/* Base Styles */

:root {
  --ink: #111111;
  --ink-2: #333333;
  --ink-3: #666666;
  --paper: #FAF7F2;
  --paper-2: #F3EEE5;
  --rule: #EAE3D9;
  --rule-2: #DFD5C5;
  --accent: #C2410C;

  /* Ironbow thermal-camera palette — the site's signature accent motif,
     a nod to the conference's own subject matter (quantitative IR imaging) */
  --thermal-1: #0a0e27;
  --thermal-2: #3730a3;
  --thermal-3: #c026d3;
  --thermal-4: #dc2626;
  --thermal-5: #f97316;
  --thermal-6: #fde047;
  --thermal-gradient: linear-gradient(90deg,
    var(--thermal-1) 0%, var(--thermal-2) 22%, var(--thermal-3) 42%,
    var(--thermal-4) 60%, var(--thermal-5) 80%, var(--thermal-6) 100%);

  --max: 1200px;
  --gutter: 40px;

  --font-display: 'Cormorant Garamond', serif;
  --font-body: 'Inter', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-body);
  background-color: var(--paper);
  color: var(--ink);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  position: relative;
}

/* Subtle paper-grain texture for a tactile, printed feel */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 9999;
  pointer-events: none;
  opacity: 0.035;
  mix-blend-mode: multiply;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='120' height='120'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* Thermal gradient rule — used as a signature divider under the topbar
   and above the final CTA */
.thermal-rule {
  height: 3px;
  background: var(--thermal-gradient);
  background-size: 200% 100%;
  animation: thermal-drift 12s ease-in-out infinite;
}
@keyframes thermal-drift {
  0%, 100% { background-position: 0% 0; }
  50% { background-position: 100% 0; }
}

.thermal-text {
  background: var(--thermal-gradient);
  background-size: 200% 100%;
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* Scroll-reveal engine (see js/mobile-nav.js) */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 700ms cubic-bezier(0.16, 1, 0.3, 1), transform 700ms cubic-bezier(0.16, 1, 0.3, 1);
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
}

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

a.inline {
  border-bottom: 1px solid currentColor;
}

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

.wrap {
  width: 100%;
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

/* Sections */
.section-head {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  margin-bottom: 64px;
}

.section-head .eyebrow {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 16px;
}

.section-head h2 {
  font-family: var(--font-display);
  font-size: clamp(36px, 4.4vw, 56px);
  font-weight: 500;
  line-height: 1;
  letter-spacing: -0.015em;
}

.section-head .lede {
  font-size: 20px;
  color: var(--ink-2);
  line-height: 1.6;
}

/* Split content */
.split-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
}

/* Top bar */
.topbar {
  border-bottom: 1px solid var(--rule);
  padding: 20px 0;
  background: var(--paper);
  position: sticky;
  top: 0;
  z-index: 90;
}
.topbar::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: -1px;
  height: 3px;
  background: var(--thermal-gradient);
  background-size: 200% 100%;
  animation: thermal-drift 12s ease-in-out infinite;
}

.topbar-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 var(--gutter);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.brand {
  display: flex;
  align-items: center;
  gap: 16px;
  color: var(--ink);
}

.brand img {
  height: 40px;
  width: auto;
}

.brand-meta {
  display: flex;
  flex-direction: column;
}

.brand-meta strong {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 600;
  line-height: 1.1;
}

.brand-meta span {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.1em;
  color: var(--ink-3);
  text-transform: uppercase;
}

.nav {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav a {
  font-size: 14px;
  font-weight: 500;
  color: var(--ink-2);
  transition: color 150ms;
}

