/* ============================================================================
   IJCIEOM 2027 — STYLES
   Palette: deep ocean navy (intelligent/digital) + regenerative emerald
   + a warm Rio coral accent. Light, airy, professional/academic.
   You rarely need to edit this file; content lives in the pages + site.js.
   ============================================================================ */

:root {
  --navy-900: #0a1f3c;
  --navy-800: #0e2a52;
  --navy-700: #143a6b;
  --navy-600: #1d4f8a;
  --emerald: #14a37f;
  --emerald-600: #0e8a6a;
  --emerald-50: #e7f7f1;
  --coral: #ff6b5e;
  --coral-600: #ec5646;
  --amber: #f5a524;

  --ink: #10233d;
  --body: #3a4a60;
  --muted: #6b7a90;
  --line: #e3e8ef;
  --bg: #ffffff;
  --bg-soft: #f5f8fc;
  --bg-tint: #eef4fb;

  --radius: 16px;
  --radius-sm: 10px;
  --shadow-sm: 0 2px 10px rgba(16, 35, 61, 0.06);
  --shadow: 0 12px 40px rgba(16, 35, 61, 0.10);
  --shadow-lg: 0 24px 70px rgba(16, 35, 61, 0.16);

  --font-head: 'Space Grotesk', 'Segoe UI', system-ui, sans-serif;
  --font-body: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;

  --maxw: 1160px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--body);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

h1, h2, h3, h4 {
  font-family: var(--font-head);
  color: var(--ink);
  line-height: 1.12;
  margin: 0 0 0.5em;
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(2.1rem, 5vw, 3.6rem); font-weight: 600; }
h2 { font-size: clamp(1.6rem, 3.4vw, 2.5rem); font-weight: 600; }
h3 { font-size: clamp(1.15rem, 2vw, 1.4rem); font-weight: 600; }

p { margin: 0 0 1.1rem; }

a { color: var(--navy-600); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--emerald-600); }

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

.container { width: min(var(--maxw), 92%); margin: 0 auto; }

.section { padding: clamp(3.5rem, 8vw, 6.5rem) 0; }
.section-tint { background: var(--bg-soft); }
.section-navy {
  background: linear-gradient(160deg, var(--navy-900), var(--navy-700));
  color: #cfe0f5;
}
.section-navy h2, .section-navy h3 { color: #fff; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-head);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--emerald-600);
  margin-bottom: 1rem;
}
.eyebrow::before {
  content: '';
  width: 26px; height: 2px;
  background: var(--emerald);
  border-radius: 2px;
}
.section-navy .eyebrow { color: #6fe3c2; }
.section-navy .eyebrow::before { background: #6fe3c2; }

.lead { font-size: 1.18rem; color: var(--muted); max-width: 46ch; }
.section-navy .lead { color: #b7ccea; }

/* ---------------------------------------------------------------- Buttons -- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 0.98rem;
  padding: 0.85rem 1.5rem;
  border-radius: 999px;
  background: var(--emerald);
  color: #fff;
  border: 1.5px solid var(--emerald);
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.2s, background 0.2s;
  box-shadow: 0 8px 22px rgba(20, 163, 127, 0.28);
}
.btn:hover { background: var(--emerald-600); color: #fff; transform: translateY(-2px); }
.btn-sm { padding: 0.55rem 1.1rem; font-size: 0.88rem; box-shadow: none; }
.btn-outline {
  background: transparent;
  color: var(--ink);
  border-color: var(--line);
  box-shadow: none;
}
.btn-outline:hover { background: var(--bg-tint); color: var(--navy-700); border-color: var(--navy-600); }
.btn-ghost-light {
  background: rgba(255,255,255,0.08);
  border-color: rgba(255,255,255,0.35);
  color: #fff;
  box-shadow: none;
}
.btn-ghost-light:hover { background: rgba(255,255,255,0.16); color:#fff; }
.btn-coral { background: var(--coral); border-color: var(--coral); box-shadow: 0 8px 22px rgba(255,107,94,0.3); }
.btn-coral:hover { background: var(--coral-600); }

.btn-row { display: flex; flex-wrap: wrap; gap: 0.9rem; margin-top: 1.6rem; }

/* --------------------------------------------------------------- Navbar --- */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,0.85);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 74px; }

