/* ==========================================================================
   ICIEURS 2026  —  Shared stylesheet
   Theme: an ocean "descent" — surface light fading into the abyss.
   Edit COLORS/FONTS only inside :root below if you want to re-skin the site.
   ========================================================================== */

/* ---- Design tokens ------------------------------------------------------ */
:root{
  /* Palette: deep-sea gradient + one bioluminescent accent */
  --abyss:    #071a3d;   /* page background (deepest) */
  --deep:     #0c2452;   /* section background */
  --deep-2:   #143066;   /* raised cards */
  --current:  #2056ab;   /* mid-water teal */
  --glow:     #4d9bff;   /* SIGNATURE bioluminescent accent */
  --glow-2:   #74b2ff;   /* brighter glow for hovers */
  --coral:    #ff7a66;   /* used VERY sparingly: live deadline / urgency */
  --foam:     #eef3fc;   /* headings / brightest text */
  --mist:     #b1c2de;   /* body text */
  --mist-dim: #7083a6;   /* captions, meta, depth labels */
  --line:     rgba(177,194,222,.14);   /* hairline borders */
  --glow-haze:rgba(77,155,255,.14);    /* soft accent fills */

  /* Type */
  --font-display: "Sora", system-ui, sans-serif;
  --font-body:    "IBM Plex Sans", system-ui, sans-serif;
  --font-mono:    "IBM Plex Mono", ui-monospace, monospace;

  /* Layout */
  --max: 1120px;
  --gutter: clamp(20px, 5vw, 64px);
  --radius: 14px;
  --nav-h: 68px;
}

/* ---- Reset / base ------------------------------------------------------- */
*{ box-sizing: border-box; }
html{ scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body{
  margin: 0;
  background: var(--abyss);
  color: var(--mist);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.7;
  letter-spacing: .005em;
  overflow-x: hidden;
}
img{ max-width: 100%; display: block; }
a{ color: var(--glow); text-decoration: none; transition: color .2s ease; }
a:hover{ color: var(--glow-2); }
h1,h2,h3,h4{ font-family: var(--font-display); color: var(--foam); line-height: 1.12; margin: 0 0 .4em; font-weight: 600; }
p{ margin: 0 0 1.1em; }
::selection{ background: var(--glow); color: var(--abyss); }

/* Visible keyboard focus (accessibility floor) */
a:focus-visible, button:focus-visible{
  outline: 2px solid var(--glow);
  outline-offset: 3px;
  border-radius: 4px;
}

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

/* ---- Navigation --------------------------------------------------------- */
.nav{
  position: sticky; top: 0; z-index: 50;
  height: var(--nav-h);
  display: flex; align-items: center;
  background: rgba(7,26,61,.72);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}
.nav .wrap{ display: flex; align-items: center; justify-content: space-between; width: 100%; }
.brand{ display: flex; align-items: center; gap: 11px; color: var(--foam); font-family: var(--font-display); font-weight: 700; font-size: 19px; letter-spacing: .02em; }
.brand svg{ width: 30px; height: 30px; flex: none; }
.brand small{ display: block; font-family: var(--font-mono); font-size: 10px; font-weight: 400; letter-spacing: .22em; color: var(--mist-dim); margin-top: 1px; }

.nav-links{ display: flex; align-items: center; gap: 2px; list-style: none; margin: 0; padding: 0; flex-wrap: nowrap; }
.nav-links a{
  color: var(--mist); font-size: 14px; font-weight: 500;
  padding: 9px 12px; border-radius: 8px; letter-spacing: .01em; white-space: nowrap;
}
.nav-links a:hover{ color: var(--foam); background: rgba(255,255,255,.04); }
.nav-links a.active{ color: var(--glow); }
.nav-links .cta-link{
  margin-left: 12px; background: var(--glow); color: var(--abyss); font-weight: 600;
}
.nav-links .cta-link:hover{ background: var(--glow-2); color: var(--abyss); }

.nav-toggle{
  display: none; background: none; border: 1px solid var(--line); border-radius: 9px;
  width: 42px; height: 38px; cursor: pointer; padding: 0;
}
.nav-toggle span{ display: block; width: 18px; height: 2px; background: var(--foam); margin: 4px auto; transition: .25s; }