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

/* Dropdown nav group */
.nav-group {
  position: relative;
  display: flex;
  align-items: center;
}
.nav-group-head {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav-group .caret {
  font-size: 9px;
  color: var(--ink-3);
  transition: transform 150ms ease;
  display: inline-flex;
  padding: 4px;
  background: none;
  border: 0;
  cursor: pointer;
  line-height: 1;
}
.nav-group:hover .caret, .nav-group:focus-within .caret {
  transform: rotate(180deg);
}
.dropdown {
  position: absolute;
  top: 100%;
  left: -14px;
  min-width: 190px;
  background: var(--paper);
  border: 1px solid var(--rule);
  box-shadow: 0 16px 32px -14px rgba(17, 17, 17, 0.2);
  padding: 8px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(4px);
  transition: opacity 160ms ease, transform 160ms ease, visibility 160ms;
  z-index: 95;
}
.nav-group:hover .dropdown, .nav-group:focus-within .dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.dropdown a {
  display: block;
  padding: 9px 12px;
  font-size: 13px;
  border-radius: 3px;
}
.dropdown a:hover {
  background: var(--paper-2);
  color: var(--ink);
}
.dropdown a.active {
  color: var(--accent);
  font-weight: 600;
}

.top-cta .btn {
  font-size: 13px;
  padding: 10px 20px;
}

/* Base Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 28px;
  font-size: 15px;
  font-weight: 500;
  background: var(--accent);
  color: #fff;
  border: 1px solid var(--accent);
  border-radius: 4px;
  transition: transform 200ms ease, box-shadow 200ms ease, background 150ms ease, border-color 150ms ease;
  cursor: pointer;
}

.btn:hover {
  background: #A03308;
  border-color: #A03308;
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 10px 24px -8px rgba(194, 65, 12, 0.5);
}

.btn:active {
  transform: translateY(0);
  box-shadow: none;
}

.btn.ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--rule);
}

.btn.ghost:hover {
  background: var(--paper-2);
  border-color: var(--ink-3);
  box-shadow: 0 10px 24px -10px rgba(17, 17, 17, 0.18);
}

.btn .arrow {
  margin-left: 8px;
  transition: transform 150ms ease;
}

.btn:hover .arrow {
  transform: translateX(4px);
}

/* Typical page sections padding */
section {
  padding: 100px 0;
}

.mobile-menu-toggle {
  display: none;
}

@media (max-width: 960px) {
  .section-head, .split-2 {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .mobile-menu-toggle {
    display: block;
    background: none;
    border: none;
    color: var(--ink);
    font-size: 22px;
    cursor: pointer;
    padding: 4px;
    z-index: 110;
  }
  .topbar-inner {
    flex-wrap: wrap;
  }
  .nav {
    display: none;
    width: 100%;
    flex-direction: column;
    align-items: stretch;
    gap: 16px;
    padding: 24px 0 8px;
    border-top: 1px solid var(--rule);
    margin-top: 16px;
  }
  .topbar.menu-open .nav {
    display: flex;
  }
  .nav-group {
    flex-direction: column;
    align-items: stretch;
  }
  .nav-group-head {
    justify-content: space-between;
    width: 100%;
  }
  .dropdown {
    position: static;
    opacity: 1;
    visibility: visible;
    transform: none;
    box-shadow: none;
    border: 0;
    border-left: 2px solid var(--rule);
    background: none;
    padding: 4px 0 4px 14px;
    margin: 6px 0 0 4px;
    display: none;
  }
  .nav-group.mobile-open .dropdown {
    display: block;
  }
  .nav-group.mobile-open .caret {
    transform: rotate(180deg);
  }
  .topbar.menu-open .mobile-menu-toggle i::before {
    content: "\f00d"; /* FontAwesome times (X) icon */
  }
  .top-cta {
    display: none;
  }
}

/* ===== Footer organiser logos (shared across all pages) ===== */
.footer-orgs {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  gap: 72px;
  flex-wrap: wrap;
  padding: 44px 0 40px;
  border-top: 1px solid var(--rule);
}
.footer-org {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
}
.footer-org .org-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-3);
}
.footer-org img {
  height: 52px;
  width: auto;
  max-width: 240px;
  object-fit: contain;
  display: block;
}
.foot-legal {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 24px 0;
  border-top: 1px solid var(--rule);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--ink-3);
}
@media (max-width: 600px) {
  .footer-orgs { gap: 40px; padding: 32px 0; }
  .footer-org img { height: 42px; }
  .foot-legal { flex-direction: column; gap: 10px; text-align: center; }
}