.brand { display: inline-flex; align-items: center; }
.logo-lockup { display: inline-flex; align-items: center; gap: 0.62rem; }
.logo-mark-img { height: 44px; width: auto; display: block; }
.logo-text { display: flex; flex-direction: column; line-height: 1.05; }
.logo-acr { font-family: var(--font-head); font-weight: 700; font-size: 1.28rem; color: #0b1f51; letter-spacing: 0.01em; }
.logo-year { font-family: var(--font-head); font-weight: 600; font-size: 0.7rem; letter-spacing: 0.14em; color: var(--emerald-600); text-transform: uppercase; margin-top: 2px; }
.footer .logo-acr { color: #fff; }
.footer .logo-year { color: #6fe3c2; }
.footer .logo-mark-img { height: 48px; }
.logo-img { height: 48px; width: auto; }

.nav-menu { display: flex; align-items: center; gap: 1.2rem; }
.nav-menu ul { display: flex; align-items: center; gap: 1.05rem; list-style: none; margin: 0; padding: 0; }
.nav-menu a { font-size: 0.92rem; font-weight: 500; color: var(--body); position: relative; white-space: nowrap; }
.nav-menu a:hover, .nav-menu a.active { color: var(--navy-700); }
.nav-menu a.active::after {
  content: ''; position: absolute; left: 0; right: 0; bottom: -6px; height: 2px;
  background: var(--emerald); border-radius: 2px;
}
.soon-badge {
  font-family: var(--font-head);
  font-size: 0.58rem; font-weight: 600; letter-spacing: 0.06em; text-transform: uppercase;
  color: var(--amber); background: rgba(245,165,36,0.14);
  padding: 1px 6px; border-radius: 999px; margin-left: 5px; vertical-align: middle;
}
.nav-cta { white-space: nowrap; }

.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: none; cursor: pointer; padding: 8px; }
.nav-toggle span { width: 24px; height: 2px; background: var(--ink); border-radius: 2px; transition: 0.25s; }

/* --------------------------------------------------------------- Hero ----- */
.hero {
  position: relative;
  color: #eaf2ff;
  /* Rio de Janeiro hero photo (assets/hero-rio.jpg) with a dark overlay for legibility.
     To swap the photo, replace assets/hero-rio.jpg (or edit the url below). */
  background:
    linear-gradient(105deg, rgba(6,17,34,0.94) 0%, rgba(9,28,56,0.86) 34%, rgba(11,40,74,0.60) 62%, rgba(16,58,96,0.32) 100%),
    url('hero-rio.jpg');
  background-size: cover;
  background-position: center 32%;
  overflow: hidden;
  padding: clamp(3.5rem, 8vw, 6rem) 0 clamp(3rem, 6vw, 5rem);
}
.hero::before {
  content: '';
  position: absolute; inset: 0;
  background:
    linear-gradient(to top, rgba(6,17,34,0.85) 0%, rgba(6,17,34,0.0) 42%),
    radial-gradient(circle at 88% 82%, rgba(20,163,127,0.28), transparent 46%);
  pointer-events: none;
}
.hero-grid {
  position: absolute; inset: 0; opacity: 0.28;
  background-image:
    linear-gradient(rgba(255,255,255,0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.05) 1px, transparent 1px);
  background-size: 54px 54px;
  mask-image: radial-gradient(circle at 20% 30%, #000, transparent 70%);
  pointer-events: none;
}
.hero .container { position: relative; z-index: 2; }
.hero-badge {
  display: inline-flex; align-items: center; gap: 0.6rem;
  background: rgba(255,255,255,0.10);
  border: 1px solid rgba(255,255,255,0.22);
  padding: 0.4rem 0.95rem; border-radius: 999px;
  font-family: var(--font-head); font-size: 0.82rem; letter-spacing: 0.02em; color: #d7e6ff;
  margin-bottom: 1.5rem;
}
.hero-badge .pulse { width: 8px; height: 8px; border-radius: 50%; background: var(--emerald); box-shadow: 0 0 0 0 rgba(20,163,127,0.7); animation: pulse 2s infinite; }
@keyframes pulse { 0% { box-shadow: 0 0 0 0 rgba(20,163,127,0.6);} 70%{ box-shadow: 0 0 0 10px rgba(20,163,127,0);} 100%{ box-shadow:0 0 0 0 rgba(20,163,127,0);} }

