/* ===========================================================
   AIASci 2026 — AI-Assisted Science Workshop @ AIAS 2026
   A self-contained modern theme (no framework dependency).
   =========================================================== */

:root {
  --ink:        #0c1226;   /* deep navy ink            */
  --ink-soft:   #1b2444;
  --paper:      #ffffff;
  --paper-2:    #f5f7fc;   /* alternating section bg   */
  --paper-3:    #eef2fb;
  --line:       #dfe4f1;
  --text:       #283250;
  --text-soft:  #5b6481;
  --muted:      #6b7693;
  --brand:      #5b6cff;   /* electric indigo          */
  --brand-2:    #18c8d8;   /* cyan accent              */
  --brand-3:    #8a5bff;   /* violet accent            */
  --accent-warm:#ff7a59;
  --radius:     18px;
  --radius-sm:  12px;
  --shadow:     0 18px 40px -22px rgba(16, 24, 64, .45);
  --shadow-sm:  0 8px 22px -14px rgba(16, 24, 64, .4);
  --maxw:       1080px;
  --font:       "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-head:  "Space Grotesk", "Inter", system-ui, sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 78px; }

body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: var(--paper);
  line-height: 1.7;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--brand); text-decoration: none; transition: color .18s ease; }
a:hover { color: var(--brand-3); }

h1, h2, h3, h4 { font-family: var(--font-head); color: var(--ink); line-height: 1.2; }

/* ---------- Layout helpers ---------- */
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 22px; }

section { padding: 84px 0; }
section.alt { background: var(--paper-2); }

.section-head { text-align: center; max-width: 760px; margin: 0 auto 48px; }
.section-head .eyebrow {
  display: inline-block;
  font-family: var(--font-head);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--brand);
  margin-bottom: 12px;
}
.section-head h2 {
  font-size: clamp(28px, 4vw, 40px);
  margin: 0 0 14px;
  letter-spacing: -.01em;
}
.section-head p { color: var(--muted); font-size: 18px; margin: 0; }

/* ---------- Nav ---------- */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(255,255,255,.82);
  backdrop-filter: saturate(160%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  max-width: 1180px; margin: 0 auto; padding: 0 22px;
  height: 64px; display: flex; align-items: center; justify-content: space-between;
}
.brand { display: flex; align-items: center; gap: 10px; font-family: var(--font-head); font-weight: 700; color: var(--ink); font-size: 19px; }
.brand .dot {
  width: 26px; height: 26px; border-radius: 8px;
  background: linear-gradient(135deg, var(--brand-2), var(--brand) 55%, var(--brand-3));
  box-shadow: 0 4px 14px -4px var(--brand);
}
.brand small { font-family: var(--font); font-weight: 500; color: var(--muted); font-size: 12px; letter-spacing: .04em; }
.nav-links { display: flex; gap: 4px; align-items: center; }
.nav-links a {
  font-size: 14.5px; font-weight: 500; color: var(--text);
  padding: 8px 13px; border-radius: 9px;
}
.nav-links a:hover { background: var(--paper-3); color: var(--ink); }
.nav-toggle { display: none; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--ink); margin: 5px 0; border-radius: 2px; transition: .25s; }

@media (max-width: 880px) {
  .nav-links {
    position: absolute; top: 64px; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: var(--paper); border-bottom: 1px solid var(--line);
    padding: 8px; max-height: 0; overflow: hidden; transition: max-height .3s ease; box-shadow: var(--shadow-sm);
  }
  .nav-links.open { max-height: 460px; }
  .nav-links a { padding: 12px 14px; border-radius: 8px; }
  .nav-toggle { display: block; }
}