/* ---- Buttons ------------------------------------------------------------ */
.btn{
  display: inline-flex; align-items: center; gap: 9px;
  font-family: var(--font-body); font-weight: 600; font-size: 15px;
  padding: 13px 22px; border-radius: 999px; cursor: pointer;
  border: 1px solid transparent; transition: transform .15s ease, box-shadow .25s ease, background .2s ease;
}
.btn-primary{ background: var(--glow); color: var(--abyss); box-shadow: 0 0 0 rgba(77,155,255,0); }
.btn-primary:hover{ background: var(--glow-2); color: var(--abyss); transform: translateY(-2px); box-shadow: 0 12px 40px -8px var(--glow); }
.btn-ghost{ background: transparent; color: var(--foam); border-color: var(--line); }
.btn-ghost:hover{ border-color: var(--glow); color: var(--glow); transform: translateY(-2px); }

/* ---- Section scaffolding ------------------------------------------------ */
.section{ padding: clamp(64px, 9vw, 120px) 0; position: relative; }
.section--deep{ background: var(--deep); }
.eyebrow{
  font-family: var(--font-mono); font-size: 12px; letter-spacing: .26em; text-transform: uppercase;
  color: var(--glow); margin-bottom: 14px; display: flex; align-items: center; gap: 12px;
}
.eyebrow::before{ content: ""; width: 26px; height: 1px; background: var(--glow); display: inline-block; }
.section-title{ font-size: clamp(28px, 4.5vw, 46px); max-width: 16ch; margin-bottom: .5em; }
.lead{ font-size: clamp(17px, 2vw, 20px); color: var(--mist); max-width: 62ch; }

/* Justified body prose (used only on About / CFP content paragraphs).
   Hyphenation is enabled so justification doesn't create large word gaps. */
.prose{ text-align: justify; text-justify: inter-word; -webkit-hyphens: auto; -ms-hyphens: auto; hyphens: auto; }

/* ---- Hero --------------------------------------------------------------- */
.hero{ position: relative; min-height: auto; display: flex; align-items: center; overflow: hidden;
  background:
    radial-gradient(120% 90% at 50% -10%, rgba(77,155,255,.10), transparent 55%),
    linear-gradient(180deg, #0d2a5e 0%, var(--abyss) 70%); }
.hero .wrap{ position: relative; z-index: 3; padding-top: 48px; padding-bottom: 64px; }
.hero-tag{ font-family: var(--font-mono); font-size: 13px; letter-spacing: .2em; color: var(--glow); text-transform: uppercase; margin-bottom: 20px; }
.hero h1{ font-size: clamp(32px, 6vw, 64px); letter-spacing: -.02em; margin-bottom: .25em; }
.hero h1 .sub{ display: block; font-size: clamp(15px, 2.4vw, 22px); font-weight: 400; color: var(--mist); letter-spacing: .01em; margin-top: 14px; max-width: 30ch; line-height: 1.4; }
.hero-meta{ display: flex; flex-wrap: wrap; gap: 12px 28px; margin: 22px 0 26px; font-family: var(--font-mono); font-size: 14px; color: var(--mist); }
.hero-meta b{ color: var(--foam); font-weight: 600; }
.hero-actions{ display: flex; flex-wrap: wrap; gap: 14px; }

/* Sonar ping signature — rings are anchored to the AUV nose and travel with it.
   Three transform layers so animations never fight:
   .auv-track = vertical centering · .auv-wrap = horizontal drift · .auv = bob */
.sonar{ position: absolute; inset: 0; z-index: 1; pointer-events: none; }
.auv-track{ position: absolute; top: 50%; right: 5%; transform: translateY(-50%); }
.auv-wrap{ position: relative; animation: auv-drift 26s ease-in-out infinite; }
.auv{ width: clamp(150px, 17vw, 250px); height: auto; display: block;
  filter: drop-shadow(0 0 20px rgba(77,155,255,.20)); animation: auv-float 6.5s ease-in-out infinite; }
.auv-eye{ animation: auv-pulse 2.4s ease-in-out infinite; transform-origin: 221px 60px; }