.hero-logo { display: flex; flex-direction: column; align-items: flex-start; gap: 0.5rem; margin-bottom: 1.4rem; }
.hero-logo-mark { height: clamp(64px, 9vw, 96px); width: auto; filter: drop-shadow(0 6px 22px rgba(0,0,0,0.35)); }
.hero-logo-word { height: clamp(30px, 4.4vw, 48px); width: auto; filter: drop-shadow(0 2px 14px rgba(0,0,0,0.4)); }
.hero-logo-ed { font-family: var(--font-head); font-weight: 600; font-size: clamp(0.78rem, 1.4vw, 0.95rem); letter-spacing: 0.16em; text-transform: uppercase; color: #6fe3c2; }
.hero-logo-ed sup { font-size: 0.62em; }

.hero h1 { color: #fff; max-width: 16ch; text-shadow: 0 2px 24px rgba(4,12,26,0.55); }
.hero h1 .accent { background: linear-gradient(90deg, #6fe3c2, #8fd8ff); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero-theme { font-size: clamp(1.05rem, 2vw, 1.3rem); color: #d3e2f7; max-width: 52ch; margin-top: 0.4rem; text-shadow: 0 1px 14px rgba(4,12,26,0.5); }

.hero-meta { display: flex; flex-wrap: wrap; gap: 1.6rem; margin: 2rem 0 0; }
.hero-meta .hm { display: flex; align-items: center; gap: 0.7rem; }
.hero-meta .hm-ico {
  width: 42px; height: 42px; border-radius: 12px; display: grid; place-items: center;
  background: rgba(255,255,255,0.10); border: 1px solid rgba(255,255,255,0.18); font-size: 1.2rem;
}
.hero-meta .hm-t { font-family: var(--font-head); font-weight: 600; color: #fff; font-size: 1.02rem; }
.hero-meta .hm-s { font-size: 0.82rem; color: #9fb8dd; }

/* Countdown */
.countdown { display: flex; gap: 0.8rem; margin-top: 2.4rem; flex-wrap: wrap; }
.cd-unit {
  min-width: 78px; text-align: center;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.16);
  border-radius: var(--radius-sm);
  padding: 0.9rem 0.6rem;
  backdrop-filter: blur(6px);
}
.cd-num { display: block; font-family: var(--font-head); font-weight: 700; font-size: 1.9rem; color: #fff; font-variant-numeric: tabular-nums; }
.cd-label { font-size: 0.72rem; letter-spacing: 0.14em; text-transform: uppercase; color: #9fb8dd; }
.cd-live { font-family: var(--font-head); font-size: 1.2rem; color: #6fe3c2; }

/* --------------------------------------------------------------- Cards ---- */
.grid { display: grid; gap: 1.4rem; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.7rem;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: #d3ddea; }
.card .card-ico {
  width: 50px; height: 50px; border-radius: 13px; display: grid; place-items: center;
  font-size: 1.5rem; margin-bottom: 1rem;
  background: var(--emerald-50); color: var(--emerald-600);
}
.card h3 { margin-bottom: 0.4rem; }
.card p { color: var(--muted); font-size: 0.96rem; margin: 0; }

/* Guest editor avatar + topic lists (Call for Papers) */
.editor-av { width: 54px; height: 54px; border-radius: 50%; background: var(--emerald-50); color: var(--emerald-600); display: grid; place-items: center; font-family: var(--font-head); font-weight: 700; font-size: 1.05rem; margin-bottom: 1rem; }
.editor-card h3 { margin-bottom: 0.15rem; }
.editor-aff { font-family: var(--font-head); font-weight: 600; font-size: 0.9rem; color: var(--emerald-600); margin-bottom: 0.6rem; }
.editor-card p { color: var(--muted); font-size: 0.92rem; }
.topic-list { list-style: none; margin: 0.7rem 0 0; padding: 0; }
.topic-list li { position: relative; padding-left: 1.15rem; margin-bottom: 0.5rem; font-size: 0.93rem; color: var(--muted); line-height: 1.5; }
.topic-list li::before { content: ''; position: absolute; left: 0; top: 0.55em; width: 6px; height: 6px; border-radius: 50%; background: var(--emerald); }
.cfp-facts { align-self: start; }
.cfp-facts .date-hi { display: block; font-family: var(--font-head); font-weight: 700; font-size: 1.5rem; color: var(--coral-600); }