/* ---------- Hero ---------- */
.hero {
  position: relative; overflow: hidden;
  background:
    radial-gradient(900px 500px at 12% -10%, rgba(91,108,255,.42), transparent 60%),
    radial-gradient(800px 520px at 95% 10%, rgba(24,200,216,.30), transparent 55%),
    radial-gradient(700px 600px at 60% 120%, rgba(138,91,255,.34), transparent 60%),
    var(--ink);
  color: #eaf0ff; padding: 150px 0 110px; text-align: center;
}
.hero::after {
  content:""; position:absolute; inset:0;
  background-image:
    linear-gradient(rgba(255,255,255,.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.05) 1px, transparent 1px);
  background-size: 46px 46px;
  mask-image: radial-gradient(70% 70% at 50% 35%, #000 30%, transparent 75%);
  pointer-events: none;
}
.hero .wrap { position: relative; z-index: 2; }
.hero .pill {
  display: inline-flex; align-items: center; gap: 9px;
  background: rgba(255,255,255,.1); border: 1px solid rgba(255,255,255,.2);
  color: #d9e2ff; padding: 7px 16px; border-radius: 999px;
  font-size: 13.5px; font-weight: 500; letter-spacing: .04em; margin-bottom: 26px;
}
.hero .pill b { color: #fff; font-weight: 700; }
.hero .acronym {
  font-family: var(--font-head); font-weight: 700;
  font-size: clamp(46px, 9vw, 92px); letter-spacing: -.02em; line-height: 1; margin: 0;
  background: linear-gradient(120deg, #ffffff 20%, #b9c6ff 55%, #7ff0fb);
  -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent;
}
.hero .full-title {
  font-family: var(--font-head); font-weight: 500;
  font-size: clamp(18px, 2.6vw, 25px); color: #cdd8ff; max-width: 820px;
  margin: 18px auto 0; line-height: 1.4;
}
.hero .venue {
  margin: 30px auto 0; max-width: 720px; color: #b7c3ee; font-size: 17px;
}
.hero .venue a { color: #8ff3ff; }
.hero-meta { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; margin-top: 34px; }
.hero-meta .chip {
  display: inline-flex; align-items: center; gap: 8px;
  background: rgba(255,255,255,.08); border: 1px solid rgba(255,255,255,.16);
  border-radius: 12px; padding: 10px 16px; font-size: 14.5px; color: #e7edff;
}
.hero-meta .chip svg { width: 17px; height: 17px; opacity: .9; }
.hero-cta { margin-top: 38px; display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center; gap: 9px;
  font-family: var(--font-head); font-weight: 600; font-size: 15px;
  padding: 13px 24px; border-radius: 12px; cursor: pointer; border: 1px solid transparent;
  transition: transform .15s ease, box-shadow .2s ease, background .2s ease;
}
.btn-primary { background: linear-gradient(135deg, var(--brand-2), var(--brand) 60%, var(--brand-3)); color: #fff; box-shadow: 0 14px 30px -12px var(--brand); }
.btn-primary:hover { transform: translateY(-2px); color: #fff; box-shadow: 0 20px 38px -12px var(--brand); }
.btn-ghost { background: rgba(255,255,255,.06); border-color: rgba(255,255,255,.28); color: #eaf0ff; }
.btn-ghost:hover { background: rgba(255,255,255,.14); color: #fff; transform: translateY(-2px); }

/* ---------- Pillars ---------- */
.pillars { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.pillar {
  background: var(--paper); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 28px 26px; box-shadow: var(--shadow-sm); position: relative; overflow: hidden;
  transition: transform .2s ease, box-shadow .2s ease;
}
.pillar:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.pillar::before { content:""; position:absolute; top:0; left:0; right:0; height:4px; }
.pillar.p1::before { background: linear-gradient(90deg, var(--brand-2), var(--brand)); }
.pillar.p2::before { background: linear-gradient(90deg, var(--brand), var(--brand-3)); }
.pillar.p3::before { background: linear-gradient(90deg, var(--brand-3), var(--accent-warm)); }
.pillar .tag { font-family: var(--font-head); font-size: 13px; font-weight: 600; letter-spacing: .12em; text-transform: uppercase; color: var(--brand); }
.pillar h3 { font-size: 21px; margin: 8px 0 10px; }
.pillar p { margin: 0; color: var(--muted); font-size: 15.5px; }

/* ---------- Prose blocks ---------- */
.prose { max-width: 820px; margin: 0 auto; }
.prose p { margin: 0 0 18px; text-align: justify; }
.lead { font-size: 19px; color: var(--text); }

