:root {
  --bg: #ffffff;
  --ink: #14161a;
  --ink-soft: #6b7078;
  --line: #e6e5e1;
  --accent: #1c3f6e;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  overflow-x: hidden;
}

body {
  margin: 0;
  overflow-x: hidden;
  font-family: "IBM Plex Sans", "Segoe UI", sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.6;
}

a {
  color: var(--accent);
}

p {
  text-align: justify;
  text-justify: inter-word;
  hyphens: auto;
}

.container {
  width: min(1180px, calc(100% - 3.2rem));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(8px);
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.05rem 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  font-family: "Manrope", sans-serif;
  font-weight: 700;
  font-size: 0.94rem;
  color: var(--ink);
  text-decoration: none;
}

.brand-logo {
  display: block;
  width: auto;
  height: 32px;
}

.nav-links {
  display: flex;
  flex-wrap: wrap;
  list-style: none;
  margin: 0;
  padding: 0;
  gap: 1.4rem;
}

.nav-links a {
  text-decoration: none;
  color: var(--ink-soft);
  font-weight: 500;
  font-size: 0.9rem;
  transition: color 160ms ease;
}

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

.hero {
  padding: 4.5rem 0 3rem;
  background: #ffffff;
}

.robot-gallery-section {
  margin: 0 auto 3rem;
}

.robot-gallery {
  display: grid;
  gap: 1.4rem;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

.robot-gallery figure {
  margin: 0;
}

.robot-gallery img {
  display: block;
  width: 100%;
  height: 300px;
  object-fit: contain;
  background: #f3f1ea;
  border-radius: 4px;
}

.robot-gallery figcaption {
  margin-top: 0.5rem;
  color: var(--ink-soft);
  font-size: 0.8rem;
  line-height: 1.5;
}

.robot-gallery figcaption a {
  color: var(--ink-soft);
}

.robot-gallery-video video {
  display: block;
  width: min(100%, 900px);
  height: auto;
  margin: 0 auto;
  border-radius: 4px;
}

.kicker {
  margin: 0;
  color: var(--ink-soft);
  font-weight: 600;
  font-size: 0.78rem;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  font-family: "Manrope", sans-serif;
  line-height: 1.22;
  color: var(--ink);
  font-weight: 700;
}

h1 {
  margin: 0.7rem 0 0;
  font-size: clamp(1.9rem, 4.4vw, 2.6rem);
  letter-spacing: -0.02em;
  font-weight: 800;
}

h2 {
  margin: 0;
  font-size: clamp(1.2rem, 2.4vw, 1.5rem);
}

h3 {
  margin: 0;
  font-size: 1rem;
  font-weight: 700;
}

.hero-subtitle,
#overview-text,
#cfp-intro,
#venue-text {
  margin: 0.9rem 0 0;
  color: var(--ink-soft);
  max-width: 92ch;
  font-size: 1.02rem;
}

.hero-meta {
  margin-top: 2rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0 2.2rem;
}

.meta-item {
  padding: 0;
  min-width: 140px;
}

.meta-item span {
  display: block;
  font-size: 0.74rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.meta-item strong {
  display: block;
  margin-top: 0.2rem;
  font-weight: 600;
  color: var(--ink);
}

.cta-row {
  margin-top: 1.8rem;
  display: flex;
  gap: 0.7rem;
  flex-wrap: wrap;
}

.btn {
  border-radius: 6px;
  padding: 0.6rem 1.05rem;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.92rem;
  border: 1px solid var(--ink);
  transition: opacity 140ms ease;
}

.btn:hover {
  opacity: 0.75;
}

.btn-primary {
  color: #fff;
  background: var(--ink);
}

.btn-secondary {
  color: var(--ink);
  background: transparent;
}

.section {
  padding: 3rem 0;
  border-top: 1px solid var(--line);
}

.subheading {
  margin-top: 1.9rem;
  margin-bottom: 0.7rem;
  font-size: 0.95rem;
  color: var(--ink);
}

.section-note {
  margin: 0.5rem 0 0;
  color: var(--ink-soft);
  font-size: 0.92rem;
  max-width: 92ch;
}

/* Content grids: minimal, no card chrome — plain text separated by hairlines */

.cards-grid {
  margin-top: 1.4rem;
  display: grid;
  gap: 1.6rem 1.8rem;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.speaker-grid {
  gap: 1.6rem 1.2rem;
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.schedule-list {
  grid-template-columns: 1fr;
  gap: 0;
}

