:root {
  --ink: #000000;
  --muted: #5f6368;
  --line: #e3e7ee;
  --link: #0b57d0;
  --paper: #ffffff;
  --soft: #f8fafc;
  --header-bg: rgba(255, 255, 255, 0.96);
  --banner-bg: #eef3f8;
  --action-bg: #000000;
  --action-text: #ffffff;
  --action-hover: #333333;
  --logo-outer: #ffffff;
  --logo-outline: #c7d4e4;
  --notice-border: #e7b7b7;
  --notice-bg-top: #fff1f1;
  --notice-bg-bottom: #fff8f8;
  --notice-shadow: rgba(176, 42, 42, 0.08);
  --notice-accent: #b02a2a;
  color-scheme: light;
}

:root[data-theme="dark"] {
  --ink: #f4f7fb;
  --muted: #a8b3c2;
  --line: #293546;
  --link: #7fb4ff;
  --paper: #0d1117;
  --soft: #121922;
  --header-bg: rgba(13, 17, 23, 0.94);
  --banner-bg: #111a25;
  --action-bg: #7fb4ff;
  --action-text: #08111f;
  --action-hover: #a9ccff;
  --logo-outer: #192435;
  --logo-outline: #3c526c;
  --notice-border: #6c3434;
  --notice-bg-top: #2a1414;
  --notice-bg-bottom: #201011;
  --notice-shadow: rgba(255, 128, 128, 0.12);
  --notice-accent: #ff9a9a;
  color-scheme: dark;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 15px;
  line-height: 1.58;
  text-rendering: optimizeLegibility;
  overflow-x: clip;
}

a {
  color: var(--link);
  text-underline-offset: 0.18em;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 64px;
  padding: 0 max(28px, calc((100vw - 820px) / 2));
  background: var(--header-bg);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(10px);
}

.brand {
  color: var(--ink);
  font-size: 0.9rem;
  font-weight: 650;
  text-decoration: none;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 20px;
  font-size: 0.86rem;
}

.nav a {
  color: var(--ink);
  font-weight: 500;
  text-decoration: none;
}

.nav a:hover {
  color: var(--link);
}

.theme-toggle {
  display: inline-grid;
  place-items: center;
  flex: 0 0 auto;
  width: 34px;
  height: 34px;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--paper);
  color: var(--ink);
  cursor: pointer;
}

.theme-toggle:hover {
  border-color: var(--link);
  color: var(--link);
}

.theme-toggle__icon {
  grid-area: 1 / 1;
  width: 17px;
  height: 17px;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.8;
}

.theme-toggle__icon--sun,
:root[data-theme="dark"] .theme-toggle__icon--moon {
  opacity: 0;
}

:root[data-theme="dark"] .theme-toggle__icon--sun {
  opacity: 1;
}

main,
.footer {
  width: min(820px, calc(100% - 56px));
  margin: 0 auto;
}

.hero {
  padding: 0;
  border-bottom: 1px solid var(--line);
  text-align: center;
}

.hero__content {
  max-width: 820px;
  margin: 0 auto;
}

h1,
h2 {
  color: var(--ink);
  font-family: Georgia, "Times New Roman", Times, serif;
}

h3,
h4 {
  color: var(--ink);
}

h1,
h2,
h3,
h4,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 14px;
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 400;
  line-height: 1.12;
  letter-spacing: 0;
}

.title-banner {
  display: grid;
  justify-items: center;
  gap: 12px;
  width: 100vw;
  margin: 0 0 0 50%;
  padding: 40px max(28px, calc((100vw - 820px) / 2)) 34px;
  transform: translateX(-50%);
  background: var(--banner-bg);
  border-bottom: 1px solid var(--line);
}

.title-banner__logo {
  color: var(--ink);
  display: block;
  width: min(360px, 86vw);
  height: auto;
}

.title-banner__text {
  color: var(--ink);
  max-width: 680px;
  font-size: clamp(1.45rem, 3vw, 2.25rem);
  font-weight: 700;
  line-height: 1.18;
}

.title-banner__colocation {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  color: var(--muted);
  font-size: 1rem;
  font-weight: 500;
  text-decoration: none;
}

.title-banner__colocation:hover {
  color: var(--link);
}

.title-banner__colocation svg {
  width: 15px;
  height: 15px;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.8;
}

h2 {
  margin-bottom: 0;
  font-size: 1.42rem;
  font-weight: 400;
  line-height: 1.25;
  letter-spacing: 0;
}

h3 {
  margin: 28px 0 10px;
  font-size: 1.12rem;
  font-weight: 650;
}

h4 {
  margin: 0 0 6px;
  font-size: 1rem;
  font-weight: 600;
}

.meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 14px 34px;
  margin-top: 2px;
  margin-bottom: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.meta__item {
  display: inline-flex;
  align-items: center;
  gap: 7px;
}