/* ---------- Topic lists ---------- */
.topics { display: grid; grid-template-columns: 1fr; gap: 18px; max-width: 900px; margin: 0 auto; }
.topic-card {
  background: var(--paper); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 24px 26px; box-shadow: var(--shadow-sm);
}
.topic-card h3 { display: flex; align-items: baseline; gap: 12px; font-size: 20px; margin: 0 0 14px; }
.topic-card h3 .badge {
  font-family: var(--font-head); font-size: 13px; font-weight: 700; color: #fff;
  background: linear-gradient(135deg, var(--brand), var(--brand-3));
  padding: 4px 11px; border-radius: 8px; letter-spacing: .04em; flex: none;
}
.topic-card ul { margin: 0; padding-left: 0; list-style: none; columns: 2; column-gap: 32px; }
.topic-card li { position: relative; padding: 5px 0 5px 22px; font-size: 15.5px; color: var(--text); break-inside: avoid; }
.topic-card li::before { content:""; position: absolute; left: 4px; top: 13px; width: 7px; height: 7px; border-radius: 2px; background: var(--brand-2); }
@media (max-width: 640px){ .topic-card ul { columns: 1; } }

/* CFP sub-headings & leads */
.cfp-subhead {
  max-width: 900px; margin: 0 auto 10px; font-size: 26px; text-align: center;
  display: flex; align-items: center; justify-content: center; gap: 14px;
}
.cfp-subhead::before, .cfp-subhead::after {
  content: ""; height: 2px; width: 46px; border-radius: 2px;
  background: linear-gradient(90deg, var(--brand-2), var(--brand-3));
}
.cfp-lead { max-width: 820px; margin: 0 auto 30px; text-align: center; color: var(--muted); font-size: 17px; }
.subs-lead { max-width: 820px; margin: 28px auto 0; text-align: center; font-family: var(--font-head); font-weight: 600; color: var(--ink); font-size: 17px; }

/* callout / info box */
.callout {
  max-width: 900px; margin: 28px auto 0;
  background: linear-gradient(135deg, rgba(91,108,255,.07), rgba(24,200,216,.07));
  border: 1px solid var(--line); border-left: 4px solid var(--brand);
  border-radius: var(--radius-sm); padding: 20px 24px;
}
.callout p { margin: 0 0 10px; }
.callout p:last-child { margin: 0; }

/* submission links */
.subs { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px,1fr)); gap: 16px; max-width: 900px; margin: 26px auto 0; }
.sub-link {
  display: block; background: var(--paper); border: 1px solid var(--line); border-radius: var(--radius-sm);
  padding: 18px 20px; box-shadow: var(--shadow-sm); transition: transform .18s ease, border-color .18s ease;
}
.sub-link:hover { transform: translateY(-3px); border-color: var(--brand); }
.sub-link b { display: block; font-family: var(--font-head); color: var(--ink); font-size: 16px; margin-bottom: 4px; }
.sub-link span { color: var(--muted); font-size: 14px; }

/* ---------- Dates table ---------- */
.dates { max-width: 820px; margin: 0 auto; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow-sm); background: var(--paper); }
.date-row { display: grid; grid-template-columns: 1fr auto; gap: 16px; padding: 18px 26px; border-bottom: 1px solid var(--line); align-items: center; }
.date-row:last-child { border-bottom: 0; }
.date-row:nth-child(odd) { background: var(--paper-2); }
.date-row .ev { font-weight: 500; color: var(--text); }
.date-row .dt { font-family: var(--font-head); font-weight: 600; color: var(--ink); white-space: nowrap; }
.date-row.highlight { background: linear-gradient(135deg, rgba(91,108,255,.1), rgba(138,91,255,.08)); }
.date-row.highlight .dt { color: var(--brand); }
.tba { display:inline-block; font-size: 12px; font-weight:600; color:var(--brand); background: rgba(91,108,255,.12); padding: 2px 9px; border-radius: 6px; }
.dates-note { text-align:center; color: var(--muted); font-size: 14.5px; margin-top: 16px; }

/* ---------- People grids ---------- */
.people { display: grid; grid-template-columns: repeat(5, 1fr); gap: 26px; max-width: 980px; margin: 0 auto; }
@media (max-width: 920px){ .people { grid-template-columns: repeat(3, 1fr); } }
@media (max-width: 560px){ .people { grid-template-columns: repeat(2, 1fr); } }
.person { text-align: center; display: block; color: inherit; text-decoration: none; border-radius: var(--radius); padding: 14px 8px; transition: transform .2s ease, background .2s ease, box-shadow .2s ease; }
.person .ph {
  width: 130px; height: 130px; margin: 0 auto 14px; border-radius: 50%; overflow: hidden;
  border: 3px solid var(--paper); box-shadow: 0 0 0 2px var(--line), var(--shadow-sm);
  background: var(--paper-3); transition: box-shadow .2s ease;
}
.person .ph img { width: 100%; height: 100%; object-fit: cover; display: block; transition: transform .3s ease; }
.person h3 { font-size: 18px; margin: 0 0 4px; transition: color .18s ease; }
.person .role { color: var(--muted); font-size: 14px; line-height: 1.4; }
.person .aff { color: var(--text); font-size: 14px; }
/* clickable organizer cards */
a.person { cursor: pointer; }
a.person:hover { color: inherit; transform: translateY(-6px); background: var(--paper); box-shadow: var(--shadow); }
a.person:hover .ph { box-shadow: 0 0 0 3px var(--brand), var(--shadow); }
a.person:hover .ph img { transform: scale(1.08); }
a.person:hover h3 { color: var(--brand); }

