/* ============================================================
   Do Robots Need World Models? — CoRL 2026 Workshop
   Light, minimal academic aesthetic. Edit theme vars below.
   ============================================================ */
:root {
  --bg:        #ffffff;
  --bg-alt:    #f6f8f7;
  --ink:       #1a1d1b;
  --ink-soft:  #4a524e;
  --ink-faint: #8a938e;
  --line:      #e4e8e6;
  --accent:    #1f8a5b;   /* emerald — primary accent */
  --accent-dk: #166a46;
  --explicit:  #2563eb;   /* "for / explicit" side  */
  --implicit:  #db5d2a;   /* "against / implicit" side */
  --hybrid:    #7c3aed;   /* "structured / hybrid" side */
  --tbd:       #b07a13;
  --maxw:      1080px;
  --radius:    14px;
  --shadow:    0 1px 2px rgba(0,0,0,.04), 0 8px 24px rgba(0,0,0,.05);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 76px; }
body {
  margin: 0;
  font-family: "Inter", system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent-dk); text-decoration: none; }
a:hover { text-decoration: underline; }
.accent { color: var(--accent); }
.tbd { color: var(--tbd); font-style: italic; }

/* ---------- NAV ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; justify-content: space-between;
  gap: 1rem;
  padding: .7rem clamp(1rem, 4vw, 2rem);
  background: rgba(255,255,255,.85);
  backdrop-filter: saturate(140%) blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav__brand { font-weight: 700; color: var(--ink); font-size: .98rem; letter-spacing: -.01em; }
.nav__links { display: flex; gap: 1.2rem; flex-wrap: wrap; }
.nav__links a { color: var(--ink-soft); font-size: .9rem; font-weight: 500; }
.nav__links a:hover { color: var(--accent-dk); text-decoration: none; }
.nav__toggle { display: none; background: none; border: 0; font-size: 1.4rem; cursor: pointer; color: var(--ink); }

/* ---------- HERO ---------- */
.hero {
  background: radial-gradient(120% 120% at 50% 0%, #f0f7f3 0%, #ffffff 60%);
  border-bottom: 1px solid var(--line);
  padding: clamp(3.5rem, 9vw, 6.5rem) clamp(1rem, 4vw, 2rem);
}
.hero__inner { max-width: var(--maxw); margin: 0 auto; text-align: center; }
.badge {
  display: inline-block; font-weight: 600; font-size: .8rem; letter-spacing: .04em;
  text-transform: uppercase; color: var(--accent-dk);
  background: #e7f3ec; border: 1px solid #c7e6d4;
  padding: .35rem .8rem; border-radius: 999px;
}
.hero__title {
  font-family: "Newsreader", Georgia, serif;
  font-weight: 600; letter-spacing: -.02em;
  font-size: clamp(2.4rem, 7vw, 4.4rem); line-height: 1.05;
  margin: 1.1rem 0 .6rem;
}
.hero__subtitle { font-size: clamp(1.05rem, 2.4vw, 1.4rem); color: var(--ink-soft); max-width: 760px; margin: 0 auto .9rem; }
.hero__meta { color: var(--ink-faint); font-weight: 500; margin: 0 0 1.8rem; }
.hero__cta { display: flex; gap: .7rem; justify-content: center; flex-wrap: wrap; }

/* ---------- BUTTONS ---------- */
.btn {
  display: inline-block; padding: .62rem 1.15rem; border-radius: 999px;
  border: 1px solid var(--line); background: #fff; color: var(--ink);
  font-weight: 600; font-size: .92rem; transition: transform .08s ease, box-shadow .15s ease, background .15s ease;
}
.btn:hover { text-decoration: none; box-shadow: var(--shadow); transform: translateY(-1px); }
.btn--primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn--primary:hover { background: var(--accent-dk); }
.btn[data-tbd] { opacity: .65; cursor: not-allowed; }

/* ---------- SECTIONS ---------- */
.section { max-width: var(--maxw); margin: 0 auto; padding: clamp(3rem, 7vw, 5rem) clamp(1rem, 4vw, 2rem); }
.section--alt { max-width: none; background: var(--bg-alt); border-block: 1px solid var(--line); }
.section--alt > * { max-width: var(--maxw); margin-inline: auto; }
.section__title {
  font-family: "Newsreader", Georgia, serif; font-weight: 600;
  font-size: clamp(1.8rem, 4vw, 2.5rem); letter-spacing: -.02em; margin: 0 0 .4rem;
}
.section__title::after { content: ""; display: block; width: 48px; height: 3px; background: var(--accent); border-radius: 3px; margin-top: .7rem; }
.section__lead { color: var(--ink-soft); max-width: 820px; font-size: 1.02rem; margin: 1.1rem 0 2rem; }
.prose p { color: var(--ink-soft); max-width: 820px; margin: 0 0 1.1rem; }
.prose strong { color: var(--ink); }

/* ---------- MOTIONS ---------- */
.motions { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 1.1rem; }
.motion {
  position: relative; background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1.6rem 1.4rem 1.3rem; box-shadow: var(--shadow);
}
.motion__num {
  font-family: "Newsreader", serif; font-size: 1.5rem; font-weight: 600;
  color: var(--accent); background: #e7f3ec; border-radius: 10px;
  width: 2.4rem; height: 2.4rem; display: grid; place-items: center; margin-bottom: .8rem;
}
.motion h3 { font-size: 1.06rem; line-height: 1.35; margin: 0 0 .6rem; letter-spacing: -.01em; }
.motion p { color: var(--ink-soft); font-size: .94rem; margin: 0 0 .7rem; }
.motion__open { color: var(--ink); font-size: .9rem; border-top: 1px dashed var(--line); padding-top: .7rem; margin-bottom: 0; }
.motion__open strong { color: var(--accent-dk); }