.meta__item svg {
  width: 16px;
  height: 16px;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.8;
}

.section {
  padding: 44px 0;
  border-bottom: 1px solid var(--line);
  scroll-margin-top: 82px;
}

.section__heading {
  margin-bottom: 22px;
}

.section__heading p {
  margin: 12px 0 0;
  color: var(--muted);
  font-size: 0.88rem;
}

.section__body {
  max-width: 100%;
}

.prose {
  color: var(--muted);
}

.prose p {
  margin-bottom: 16px;
}

.agenda-list {
  display: grid;
  gap: 0;
  margin: 18px 0 8px;
}

.agenda-item {
  display: grid;
  grid-template-columns: 190px minmax(0, 1fr);
  gap: 22px;
  padding: 8px 0;
  border-top: 1px solid var(--line);
}

.agenda-item:last-child {
  border-bottom: 1px solid var(--line);
}

.agenda-item time {
  color: var(--muted);
}

.agenda-item span {
  color: var(--muted);
  font-weight: 500;
}

.topic-list {
  margin: 0 0 18px;
  padding-left: 20px;
  list-style-type: disc;
}

.topic-list li {
  margin-bottom: 6px;
}

.important-dates {
  display: grid;
  gap: 18px;
  margin: 10px 0 22px;
}

.important-dates__group {
  padding: 18px 18px 16px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: linear-gradient(180deg, var(--soft), var(--paper));
}

.important-dates__heading {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 12px;
  font-size: 1.12rem;
  font-weight: 700;
}

.important-dates__heading-icon {
  width: 18px;
  height: 18px;
  fill: none;
  stroke: var(--link);
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.9;
}

.important-dates__list {
  display: grid;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.important-dates__item {
  display: grid;
  grid-template-columns: 18px minmax(0, 1fr);
  gap: 10px;
  align-items: start;
}

.important-dates__item-icon {
  width: 18px;
  height: 18px;
  margin-top: 0.15em;
  fill: none;
  stroke: var(--action-bg);
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 2;
}

.important-dates__item strong {
  color: var(--ink);
}

.topic-groups {
  display: grid;
  gap: 14px;
  margin: 4px 0 26px;
  padding: 0;
  list-style: none;
  counter-reset: topic;
}

.topic-groups > li {
  position: relative;
  padding-left: 30px;
  counter-increment: topic;
}

.topic-groups > li::before {
  position: absolute;
  top: 1px;
  left: 0;
  color: var(--ink);
  content: counter(topic) ".";
  font-size: 0.94rem;
  font-weight: 650;
  line-height: 1.58;
}

.topic-groups h4 {
  font-weight: 600;
}

.topic-groups ul {
  margin: 0;
  padding-left: 18px;
  list-style-type: disc;
}

.topic-groups li li {
  margin-bottom: 4px;
}

.text-link {
  font-weight: 650;
}

.publications-registration__heading {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 8px 14px;
  border: 1px solid var(--notice-border);
  border-radius: 999px;
  background: linear-gradient(180deg, var(--notice-bg-top), var(--notice-bg-bottom));
  box-shadow: inset 0 0 0 1px var(--notice-shadow);
  color: var(--ink);
}

.publications-registration__icon {
  width: 18px;
  height: 18px;
  flex: 0 0 auto;
  fill: none;
  stroke: var(--notice-accent);
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.8;
}

.action-link {
  display: inline-flex;
  align-items: center;
  min-height: 36px;
  padding: 8px 13px;
  border: 1px solid var(--action-bg);
  border-radius: 6px;
  background: var(--action-bg);
  color: var(--action-text);
  font-size: 0.9rem;
  font-weight: 650;
  line-height: 1.2;
  text-decoration: none;
}

.action-link:hover {
  border-color: var(--action-hover);
  background: var(--action-hover);
  color: var(--paper);
}

.people-list {
  display: grid;
  gap: 18px;
}

.organizer-sections {
  display: grid;
  gap: 16px;
}

.organizer-section-title {
  margin: 0 0 8px;
}

.leadership-block {
  display: grid;
  gap: 6px;
}

.featured-role-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(220px, 280px));
  gap: 10px;
  align-items: stretch;
  justify-content: center;
}

.leadership-group {
  display: grid;
  gap: 4px;
}

.leadership-group--single {
  justify-items: center;
}

.leadership-group__title {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
}

.leadership-group--single .leadership-group__title {
  justify-content: center;
  text-align: center;
}

.leadership-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 8px;
}

.leadership-grid--four {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.leadership-grid--five {
  grid-template-columns: repeat(5, minmax(0, 1fr));
}

.leadership-grid--single {
  grid-template-columns: minmax(0, 1fr);
  justify-items: center;
}