.ping{ position: absolute; top: 50%; right: 16px; width: 16px; height: 16px; margin: -8px -8px 0 0;
  border-radius: 50%; border: 1px solid var(--glow); opacity: 0; animation: ping 5s ease-out infinite; }
.ping:nth-child(2){ animation-delay: 1.7s; }
.ping:nth-child(3){ animation-delay: 3.4s; }

@keyframes ping{ 0%{ transform: scale(1); opacity: .9; } 100%{ transform: scale(34); opacity: 0; } }
@keyframes auv-drift{ 0%,100%{ transform: translateX(0); } 50%{ transform: translateX(-78px); } }
@keyframes auv-float{ 0%,100%{ transform: translateY(-6px) rotate(-1.2deg); } 50%{ transform: translateY(6px) rotate(1.2deg); } }
@keyframes auv-pulse{ 0%,100%{ opacity: 1; } 50%{ opacity: .35; } }

/* faint horizontal "current" lines drifting */
.hero-lines{ position: absolute; inset: 0; z-index: 1; opacity: .35;
  background-image: repeating-linear-gradient(0deg, transparent 0 38px, rgba(177,194,222,.05) 38px 39px); }

/* Countdown */
.countdown{ display: flex; gap: 10px; margin-top: 6px; }
.cd-cell{ background: rgba(255,255,255,.03); border: 1px solid var(--line); border-radius: 12px; padding: 12px 16px; min-width: 72px; text-align: center; }
.cd-cell b{ display: block; font-family: var(--font-mono); font-size: 26px; color: var(--foam); font-weight: 600; line-height: 1; }
.cd-cell span{ font-family: var(--font-mono); font-size: 10px; letter-spacing: .18em; text-transform: uppercase; color: var(--mist-dim); }

/* ---- Cards & grids ------------------------------------------------------ */
.grid{ display: grid; gap: 20px; }
.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(--deep-2); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 28px; transition: transform .25s ease, border-color .25s ease, box-shadow .25s ease;
}
.card:hover{ transform: translateY(-4px); border-color: rgba(77,155,255,.4); box-shadow: 0 20px 50px -24px rgba(0,0,0,.8); }
.card h3{ font-size: 21px; }
.card .num{ font-family: var(--font-mono); font-size: 12px; color: var(--glow); letter-spacing: .2em; }

/* Theme (depth-zone) cards */
.zone{ position: relative; overflow: hidden; }
.zone .depth{ font-family: var(--font-mono); font-size: 11px; letter-spacing: .18em; color: var(--mist-dim); text-transform: uppercase; }
.zone ul{ margin: 14px 0 0; padding-left: 18px; color: var(--mist); font-size: 15px; }
.zone ul li{ margin-bottom: 6px; }
.zone ul li::marker{ color: var(--glow); }

/* ---- Timeline (Important Dates) ---------------------------------------- */
.timeline{ list-style: none; margin: 0; padding: 0; position: relative; max-width: 760px; }
.timeline::before{ content: ""; position: absolute; left: 13px; top: 8px; bottom: 8px; width: 2px;
  background: linear-gradient(180deg, var(--glow), var(--current)); }
.timeline li{ position: relative; padding: 0 0 30px 52px; }
.timeline li::before{ content: ""; position: absolute; left: 6px; top: 4px; width: 16px; height: 16px;
  border-radius: 50%; background: var(--abyss); border: 2px solid var(--glow); }
.timeline li.is-live::before{ background: var(--coral); border-color: var(--coral); box-shadow: 0 0 14px 2px var(--coral); }
.timeline .date{ font-family: var(--font-mono); font-size: 13px; color: var(--glow); letter-spacing: .06em; }
.timeline .label{ color: var(--foam); font-weight: 600; font-family: var(--font-display); font-size: 18px; }

/* ---- Tables (fees) ------------------------------------------------------ */
.table-wrap{ overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); }
table.fees{ width: 100%; border-collapse: collapse; font-size: 15px; min-width: 460px; }
table.fees th, table.fees td{ padding: 15px 20px; text-align: left; border-bottom: 1px solid var(--line); }
table.fees thead th{ font-family: var(--font-mono); font-size: 12px; letter-spacing: .14em; text-transform: uppercase; color: var(--glow); background: rgba(77,155,255,.05); }
table.fees tbody tr:hover{ background: rgba(255,255,255,.025); }
table.fees td:not(:first-child){ font-family: var(--font-mono); color: var(--foam); }

