:root {
  --bg: #f3f6f8;
  --surface: #ffffff;
  --surface-soft: #e7eff5;
  --ink: #1a2a33;
  --muted: #5a6d7b;
  --line: #ced9e2;
  --brand: #0b5c7a;
  --brand-strong: #083f55;
  --accent: #b66a2e;
  --accent-soft: #f3e6d8;
  --focus: #0f7fa7;
  --radius: 14px;
  --radius-sm: 10px;
  --shadow: 0 14px 34px rgba(8, 35, 47, 0.08);
  --container: 1120px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "IBM Plex Sans", "Segoe UI", sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at 8% -2%, #d8e9f2 0%, transparent 36%),
    radial-gradient(circle at 94% 16%, #f7e9da 0%, transparent 28%),
    var(--bg);
  line-height: 1.55;
}

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

a {
  color: var(--brand);
  text-decoration: none;
}

a:hover {
  color: var(--brand-strong);
}

h1,
h2,
h3,
h4 {
  margin: 0;
  font-family: "Source Serif 4", Georgia, serif;
  font-weight: 600;
  line-height: 1.2;
  color: var(--ink);
}

p {
  margin: 0;
}

.container {
  width: min(var(--container), calc(100% - 2.25rem));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 90;
  border-bottom: 1px solid rgba(12, 50, 69, 0.09);
  background: rgba(243, 246, 248, 0.94);
  backdrop-filter: blur(8px);
}

.header-inner {
  display: flex;
  gap: 1rem;
  align-items: center;
  padding: 0.85rem 0;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--ink);
  flex-shrink: 0;
}

.brand-mark {
  display: inline-grid;
  place-items: center;
  width: 2.05rem;
  height: 2.05rem;
  border-radius: 999px;
  background: linear-gradient(145deg, var(--brand), #0c7197);
  color: #fff;
  font-weight: 700;
  font-size: 0.95rem;
  letter-spacing: 0.02em;
}

.brand-text {
  display: grid;
  line-height: 1.2;
}

.brand-title {
  font-size: 0.95rem;
  font-weight: 700;
}

.brand-subtitle {
  font-size: 0.72rem;
  color: var(--muted);
  font-weight: 500;
}

.nav-toggle {
  margin-left: auto;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--ink);
  border-radius: 9px;
  padding: 0.45rem 0.7rem;
  font-weight: 600;
  display: none;
}

.nav-toggle:focus-visible,
.nav-links a:focus-visible,
.nav-more summary:focus-visible,
.btn:focus-visible,
.text-link:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--focus) 44%, transparent);
  outline-offset: 2px;
}

.site-nav {
  margin-left: auto;
}

.nav-links {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  flex-wrap: nowrap;
  gap: 0.35rem;
}

.nav-links a {
  display: inline-block;
  padding: 0.45rem 0.62rem;
  border-radius: 8px;
  color: var(--muted);
  font-size: 0.8rem;
  font-weight: 600;
  transition: color 160ms ease, background-color 160ms ease;
}

.nav-links a:hover {
  color: var(--brand-strong);
  background: #e6eff5;
}

.nav-links a[aria-current="page"] {
  background: #dbe8f1;
  color: var(--brand-strong);
}

.nav-more {
  position: relative;
}

.nav-more details {
  position: relative;
}

.nav-more summary {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.45rem 0.62rem;
  border-radius: 8px;
  color: var(--muted);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
  transition: color 160ms ease, background-color 160ms ease;
}

.nav-more summary::-webkit-details-marker {
  display: none;
}

.nav-more summary::after {
  content: "";
  width: 0.42rem;
  height: 0.42rem;
  border-right: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: rotate(45deg) translateY(-1px);
  transition: transform 160ms ease;
}

.nav-more details[open] summary::after {
  transform: rotate(225deg) translateY(-1px);
}

.nav-more summary:hover {
  color: var(--brand-strong);
  background: #e6eff5;
}

.nav-more summary[aria-current="page"] {
  background: #dbe8f1;
  color: var(--brand-strong);
}

.nav-more-list {
  list-style: none;
  margin: 0.35rem 0 0;
  padding: 0.35rem;
  position: absolute;
  right: 0;
  top: 100%;
  min-width: 240px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--surface);
  box-shadow: var(--shadow);
  display: grid;
  gap: 0.2rem;
  z-index: 110;
}

.nav-more-list li {
  margin: 0;
}

.nav-more-list a {
  display: block;
  width: 100%;
}

.page-content {
  padding: 2rem 0 3rem;
  display: grid;
  gap: 1.25rem;
}

.page-hero {
  background:
    linear-gradient(160deg, rgba(11, 92, 122, 0.9), rgba(8, 63, 85, 0.93)),
    linear-gradient(12deg, #0f85ac, transparent);
  border-radius: calc(var(--radius) + 4px);
  color: #f6fbff;
  padding: clamp(1.4rem, 3vw, 2.1rem);
  box-shadow: var(--shadow);
  display: grid;
  gap: 0.6rem;
}

.kicker {
  font-size: 0.82rem;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  font-weight: 700;
  opacity: 0.95;
}