.leadership-card {
  display: grid;
  grid-template-rows: auto auto 1fr;
  justify-items: center;
  align-content: start;
  gap: 2px;
  height: 100%;
  width: min(100%, 260px);
  padding: 8px 10px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: linear-gradient(180deg, var(--soft), var(--paper));
  color: var(--ink);
  text-align: center;
  text-decoration: none;
  box-shadow: 0 10px 24px rgba(15, 23, 42, 0.04);
}

.leadership-card:hover {
  border-color: var(--link);
  transform: translateY(-1px);
}

.leadership-card img {
  width: 104px;
  height: 104px;
  border-radius: 999px;
  object-fit: cover;
  object-position: center top;
}

.leadership-card__placeholder {
  display: grid;
  place-items: center;
  width: 104px;
  height: 104px;
  border-radius: 999px;
  background: linear-gradient(180deg, var(--soft), var(--banner-bg));
  color: var(--ink);
  font-size: 1.8rem;
  font-weight: 650;
}

.leadership-card strong {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  min-height: 1.65em;
  font-size: 1rem;
  font-weight: 650;
  line-height: 1.25;
}

.leadership-card span {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  min-height: 1.55em;
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.3;
}

.speaker-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.speaker-card {
  display: grid;
  justify-items: center;
  gap: 8px;
  padding: 22px 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--ink);
  text-align: center;
  text-decoration: none;
}

.speaker-card:hover {
  border-color: var(--link);
}

.speaker-card img {
  width: 96px;
  height: 96px;
  margin-bottom: 6px;
  border-radius: 999px;
}

.speaker-card strong {
  font-size: 1rem;
  font-weight: 650;
}

.speaker-card span {
  color: var(--muted);
  font-size: 0.86rem;
  line-height: 1.4;
}

.speaker-card p {
  margin: 4px 0 0;
  color: var(--muted);
  font-size: 0.88rem;
  line-height: 1.5;
}

.people-list--compact {
  gap: 14px;
}

.people-list--dense {
  gap: 8px;
}

.organizer-groups {
  display: grid;
  gap: 10px;
}

.organizer-group h3 {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 6px;
}

.organizer-status {
  display: inline-flex;
  align-items: center;
  padding: 2px 8px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--soft);
  color: var(--muted);
  font-size: 0.76rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  vertical-align: middle;
}

.person {
  display: grid;
  gap: 3px;
  padding: 0;
  color: var(--ink);
  text-decoration: none;
}

.person:hover strong {
  color: var(--link);
}

.person strong {
  font-weight: 650;
}

.person span,
.person em {
  color: var(--muted);
  font-size: 0.9rem;
  font-style: normal;
}

.footer {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 30px 0 44px;
  color: var(--muted);
  font-size: 0.85rem;
}

@media (max-width: 780px) {
  .site-header {
    position: static;
    align-items: flex-start;
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 8px;
    padding: 16px 22px;
  }

  .theme-toggle {
    width: 44px;
    height: 44px;
  }

  .nav {
    grid-column: 1 / -1;
    justify-content: flex-start;
    gap: 10px 16px;
  }

  main,
  .footer {
    width: min(100% - 36px, 820px);
  }

  .hero {
    padding: 0;
  }

  .title-banner {
    padding-top: 34px;
    padding-bottom: 30px;
  }

  .title-banner__text {
    font-size: clamp(1.3rem, 4.8vw, 1.9rem);
  }

  .title-banner__colocation {
    font-size: 0.95rem;
  }

  .section {
    padding: 40px 0;
  }

  .agenda-item {
    grid-template-columns: 1fr;
    gap: 2px;
  }

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

  .leadership-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 8px;
  }

  .featured-role-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 8px;
  }

  .leadership-card {
    width: 100%;
    padding: 10px 8px;
    border-radius: 16px;
  }

  .leadership-card img,
  .leadership-card__placeholder {
    width: 84px;
    height: 84px;
  }

  .leadership-card strong {
    min-height: auto;
    font-size: 0.94rem;
  }

  .leadership-card span {
    min-height: auto;
    font-size: 0.82rem;
    line-height: 1.35;
  }

  .people-list--dense {
    gap: 6px;
  }

  .person {
    gap: 1px;
  }

  .person strong {
    font-size: 0.95rem;
  }

  .person span,
  .person em {
    font-size: 0.84rem;
    line-height: 1.35;
  }

  .footer {
    flex-direction: column;
  }
}

@media (max-width: 520px) {
  .site-header {
    padding-left: 16px;
    padding-right: 16px;
  }

  .featured-role-grid {
    grid-template-columns: 1fr;
    justify-items: center;
  }

  .featured-role-grid .leadership-group {
    width: 100%;
  }

  .featured-role-grid .leadership-card {
    max-width: 240px;
  }

  .title-banner {
    padding-top: 28px;
    padding-bottom: 24px;
  }

  .title-banner__text {
    font-size: clamp(1.2rem, 5vw, 1.65rem);
  }

  .title-banner__colocation {
    font-size: 0.9rem;
    line-height: 1.35;
    text-align: center;
  }
}