/* ---- Stat / fact strip -------------------------------------------------- */
.facts{ display: grid; grid-template-columns: repeat(4,1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
.facts div{ background: var(--deep); padding: 26px 22px; }
.facts b{ display: block; font-family: var(--font-display); font-size: clamp(26px,3vw,38px); color: var(--glow); }
.facts span{ font-size: 13px; color: var(--mist-dim); font-family: var(--font-mono); letter-spacing: .08em; }
/* Highlights strip placed inside the hero */
.hero .facts{ margin-top: 32px; background: var(--line); }
.hero .facts div{ background: rgba(13,42,94,.7); padding: 18px 20px; }

/* ---- People (committees / speakers) ------------------------------------ */
.person{ text-align: center; }
.person .avatar{ width: 96px; height: 96px; border-radius: 50%; margin: 0 auto 14px; object-fit: cover;
  background: linear-gradient(135deg, var(--current), var(--glow)); border: 1px solid var(--line);
  display: flex; align-items: center; justify-content: center; font-family: var(--font-display); font-size: 30px; color: var(--abyss); font-weight: 700; }
.person h4{ font-size: 18px; margin-bottom: 2px; }
.person .role{ font-size: 14px; color: var(--mist); }
.person .org{ font-size: 13px; color: var(--mist-dim); font-family: var(--font-mono); }

/* Speaker (wide) */
.speaker{ display: grid; grid-template-columns: 180px 1fr; gap: 30px; align-items: start; }
.speaker .avatar{ width: 180px; height: 180px; border-radius: 16px; font-size: 56px; }
.speaker p{ font-size: 15.5px; }

/* ---- Two-column prose --------------------------------------------------- */
.cols-2{ display: grid; grid-template-columns: 1fr 1fr; gap: clamp(28px,5vw,64px); align-items: start; }

/* ---- Footer ------------------------------------------------------------- */
.footer{ background: #050f2c; border-top: 1px solid var(--line); padding: 60px 0 34px; }
.footer .grid-foot{ display: grid; grid-template-columns: 1.6fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer h5{ font-family: var(--font-mono); font-size: 12px; letter-spacing: .2em; text-transform: uppercase; color: var(--mist-dim); margin: 0 0 16px; }
.footer ul{ list-style: none; padding: 0; margin: 0; }
.footer ul li{ margin-bottom: 9px; }
.footer ul a{ color: var(--mist); font-size: 15px; }
.footer ul a:hover{ color: var(--glow); }
.footer .copy{ border-top: 1px solid var(--line); padding-top: 22px; font-size: 13px; color: var(--mist-dim); font-family: var(--font-mono); display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px; }

/* ---- Page header (inner pages) ----------------------------------------- */
.page-head{ padding: clamp(54px,8vw,96px) 0 clamp(30px,4vw,44px);
  background: radial-gradient(110% 120% at 80% -20%, rgba(77,155,255,.10), transparent 50%), var(--deep); border-bottom: 1px solid var(--line); }
.page-head h1{ font-size: clamp(32px,5.5vw,56px); }

/* ---- Scroll reveal ------------------------------------------------------ */
.reveal{ opacity: 0; transform: translateY(24px); transition: opacity .7s ease, transform .7s ease; }
.reveal.in{ opacity: 1; transform: none; }

/* ---- Pills / notes ------------------------------------------------------ */
.pill{ display: inline-block; font-family: var(--font-mono); font-size: 12px; letter-spacing: .1em; padding: 6px 13px; border-radius: 999px; border: 1px solid var(--line); color: var(--glow); background: var(--glow-haze); }
.note{ border-left: 3px solid var(--glow); background: rgba(77,155,255,.05); padding: 16px 20px; border-radius: 0 10px 10px 0; font-size: 15px; }
.note b{ color: var(--foam); }