.schedule-list .card {
  padding: 1rem 0;
}

.card {
  padding-top: 0.9rem;
  border-top: 1px solid var(--line);
}

.card h3 {
  margin: 0;
  min-height: 2.5rem;
}

.schedule-list .card h3 {
  min-height: 0;
}

.card p {
  margin: 0.4rem 0 0;
  color: var(--ink-soft);
  font-size: 0.92rem;
}

.tag-list {
  margin: 0.8rem 0 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 0.7rem;
}

.tag-list li {
  color: var(--ink-soft);
  font-size: 0.9rem;
  padding-right: 0.7rem;
  border-right: 1px solid var(--line);
}

.tag-list li:last-child {
  border-right: none;
  padding-right: 0;
}

.plain-list {
  margin: 0.7rem 0 0;
  padding-left: 1.1rem;
  color: var(--ink-soft);
}

.plain-list li {
  margin-bottom: 0.4rem;
}

/* Organizer & speaker person entries */

.person-card {
  padding-top: 1rem;
  border-top: 1px solid var(--line);
}

.person-card h3 {
  margin-top: 0.1rem;
}

.speaker-grid .person-card h3 {
  font-size: 1.12rem;
}

.person-title,
.person-affiliation {
  margin: 0.3rem 0 0;
  color: var(--ink-soft);
  font-size: 0.88rem;
}

.person-title {
  font-weight: 600;
  color: var(--ink);
}

.person-bio {
  margin: 0.55rem 0 0;
  color: var(--ink-soft);
  font-size: 0.88rem;
}

.person-links {
  margin: 0.6rem 0 0;
  font-size: 0.86rem;
}

.person-links a {
  font-weight: 600;
  text-decoration: none;
}

.person-links a:hover {
  text-decoration: underline;
}

.person-photo {
  width: 108px;
  height: 108px;
  border-radius: 50%;
  object-fit: cover;
  object-position: top center;
  display: block;
  margin-bottom: 0.7rem;
}

.organizer-rows {
  margin-top: 0.6rem;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  column-gap: 2rem;
  row-gap: 0;
}

.person-card--row {
  display: flex;
  align-items: flex-start;
  gap: 1.1rem;
  padding: 1.1rem 0;
}

.person-card--row .person-photo {
  flex-shrink: 0;
  width: 132px;
  height: 132px;
  margin-bottom: 0;
}

.person-card--row .person-photo-frame--zoom {
  flex-shrink: 0;
  display: block;
  width: 132px;
  height: 132px;
  overflow: hidden;
  border-radius: 50%;
}

.person-card--row .person-photo-frame--zoom .person-photo {
  width: 100%;
  height: 100%;
  margin: 0;
  border-radius: 0;
  object-position: center center;
  transform: scale(1.45);
}

.speaker-grid .person-photo {
  width: 132px;
  height: 132px;
}

.person-card--row .person-content {
  flex: 1;
  min-width: 0;
}

.person-card--row .person-content h3 {
  min-height: 0;
}

.person-card--row .person-title,
.person-card--row .person-affiliation,
.person-card--row .person-bio {
  max-width: 60ch;
}

.organizer-group {
  margin-top: 1.8rem;
}

.organizer-group:first-child {
  margin-top: 1.4rem;
}

.organizer-group-label {
  margin: 0 0 0.6rem;
  color: var(--ink-soft);
  font-weight: 600;
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.site-footer {
  border-top: 1px solid var(--line);
  padding: 1.6rem 0 2.4rem;
  color: var(--ink-soft);
}

.footer-wrap {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.6rem;
  font-size: 0.88rem;
}

.footer-wrap strong {
  color: var(--ink);
  font-weight: 600;
}

.reveal {
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 380ms ease, transform 380ms ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 820px) {
  .nav-wrap {
    align-items: flex-start;
    flex-direction: column;
  }

  .hero {
    padding-top: 2.75rem;
  }

  .section {
    padding: 2.2rem 0;
  }

  .speaker-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 1100px) and (min-width: 821px) {
  .speaker-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (max-width: 560px) {
  .speaker-grid {
    grid-template-columns: 1fr;
  }
}