  color: rgba(250, 250, 246, 0.68);
  font-size: 0.9rem;
  text-align: center;
}

.section {
  padding: clamp(56px, 7vw, 90px) 0;
  border-top: 1px solid rgba(233, 191, 117, 0.18);
}

.intro-band {
  background: rgba(250, 250, 246, 0.95);
  color: var(--ink);
}

.intro-grid,
.speaker-grid,
.join-grid {
  display: grid;
  grid-template-columns: minmax(260px, 0.75fr) minmax(0, 1fr);
  gap: clamp(28px, 6vw, 72px);
  align-items: start;
}

.intro-grid h2,
.section-heading h2,
.speaker-grid h2,
.join-copy h2 {
  margin-bottom: 0;
  font-size: clamp(2rem, 4vw, 4rem);
  line-height: 1.12;
  font-weight: 900;
}

.intro-grid p:last-child,
.speaker-copy p,
.join-copy p {
  color: currentColor;
  font-size: clamp(1.05rem, 1.6vw, 1.25rem);
  line-height: 1.85;
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 2rem;
}

.topic-list {
  display: grid;
  gap: 1rem;
}

.topic {
  display: grid;
  grid-template-columns: 96px 1fr;
  gap: 1.5rem;
  align-items: center;
  padding: clamp(18px, 3vw, 32px);
  border: 1px solid var(--rule);
  background: rgba(0, 20, 41, 0.38);
}

.topic-number {
  color: var(--gold);
  font-family: Inter, Arial, sans-serif;
  font-size: clamp(2.4rem, 5vw, 4.2rem);
  font-weight: 900;
  line-height: 1;
}

.topic h3 {
  margin-bottom: 0.55rem;
  color: var(--gold-soft);
  font-size: clamp(1.35rem, 3vw, 2.4rem);
  line-height: 1.2;
}

.topic p {
  margin-bottom: 0;
  color: rgba(250, 250, 246, 0.76);
  font-size: clamp(1rem, 1.5vw, 1.18rem);
}

.speaker-section {
  background: rgba(0, 20, 41, 0.35);
}

.speaker-copy {
  border-left: 4px solid var(--gold);
  padding-left: clamp(20px, 4vw, 36px);
}

.speaker-copy p {
  margin-bottom: 1rem;
}

.join-section {
  background: var(--paper);
  color: var(--ink);
}

.meeting-code {
  display: inline-grid;
  gap: 0.35rem;
  margin-top: 1.2rem;
  padding: 1rem 1.2rem;
  border: 1px solid rgba(0, 48, 87, 0.24);
  background: var(--white);
}

.meeting-code span {
  color: #52606d;
  font-size: 0.92rem;
}

.meeting-code strong {
  color: var(--navy);
  font-size: clamp(1.8rem, 4vw, 3rem);
}

.qr-card {
  width: min(420px, 100%);
  margin: 0;
  justify-self: center;
  padding: clamp(14px, 3vw, 22px);
  background: var(--white);
  border: 1px solid rgba(0, 48, 87, 0.18);
  box-shadow: 0 20px 52px rgba(0, 48, 87, 0.14);
}

.qr-card img {
  width: 100%;
}

.qr-card figcaption {
  color: #52606d;
}

.site-footer {
  padding: 32px 0;
  background: #001429;
  border-top: 1px solid rgba(233, 191, 117, 0.18);
}

.footer-inner p {
  margin: 0;
  color: rgba(250, 250, 246, 0.66);
}

:focus-visible {
  outline: 3px solid var(--cyan);
  outline-offset: 4px;
}

@media (max-width: 880px) {
  .header-inner {
    align-items: flex-start;
    flex-direction: column;
    padding: 14px 0;
  }

  .nav {
    width: 100%;
    justify-content: space-between;
  }

  .hero-grid,
  .intro-grid,
  .speaker-grid,
  .join-grid {
    grid-template-columns: 1fr;
  }

  .poster-panel {
    order: -1;
  }

  .poster-panel img {
    max-height: none;
  }

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

  .topic-number {
    font-size: 3rem;
  }

  .footer-inner {
    align-items: flex-start;
    flex-direction: column;
  }
}

@media (max-width: 520px) {
  .shell {
    width: min(100% - 24px, 1180px);
  }

  .event-meta div {
    grid-template-columns: 1fr;
    gap: 0.25rem;
  }

  .hero-actions,
  .button {
    width: 100%;
  }

  h1 {
    font-size: clamp(2.55rem, 15vw, 4rem);
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}