/* ---- Host institution logo (Nitte / NMAMIT) ----------------------------- */
/* Reversed (white) logo sits directly on the deep background and is lit with
   a soft bioluminescent glow, so it reads clearly and belongs to the theme. */
.foot-logo{
  display: flex; flex-direction: column; align-items: center; gap: 16px;
  padding-bottom: 40px; margin-bottom: 36px; border-bottom: 1px solid var(--line);
}
.host-logo-label{
  font-family: var(--font-mono); font-size: 11px; letter-spacing: .3em;
  text-transform: uppercase; color: var(--mist-dim);
  display: inline-flex; align-items: center; gap: 12px;
}
.host-logo-label::before, .host-logo-label::after{
  content: ""; width: 26px; height: 1px; background: var(--line);
}
.host-logo{ position: relative; display: inline-block; line-height: 0; padding: 6px 12px; }
.host-logo::before{
  content: ""; position: absolute; left: 50%; top: 50%; width: 116%; height: 200%;
  transform: translate(-50%, -50%); z-index: 0; pointer-events: none;
  background: radial-gradient(closest-side, rgba(77,155,255,.20), transparent 72%);
}
.host-logo img{
  position: relative; z-index: 1;
  width: clamp(220px, 42vw, 380px); height: auto; display: block;
  filter: drop-shadow(0 0 20px rgba(77,155,255,.32));
}

/* ==========================================================================
   RESPONSIVE
   ========================================================================== */
@media (max-width: 900px){
  .grid-4{ grid-template-columns: repeat(2,1fr); }
  .grid-3{ grid-template-columns: repeat(2,1fr); }
  .facts{ grid-template-columns: repeat(2,1fr); }
  .cols-2, .grid-2{ grid-template-columns: 1fr; }
  .speaker{ grid-template-columns: 1fr; }
  .speaker .avatar{ margin: 0 auto; }
  .footer .grid-foot{ grid-template-columns: 1fr 1fr; }

  .nav-toggle{ display: block; }
  .nav-links{
    position: fixed; inset: var(--nav-h) 0 auto 0; flex-direction: column; align-items: stretch; gap: 2px;
    background: var(--abyss); padding: 14px var(--gutter) 24px; box-shadow: 0 24px 50px -20px rgba(0,0,0,.9);
    border-bottom: 1px solid var(--line); transform: translateY(-130%); transition: transform .3s ease; max-height: 85vh; overflow-y: auto;
  }
  .nav-links.open{ transform: none; }
  .nav-links a{ padding: 13px 6px; font-size: 16px; border-bottom: 1px solid var(--line); border-radius: 0; }
  .nav-links .cta-link{ margin: 10px 0 0; text-align: center; border-radius: 10px; border-bottom: 0; }
}
@media (max-width: 768px){
  .auv{ width: clamp(120px, 34vw, 180px); opacity: .5; }
  .auv-track{ right: -2%; }
}
@media (max-width: 560px){
  .grid-4, .grid-3, .facts{ grid-template-columns: 1fr; }
  .hero .facts{ grid-template-columns: 1fr 1fr; }
  .footer .grid-foot{ grid-template-columns: 1fr; }
  body{ font-size: 16px; }
  .cd-cell{ min-width: 62px; padding: 10px 12px; }

  /* Tighten the hero so the full highlights strip is visible without scrolling */
  .hero .wrap{ padding-top: 22px; padding-bottom: 30px; }
  .hero-tag{ margin-bottom: 12px; font-size: 12px; }
  .hero h1{ font-size: clamp(25px, 7.4vw, 38px); }
  .hero h1 .sub{ font-size: 15px; margin-top: 9px; line-height: 1.35; }
  .hero-meta{ margin: 13px 0 15px; gap: 6px 16px; font-size: 12.5px; }
  .hero-actions{ gap: 9px; }
  .hero-actions .btn{ padding: 11px 17px; font-size: 14px; }
  .hero .facts{ margin-top: 16px; }
  .hero .facts div{ padding: 11px 13px; }
  .hero .facts b{ font-size: 23px; }
  .hero .facts span{ font-size: 10.5px; }
}

/* ---- Reduced motion ----------------------------------------------------- */
@media (prefers-reduced-motion: reduce){
  *{ animation: none !important; transition: none !important; scroll-behavior: auto !important; }
  .reveal{ opacity: 1; transform: none; }
}