/* speakers */
.speakers { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; max-width: 980px; margin: 0 auto; }
@media (max-width: 820px){ .speakers { grid-template-columns: repeat(2, 1fr); } }
.speaker {
  background: var(--paper); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 24px 20px; text-align: center; box-shadow: var(--shadow-sm);
  transition: transform .18s ease;
}
.speaker:hover { transform: translateY(-4px); }
.speaker .av {
  width: 64px; height: 64px; margin: 0 auto 14px; border-radius: 16px;
  display: grid; place-items: center; font-family: var(--font-head); font-weight: 700; font-size: 22px; color: #fff;
  background: linear-gradient(135deg, var(--brand-2), var(--brand) 60%, var(--brand-3));
}
.speaker h3 { font-size: 17px; margin: 0 0 4px; }
.speaker p { margin: 0; color: var(--muted); font-size: 14px; }
.tentative-note { text-align:center; color: var(--muted); font-size: 14px; margin-top: 22px; font-style: italic; }

/* ---------- Committee ---------- */
.committee { columns: 3; column-gap: 30px; max-width: 940px; margin: 0 auto; }
@media (max-width: 760px){ .committee { columns: 2; } }
@media (max-width: 480px){ .committee { columns: 1; } }
.committee .pc { break-inside: avoid; padding: 6px 0 6px 20px; position: relative; font-size: 15px; }
.committee .pc::before { content:""; position:absolute; left:0; top:13px; width: 7px; height: 7px; border-radius: 50%; background: var(--brand-2); }
.committee .pc b { color: var(--ink); font-weight: 600; }
.committee .pc span { color: var(--muted); font-size: 13.5px; display: block; }

/* ---------- Previous / related workshops ---------- */
.work-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; max-width: 940px; margin: 0 auto; }
@media (max-width: 760px){ .work-grid { grid-template-columns: 1fr; } }
.work-col h3 { font-size: 19px; margin: 0 0 16px; display: flex; align-items: center; gap: 10px; }
.work-item {
  background: var(--paper); border: 1px solid var(--line); border-radius: var(--radius-sm);
  padding: 16px 18px; margin-bottom: 12px; box-shadow: var(--shadow-sm);
}
.work-item a { font-family: var(--font-head); font-weight: 600; }
.work-item .meta { color: var(--muted); font-size: 14px; margin-top: 4px; }

/* ---------- Contact ---------- */
.contact-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; max-width: 820px; margin: 0 auto; }
@media (max-width: 680px){ .contact-grid { grid-template-columns: 1fr; } }
.contact-card {
  text-align: center; background: var(--paper); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 28px 22px; box-shadow: var(--shadow-sm);
}
.contact-card .ic {
  width: 52px; height: 52px; margin: 0 auto 14px; border-radius: 14px; display: grid; place-items: center;
  background: linear-gradient(135deg, rgba(91,108,255,.14), rgba(24,200,216,.14)); color: var(--brand);
}
.contact-card .ic svg { width: 24px; height: 24px; }
.contact-card h4 { margin: 0 0 6px; font-size: 16px; }
.contact-card a { font-size: 15px; word-break: break-word; }

/* ---------- Footer ---------- */
footer { background: var(--ink); color: #aab6e0; padding: 44px 0; text-align: center; font-size: 14.5px; }
footer .brand { justify-content: center; color: #fff; margin-bottom: 12px; }
footer a { color: #9fc7ff; }
footer .fine { margin-top: 10px; color: #6c79a8; font-size: 13px; }

/* reveal-on-scroll */
.reveal { opacity: 0; transform: translateY(18px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }