/* ===== CSS VARIABLES — DexHoldem-inspired palette ===== */
:root {
  --paper:       #fbfaf6;
  --paper-deep:  #f1ede5;
  --ink:         #151820;
  --ink-soft:    #303746;
  --muted:       #64707f;
  --line:        #ded7cc;
  --accent:      #9d302d;
  --accent-dark: #6f1f1e;
  --blue:        #2d5f9d;
  --green:       #2f7459;
  --gold:        #9a7430;
  --shadow:      0 18px 45px rgba(20,24,32,0.12);
  --shadow-sm:   0 4px 16px rgba(20,24,32,0.08);
  --radius:      8px;

  --font-display: Georgia, "Times New Roman", serif;
  --font-body:    Inter, ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono:    "SFMono-Regular", Consolas, "Liberation Mono", monospace;
}

/* ===== RESET ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--paper);
  line-height: 1.65;
  overflow-x: hidden;
}
img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }

/* ===== NAV ===== */
#navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 66px;
  padding: 0 clamp(20px, 5vw, 72px);
  color: #fff;
  border-bottom: 1px solid rgba(255,255,255,0.16);
  background: rgba(18,20,24,0.36);
  backdrop-filter: blur(16px);
  transition: background 200ms ease, color 200ms ease,
              box-shadow 200ms ease, border-color 200ms ease;
}
#navbar.scrolled {
  color: var(--ink);
  background: rgba(251,250,246,0.94);
  border-bottom-color: rgba(38,43,52,0.12);
  box-shadow: 0 8px 28px rgba(20,24,32,0.08);
}
.nav-inner {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-brand {
  font-weight: 800;
  font-size: 0.95rem;
  letter-spacing: 0.01em;
  white-space: nowrap;
}
.nav-links {
  list-style: none;
  display: flex;
  gap: clamp(14px, 2.4vw, 30px);
}
.nav-links a {
  font-size: 0.91rem;
  font-weight: 650;
  opacity: 0.85;
  transition: opacity 160ms;
  position: relative;
}
.nav-links a::after {
  content: '';
  position: absolute;
  left: 0; right: 0; bottom: -8px;
  height: 2px;
  background: currentColor;
  opacity: 0;
  transform: scaleX(0.6);
  transition: opacity 160ms, transform 160ms;
}
.nav-links a:hover,
.nav-links a.active { opacity: 1; }
.nav-links a:hover::after,
.nav-links a.active::after { opacity: 0.75; transform: scaleX(1); }

/* ===== HERO ===== */
#hero {
  min-height: 100svh;
  display: grid;
  align-content: end;
  gap: 28px;
  padding: 140px clamp(20px, 5vw, 72px) 56px;
  color: #fff;
  overflow: hidden;
  background:
    linear-gradient(90deg, rgba(11,13,17,0.92) 0%, rgba(11,13,17,0.68) 46%, rgba(11,13,17,0.18) 100%),
    linear-gradient(135deg, #0f172a 0%, #1e1b4b 45%, #0e7490 100%);
  position: relative;
}
#hero::after {
  content: '';
  position: absolute; inset: 0;
  background:
    linear-gradient(0deg, rgba(11,13,17,0.38), rgba(11,13,17,0.02) 48%),
    radial-gradient(circle at 75% 22%, rgba(157,48,45,0.14), transparent 26%),
    radial-gradient(ellipse 70% 55% at 20% 50%, rgba(99,102,241,0.18), transparent 60%);
  pointer-events: none;
}
.hero-overlay { display: none; }
.hero-content {
  position: relative;
  z-index: 1;
  max-width: 860px;
}
.hero-tag {
  display: inline-block;
  background: rgba(157,48,45,0.30);
  border: 1px solid rgba(157,48,45,0.55);
  color: rgba(255,255,255,0.90);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.10em;
  text-transform: uppercase;
  padding: 5px 16px;
  border-radius: 4px;
  margin-bottom: 24px;
}
.hero-title {
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 6vw, 5rem);
  font-weight: 700;
  line-height: 1.0;
  color: #fff;
  margin-bottom: 12px;
}
.hero-title span {
  display: block;
  font-size: clamp(1.3rem, 3vw, 2.2rem);
  font-weight: 400;
  font-style: italic;
  color: rgba(255,255,255,0.80);
  margin-top: 10px;
  line-height: 1.3;
}
.hero-meta {
  color: rgba(255,255,255,0.60);
  font-size: 0.94rem;
  margin: 22px 0 38px;
}
.hero-meta a { color: rgba(255,255,255,0.85); text-decoration: underline; text-underline-offset: 3px; }
.hero-btns {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}
.btn {
  padding: 11px 26px;
  border-radius: 6px;
  font-weight: 700;
  font-size: 0.91rem;
  transition: all 0.18s;
  cursor: pointer;
  display: inline-block;
  letter-spacing: 0.01em;
}
.btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 4px 18px rgba(157,48,45,0.40);
}
.btn-primary:hover {
  background: var(--accent-dark);
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(157,48,45,0.52);
}
.btn-outline {
  background: transparent;
  color: #fff;
  border: 1.5px solid rgba(255,255,255,0.42);
}
.btn-outline:hover {
  background: rgba(255,255,255,0.10);
}

/* ===== STATS BAR ===== */
#stats {
  background: var(--ink);
  padding: 36px clamp(20px, 5vw, 72px);
}
.stats-grid {
  max-width: 900px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  text-align: center;
}
.stat-num {
  display: block;
  font-family: var(--font-display);
  font-size: 2.4rem;
  font-weight: 700;
  color: #fff;
  line-height: 1;
}
.stat-label {
  display: block;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.50);
  margin-top: 8px;
}

/* ===== SECTIONS ===== */
.section { padding: clamp(56px, 7vw, 88px) clamp(20px, 5vw, 72px); }
.section-alt { background: var(--paper-deep); }
.container { max-width: 1100px; margin: 0 auto; }

.section-title {
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 4vw, 3.2rem);
  font-weight: 700;
  color: var(--ink);
  line-height: 1.1;
  margin-bottom: 8px;
}
.eyebrow {
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 800;
  letter-spacing: 0.10em;
  text-transform: uppercase;
  margin-bottom: 12px;
}
.section-sub {
  color: var(--muted);
  font-size: 1rem;
  margin: 14px 0 40px;
  max-width: 680px;
}

/* ===== OVERVIEW ===== */
.overview-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 52px;
  margin-top: 40px;
  align-items: start;
}
.overview-text p {
  margin-bottom: 18px;
  color: var(--ink-soft);
  font-size: 0.97rem;
}
.overview-topics {
  background: rgba(255,255,255,0.58);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 32px;
  box-shadow: var(--shadow-sm);
}
.overview-topics h3 {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 16px;
}
.overview-topics ul { list-style: none; padding: 0; }
.overview-topics li {
  padding: 8px 12px 8px 32px;
  position: relative;
  font-size: 0.91rem;
  color: var(--ink-soft);
  border-bottom: 1px solid var(--line);
  border-radius: 4px;
  transition: background 0.18s, color 0.18s;
  cursor: default;
}
.overview-topics li:last-child { border-bottom: none; }
.overview-topics li:hover {
  background: rgba(157,48,45,0.07);
  color: var(--ink);
}
.overview-topics li::before {
  content: '▸';
  position: absolute;
  left: 10px;
  color: var(--accent);
  font-size: 0.75rem;
  top: 10px;
  transition: transform 0.18s;
}
.overview-topics li:hover::before {
  transform: translateX(3px);
}

/* ===== SPEAKERS ===== */
.speakers-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 20px;
  margin-top: 40px;
}
.speaker-card {
  background: rgba(255,255,255,0.58);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px 16px 20px;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 14px;
  transition: transform 0.18s, box-shadow 0.18s;
}
.speaker-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow);
}
.speaker-avatar {
  width: 100px;
  height: 100px;
  border-radius: 50%;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 800;
  font-size: 1.5rem;
  object-fit: cover;
}
/* keep original gradient colours */
.speaker-avatar.g1 { background: linear-gradient(135deg, #6366f1, #8b5cf6); }
.speaker-avatar.g2 { background: linear-gradient(135deg, #06b6d4, #3b82f6); }
.speaker-avatar.g3 { background: linear-gradient(135deg, #f59e0b, #ef4444); }
.speaker-avatar.g4 { background: linear-gradient(135deg, #10b981, #06b6d4); }
.speaker-avatar.g5 { background: linear-gradient(135deg, #ec4899, #8b5cf6); }

.speaker-info h3 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 4px;
  line-height: 1.3;
}
.speaker-info h3 a {
  color: var(--ink);
  text-decoration: none;
  transition: color 0.16s;
}
.speaker-info h3 a:hover {
  color: var(--accent);
}
.affil {
  font-size: 0.80rem;
  color: var(--blue);
  font-weight: 700;
  letter-spacing: 0.03em;
  margin-bottom: 0;
}
.bio {
  font-size: 0.84rem;
  color: var(--muted);
  line-height: 1.55;
}

/* ===== CHALLENGE ===== */
.challenge-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-top: 40px;
}
.challenge-single {
  grid-template-columns: 1fr;
}
.challenge-card {
  background: rgba(255,255,255,0.58);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px;
  position: relative;
  border-top: 3px solid var(--accent);
}
.challenge-card:nth-child(2) { border-top-color: var(--blue); }
.challenge-badge {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  padding: 3px 12px;
  border-radius: 4px;
  margin-bottom: 14px;
  text-transform: uppercase;
}
.challenge-card:nth-child(2) .challenge-badge { background: var(--blue); }
.challenge-card h3 {
  font-family: var(--font-display);
  font-size: 1.12rem;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 12px;
  line-height: 1.35;
}
.challenge-card > p {
  font-size: 0.92rem;
  color: var(--ink-soft);
  margin-bottom: 18px;
}
.challenge-detail {
  background: var(--paper-deep);
  border-radius: 6px;
  padding: 12px 16px;
  margin-bottom: 10px;
  border: 1px solid var(--line);
}
.challenge-detail h4 {
  font-size: 0.72rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  margin-bottom: 5px;
}
.challenge-detail p { font-size: 0.86rem; color: var(--muted); }
.challenge-footer {
  margin-top: 24px;
  padding: 18px 24px;
  background: rgba(157,48,45,0.06);
  border-radius: var(--radius);
  border: 1px solid rgba(157,48,45,0.18);
  text-align: center;
  font-size: 0.92rem;
  color: var(--ink-soft);
}
.challenge-coming-soon {
  margin-top: 18px;
  display: flex;
  justify-content: flex-start;
}
.coming-soon-btn {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 8px 20px;
  border-radius: 20px;
  border: 1.5px dashed var(--accent);
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  background: rgba(157,48,45,0.04);
  cursor: default;
  user-select: none;
}
.coming-soon-btn::before {
  content: '⏳';
  font-size: 0.85rem;
}

/* ===== SCHEDULE ===== */
.schedule-table {
  margin-top: 40px;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
  box-shadow: var(--shadow-sm);
}
.schedule-row {
  display: grid;
  grid-template-columns: 90px 1fr 90px;
  gap: 16px;
  padding: 14px 22px;
  background: rgba(255,255,255,0.58);
  border-bottom: 1px solid var(--line);
  font-size: 0.91rem;
  align-items: center;
}
.schedule-row:last-child { border-bottom: none; }
.schedule-row.header-row {
  background: var(--ink);
  color: #fff;
  font-weight: 700;
  font-size: 0.78rem;
  letter-spacing: 0.07em;
  text-transform: uppercase;
}
.schedule-row:nth-child(even):not(.header-row) { background: var(--paper-deep); }
.schedule-row span:first-child {
  font-weight: 700;
  color: var(--accent);
  font-size: 0.86rem;
  font-variant-numeric: tabular-nums;
}
.schedule-row.header-row span:first-child { color: rgba(255,255,255,0.70); }
.schedule-row span:last-child {
  color: var(--muted);
  font-size: 0.84rem;
  text-align: right;
}
.schedule-row.header-row span:last-child { color: rgba(255,255,255,0.70); }

/* ===== ORGANIZERS ===== */
.organizers-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 18px;
  margin-top: 40px;
}
.org-card {
  background: rgba(255,255,255,0.58);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 16px 16px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  text-align: center;
  transition: transform 0.18s, box-shadow 0.18s;
}
.org-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-sm); }

/* Photo placeholder — replace background with an <img> when photos are ready */
.org-photo {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: var(--paper-deep);
  border: 2px solid var(--line);
  flex-shrink: 0;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--muted);
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.04em;
}
.org-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 50%;
}

.org-card strong {
  font-size: 0.88rem;
  color: var(--ink);
  line-height: 1.3;
}
.org-card strong a {
  color: var(--ink);
  text-decoration: underline;
  text-decoration-color: rgba(45,95,157,0.35);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color 0.16s, text-decoration-color 0.16s;
}
.org-card strong a:hover {
  color: var(--blue);
  text-decoration-color: currentColor;
}
.org-card span { font-size: 0.76rem; color: var(--muted); line-height: 1.4; }

/* ===== CONTACT ===== */
.contact-container { }
.contact-lead {
  color: var(--muted);
  font-size: 0.97rem;
  margin: 8px 0 28px;
}
.contact-card {
  max-width: 480px;
}
.contact-card-inner {
  display: flex;
  align-items: center;
  gap: 20px;
  background: rgba(255,255,255,0.80);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px 24px;
  box-shadow: var(--shadow-sm);
}
.contact-avatar {
  width: 52px;
  height: 52px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-dark));
  color: #fff;
  font-weight: 800;
  font-size: 0.95rem;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.contact-name {
  font-size: 0.97rem;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 2px;
}
.contact-role {
  font-size: 0.82rem;
  color: var(--muted);
  margin-bottom: 6px;
}
.contact-email-link {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.16s;
}
.contact-email-link:hover {
  border-bottom-color: var(--accent);
}

/* ===== FOOTER ===== */
#footer {
  background: var(--ink);
  color: rgba(255,255,255,0.38);
  text-align: center;
  padding: 28px 24px;
  font-size: 0.84rem;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 900px) {
  .overview-grid { grid-template-columns: 1fr; }
  .challenge-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 600px) {
  .nav-links { display: none; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .schedule-row { grid-template-columns: 70px 1fr; }
  .schedule-row span:last-child { display: none; }
  .organizers-grid { grid-template-columns: 1fr 1fr; }
}