/* ---------- SPEAKERS ---------- */
.speakers { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 1.1rem; }
.speaker { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 1.5rem 1.4rem; box-shadow: var(--shadow); }
.speaker__head { display: flex; align-items: center; gap: .6rem; flex-wrap: wrap; }
.speaker__head h3 { margin: 0; font-size: 1.2rem; letter-spacing: -.01em; }
.speaker__affil { color: var(--ink-faint); font-size: .92rem; margin: .15rem 0 .8rem; }
.speaker__blurb { color: var(--ink-soft); font-size: .93rem; margin: .8rem 0 0; }

.pill { font-size: .7rem; font-weight: 700; text-transform: uppercase; letter-spacing: .04em; padding: .18rem .5rem; border-radius: 999px; }
.pill--committed { color: var(--accent-dk); background: #e7f3ec; }
.pill--online { color: #475569; background: #eef2f6; }

.side { display: inline-block; font-size: .78rem; font-weight: 600; padding: .25rem .6rem; border-radius: 8px; border: 1px solid currentColor; }
.side--explicit { color: var(--explicit); background: #eff4ff; }
.side--implicit { color: var(--implicit); background: #fdf1ea; }
.side--hybrid   { color: var(--hybrid);   background: #f5f0ff; }
.side-tag { display: inline-block; font-size: .72rem; font-weight: 600; padding: .1rem .45rem; border-radius: 6px; margin-left: .3rem; white-space: nowrap; }
.side-tag.side--explicit { color: var(--explicit); background: #eff4ff; border: 1px solid #cdddff; }
.side-tag.side--implicit { color: var(--implicit); background: #fdf1ea; border: 1px solid #f6d6c4; }
.side-tag.side--hybrid   { color: var(--hybrid);   background: #f5f0ff; border: 1px solid #e0d4fb; }

/* ---------- TABLES ---------- */
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); background: #fff; }
table { width: 100%; border-collapse: collapse; font-size: .94rem; }
.schedule th, .schedule td, .dates td { padding: .8rem 1rem; text-align: left; border-bottom: 1px solid var(--line); }
.schedule thead th { background: #fafbfb; font-weight: 600; color: var(--ink-soft); font-size: .82rem; text-transform: uppercase; letter-spacing: .03em; }
.schedule tbody tr:last-child td, .dates tr:last-child td { border-bottom: 0; }
.schedule td:first-child, .dates td:first-child { font-variant-numeric: tabular-nums; white-space: nowrap; color: var(--ink); font-weight: 500; }
.schedule td:nth-child(2) { color: var(--ink-faint); white-space: nowrap; }
.dates td:last-child { text-align: right; font-weight: 500; }

/* ---------- CFP ---------- */
.cfp { display: grid; grid-template-columns: 2fr 1fr; gap: 1.6rem; align-items: start; }
.cfp__topics { border-top: 1px solid var(--line); padding-top: 1rem; }
.cfp__facts { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 1.4rem; box-shadow: var(--shadow); position: sticky; top: 90px; }
.cfp__facts h3 { margin: 0 0 .8rem; font-size: 1.05rem; }
.cfp__facts dl { margin: 0; display: grid; grid-template-columns: auto; gap: .7rem; }
.cfp__facts dt { font-size: .74rem; text-transform: uppercase; letter-spacing: .04em; color: var(--ink-faint); font-weight: 700; }
.cfp__facts dd { margin: 0 0 .3rem; font-size: .95rem; color: var(--ink); font-weight: 500; }

/* ---------- PEOPLE (organizers) ---------- */
.people { display: grid; grid-template-columns: repeat(auto-fit, minmax(170px, 1fr)); gap: 1.6rem; }
.person { margin: 0; text-align: center; }
.person img {
  width: 130px; height: 130px; border-radius: 50%; object-fit: cover;
  border: 3px solid #fff; box-shadow: var(--shadow); margin-bottom: .8rem;
  background: var(--bg-alt);
}
.person__name { display: block; font-weight: 600; letter-spacing: -.01em; }
.person__affil { display: block; color: var(--ink-faint); font-size: .88rem; margin: .1rem 0 .25rem; }
.person__link { font-size: .82rem; word-break: break-word; }

/* ---------- FOOTER ---------- */
.footer { background: var(--ink); color: #cdd4d0; padding: clamp(2.5rem, 6vw, 4rem) clamp(1rem, 4vw, 2rem); margin-top: 2rem; }
.footer__inner { max-width: var(--maxw); margin: 0 auto; text-align: center; }
.footer__title { font-family: "Newsreader", serif; font-size: 1.5rem; color: #fff; margin: 0 0 .5rem; }
.footer p { margin: .3rem 0; font-size: .94rem; }
.footer a { color: #7fe0b0; }
.footer__note { color: var(--ink-faint); font-size: .85rem; margin-top: 1rem; }

/* ---------- RESPONSIVE ---------- */
@media (max-width: 820px) {
  .cfp { grid-template-columns: 1fr; }
  .cfp__facts { position: static; }
}
@media (max-width: 720px) {
  .nav__links {
    display: none; position: absolute; top: 100%; left: 0; right: 0;
    flex-direction: column; gap: 0; background: #fff; border-bottom: 1px solid var(--line); padding: .5rem 0;
  }
  .nav__links.open { display: flex; }
  .nav__links a { padding: .7rem clamp(1rem, 4vw, 2rem); }
  .nav__toggle { display: block; }
}