.page-hero h1 {
  color: #ffffff;
  font-size: clamp(1.8rem, 3.8vw, 2.55rem);
}

.page-hero .lead {
  max-width: 75ch;
  color: #e4f4fb;
}

.hero-cta {
  margin-top: 0.45rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  border: 1px solid transparent;
  padding: 0.62rem 0.9rem;
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  transition: transform 160ms ease, box-shadow 160ms ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: #ffffff;
  color: var(--brand-strong);
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.12);
}

.btn-secondary {
  color: #f6fbff;
  border-color: rgba(228, 244, 251, 0.7);
  background: rgba(4, 41, 57, 0.2);
}

.page-section {
  background: var(--surface);
  border: 1px solid rgba(17, 74, 97, 0.1);
  border-radius: var(--radius);
  padding: clamp(1.1rem, 2.3vw, 1.45rem);
  box-shadow: var(--shadow);
  display: grid;
  gap: 0.9rem;
}

.page-section h2 {
  font-size: clamp(1.35rem, 2.2vw, 1.65rem);
}

.section-intro {
  color: var(--muted);
  max-width: 86ch;
}

.grid-two {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.stack {
  display: grid;
  gap: 0.75rem;
}

.bullet-list {
  margin: 0;
  padding-left: 1.1rem;
  display: grid;
  gap: 0.55rem;
}

.bullet-list li {
  color: var(--ink);
}

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

.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  border-radius: 999px;
  padding: 0.2rem 0.6rem;
  font-size: 0.77rem;
  font-weight: 600;
  background: #e8f2f7;
  color: var(--brand-strong);
  width: fit-content;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(225px, 1fr));
  gap: 0.85rem;
}

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

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

#sponsor-tiers .card-grid {
  align-items: start;
}

.info-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 0.95rem;
  display: grid;
  gap: 0.5rem;
}

.info-card h3 {
  font-size: 1.1rem;
}

.soft-panel {
  background: var(--surface-soft);
  border-radius: var(--radius-sm);
  border: 1px solid #d3e2ec;
  padding: 0.95rem;
}

.timeline {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 0.75rem;
}

.timeline li {
  border: 1px solid var(--line);
  border-left: 5px solid #0f6e91;
  border-radius: var(--radius-sm);
  padding: 0.75rem 0.85rem;
  background: #fbfdff;
}

.timeline strong {
  display: block;
  font-size: 1rem;
}

.schedule-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 0.95rem;
}

.schedule-day {
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: #ffffff;
  padding: 0.95rem;
  display: grid;
  gap: 0.75rem;
}

.schedule-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 0.65rem;
}

.schedule-item {
  border-left: 4px solid #1a7aa0;
  background: #f8fbfd;
  border-radius: 0 8px 8px 0;
  padding: 0.5rem 0.65rem;
}

.schedule-time {
  font-size: 0.8rem;
  color: var(--muted);
  font-weight: 600;
}

.person-card {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.75rem;
  align-items: start;
}

.avatar {
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 999px;
  background: linear-gradient(150deg, #0c749a, #0a4b65);
  color: #fff;
  display: grid;
  place-items: center;
  font-weight: 700;
  font-size: 0.87rem;
  position: relative;
  overflow: hidden;
}

.avatar-image {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

#speakers-grid .avatar {
  width: 5rem;
  height: 5rem;
  border-radius: 0.7rem;
  font-size: 1rem;
}

.person-meta {
  display: grid;
  gap: 0.3rem;
}

.person-role {
  font-size: 0.84rem;
  color: var(--muted);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.data-table th,
.data-table td {
  border: 1px solid var(--line);
  padding: 0.65rem;
  text-align: left;
  vertical-align: top;
  font-size: 0.92rem;
}

.data-table th {
  background: #eaf2f8;
  font-weight: 700;
}

.callout {
  border-left: 5px solid var(--accent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: var(--accent-soft);
  padding: 0.82rem 0.9rem;
}

.link-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 0.5rem;
}

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-weight: 600;
}

.site-footer {
  padding: 1.7rem 0 2.3rem;
  color: var(--muted);
}

.footer-panel {
  border-top: 1px solid rgba(12, 50, 69, 0.15);
  padding-top: 1rem;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.8rem;
}

@media (max-width: 1080px) {
  .nav-links a,
  .nav-more summary {
    padding: 0.4rem 0.5rem;
    font-size: 0.76rem;
  }
}

@media (max-width: 900px) {
  .header-inner {
    flex-wrap: wrap;
  }

  .nav-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

  .site-nav {
    width: 100%;
    position: relative;
  }

  .nav-links {
    display: none;
    grid-template-columns: 1fr;
    gap: 0.25rem;
    width: 100%;
  }

  .nav-links[data-open="true"] {
    display: grid;
    margin-top: 0.45rem;
    padding: 0.35rem;
    border: 1px solid var(--line);
    border-radius: 12px;
    background: var(--surface);
    box-shadow: var(--shadow);
    max-height: min(68vh, 440px);
    overflow-y: auto;
    overscroll-behavior: contain;
    -webkit-overflow-scrolling: touch;
  }

  .nav-links a {
    padding: 0.62rem 0.78rem;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #f8fbfd;
  }

  .nav-more {
    display: none;
  }

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

@media (max-width: 620px) {
  .container {
    width: min(var(--container), calc(100% - 1.3rem));
  }

  .page-content {
    padding-top: 1.2rem;
    gap: 0.95rem;
  }

  .page-hero {
    border-radius: 14px;
  }

  .page-section {
    padding: 0.95rem;
  }

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