/* Line icons (SVG) */
.card-ico svg { width: 26px; height: 26px; }
.hm-ico { color: #dbe8fb; }
.hm-ico svg { width: 22px; height: 22px; }
.soon-icon svg { width: 42px; height: 42px; }

/* Split feature */
.split { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: clamp(2rem, 5vw, 4rem); align-items: center; }

/* Photo card (real imagery) */
.photo-card { position: relative; margin: 0; border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); aspect-ratio: 16 / 11; }
.photo-card img { width: 100%; height: 100%; object-fit: cover; display: block; transition: transform 0.6s ease; }
.photo-card:hover img { transform: scale(1.05); }
.photo-card figcaption {
  position: absolute; left: 0; right: 0; bottom: 0;
  display: flex; flex-direction: column; gap: 2px;
  padding: 1.6rem 1.4rem 1.2rem; color: #fff;
  background: linear-gradient(to top, rgba(6,17,34,0.85), transparent);
}
.photo-card .pc-title { font-family: var(--font-head); font-weight: 600; font-size: 1.35rem; }
.photo-card .pc-sub { font-size: 0.9rem; color: #d7e6ff; opacity: 0.92; }

/* Stat strip */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.2rem; }
.stat { text-align: center; padding: 1rem; }
.stat .num { font-family: var(--font-head); font-weight: 700; font-size: clamp(1.8rem, 4vw, 2.6rem); color: #fff; }
.stat .lbl { font-size: 0.85rem; color: #9fb8dd; letter-spacing: 0.02em; }

/* Important dates */
.dates-wrap { border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow-sm); background: #fff; }
.date-row { display: flex; justify-content: space-between; align-items: center; gap: 1rem; padding: 1.05rem 1.5rem; border-bottom: 1px solid var(--line); }
.date-row:last-child { border-bottom: none; }
.date-label { font-weight: 500; color: var(--ink); }
.date-value { font-family: var(--font-head); font-weight: 600; font-size: 0.95rem; }
.date-confirmed { background: linear-gradient(90deg, var(--emerald-50), transparent); }
.date-confirmed .date-value { color: var(--emerald-600); }
.date-tbc .date-value { color: var(--amber); font-weight: 500; font-family: var(--font-body); font-style: italic; }

/* Tracks */
.tracks { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(2, 1fr); gap: 0.7rem; }
.tracks li { display: flex; align-items: center; gap: 0.9rem; padding: 0.95rem 1.1rem; background: #fff; border: 1px solid var(--line); border-radius: var(--radius-sm); font-weight: 500; color: var(--ink); transition: 0.2s; }
.tracks li:hover { border-color: var(--emerald); box-shadow: var(--shadow-sm); }
.track-num { font-family: var(--font-head); font-weight: 700; color: var(--emerald); font-size: 0.85rem; }

/* Pills / chips */
.chips { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-top: 1rem; }
.chip { font-size: 0.85rem; padding: 0.35rem 0.85rem; border-radius: 999px; background: var(--bg-tint); color: var(--navy-700); font-weight: 500; }

/* --------------------------------------------------------------- Coming soon */
.soon-hero { text-align: center; padding: clamp(3rem, 7vw, 5rem) 0 clamp(2rem, 4vw, 3rem); }
.soon-icon {
  width: 84px; height: 84px; border-radius: 22px; margin: 0 auto 1.6rem;
  display: grid; place-items: center; font-size: 2.4rem;
  background: linear-gradient(135deg, var(--navy-800), var(--navy-600)); color: #fff;
  box-shadow: var(--shadow);
}
.soon-tag {
  display: inline-block; font-family: var(--font-head); font-weight: 600;
  letter-spacing: 0.14em; text-transform: uppercase; font-size: 0.78rem;
  color: var(--amber); background: rgba(245,165,36,0.14); padding: 0.35rem 1rem; border-radius: 999px; margin-bottom: 1.2rem;
}
.soon-body { max-width: 640px; margin: 0 auto; text-align: center; }
.notify-box {
  margin-top: 2.4rem; padding: 1.8rem; border-radius: var(--radius);
  background: var(--bg-soft); border: 1px solid var(--line);
}

/* Info list (venue etc.) */
.info-list { list-style: none; margin: 1.2rem 0 0; padding: 0; }
.info-list li { display: flex; gap: 0.9rem; padding: 0.7rem 0; border-bottom: 1px dashed var(--line); }
.info-list li:last-child { border-bottom: none; }
.info-list .k { font-family: var(--font-head); font-weight: 600; color: var(--ink); min-width: 130px; }
.info-list .v { color: var(--body); }

.map-frame { width: 100%; border: 0; border-radius: var(--radius); min-height: 340px; box-shadow: var(--shadow-sm); }

/* Contact */
.contact-card { text-align: center; }
.contact-card .big-mail { font-family: var(--font-head); font-size: clamp(1.1rem, 3vw, 1.6rem); font-weight: 600; color: var(--navy-700); word-break: break-word; }

/* Page header (interior pages) */
.page-head {
  background: linear-gradient(155deg, var(--navy-900), var(--navy-700));
  color: #dbe8fb; padding: clamp(2.6rem, 6vw, 4rem) 0 clamp(2.2rem, 5vw, 3.2rem);
  position: relative; overflow: hidden;
}
.page-head::after {
  content: ''; position: absolute; inset: 0;
  background: radial-gradient(circle at 85% 20%, rgba(20,163,127,0.35), transparent 45%),
              radial-gradient(circle at 10% 90%, rgba(255,107,94,0.22), transparent 50%);
}
.page-head .container { position: relative; z-index: 2; }
.page-head h1 { color: #fff; margin-bottom: 0.5rem; }
.page-head .crumb { font-size: 0.85rem; color: #9fb8dd; }
.page-head .crumb a { color: #9fb8dd; }
.page-head .crumb a:hover { color: #fff; }

/* --------------------------------------------------------------- Footer --- */
.footer { background: var(--navy-900); color: #a9bfe0; padding: 3.5rem 0 1.6rem; }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1.3fr 1.3fr; gap: 2rem; }
.footer-brand .logo-lockup { margin-bottom: 1rem; }
.footer-theme { color: #cbd8ee; font-weight: 500; max-width: 30ch; }
.footer-meta { font-size: 0.88rem; color: #7f97bd; }
.footer-col h4 { color: #fff; font-size: 0.82rem; letter-spacing: 0.12em; text-transform: uppercase; margin-bottom: 1rem; }
.footer-col ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 0.55rem; font-size: 0.92rem; }
.footer-col a { color: #a9bfe0; }
.footer-col a:hover { color: #6fe3c2; }
.footer-bottom {
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 0.6rem;
  border-top: 1px solid rgba(255,255,255,0.10); margin-top: 2.6rem; padding-top: 1.4rem;
  font-size: 0.82rem; color: #7f97bd;
}

/* --------------------------------------------------------------- Reveal --- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal.in { opacity: 1; transform: none; }

/* --------------------------------------------------------------- Utilities */
.text-center { text-align: center; }
.mx-auto { margin-left: auto; margin-right: auto; }
.mt-0 { margin-top: 0; }
.section-head { max-width: 640px; margin-bottom: 2.6rem; }
.section-head.center { margin-left: auto; margin-right: auto; text-align: center; }

/* --------------------------------------------------------------- Responsive */
@media (max-width: 1040px) {
  .nav-menu { gap: 0; }
  .nav-toggle { display: flex; }
  .nav-menu {
    position: fixed; inset: 74px 0 auto 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: #fff; border-bottom: 1px solid var(--line);
    padding: 0.5rem 6% 1.4rem; box-shadow: var(--shadow);
    transform: translateY(-120%); transition: transform 0.3s ease;
  }
  .nav.open .nav-menu { transform: translateY(0); }
  .nav-menu ul { flex-direction: column; align-items: stretch; gap: 0; width: 100%; }
  .nav-menu li { border-bottom: 1px solid var(--line); }
  .nav-menu ul a { display: block; padding: 0.95rem 0.2rem; font-size: 1rem; }
  .nav-menu a.active::after { display: none; }
  .nav-cta { margin-top: 1rem; text-align: center; justify-content: center; }
}

@media (max-width: 900px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .split { grid-template-columns: 1fr; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .tracks { grid-template-columns: 1fr; }
}

@media (max-width: 560px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .hero-meta { gap: 1rem; }
  .cd-unit { min-width: 66px; }
}

/* --------------------------------------------------------------- Dark mode -
   The site is intentionally light (matching the academic 2026 identity),
   but we keep text legible if a device forces dark rendering of form controls. */
@media (prefers-color-scheme: dark) {
  /* No global inversion — the brand is light. Left intentionally minimal. */
}