/* ===================== AutoResearch 2026 ===================== */
:root {
  --indigo: #4f46e5;
  --indigo-600: #4338ca;
  --violet: #7c3aed;
  --cyan: #06b6d4;
  --ink: #0f172a;
  --ink-2: #1e293b;
  --slate: #475569;
  --slate-2: #64748b;
  --line: #e2e8f0;
  --bg: #ffffff;
  --bg-alt: #f6f7fb;
  --card: #ffffff;
  --radius: 16px;
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, .06), 0 1px 3px rgba(15, 23, 42, .08);
  --shadow-md: 0 10px 30px rgba(15, 23, 42, .08);
  --shadow-lg: 0 24px 60px rgba(79, 70, 229, .18);
  --maxw: 1080px;
  --nav-h: 66px;
  --grad: linear-gradient(120deg, #4f46e5 0%, #7c3aed 45%, #06b6d4 100%);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: var(--nav-h); }
body {
  margin: 0;
  font-family: "Inter", system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  color: var(--ink-2);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--indigo); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3, h4 { font-family: "Space Grotesk", "Inter", sans-serif; color: var(--ink); line-height: 1.2; }
.container { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ===================== NAVBAR ===================== */
.nav {
  position: sticky; top: 0; z-index: 50;
  height: var(--nav-h);
  background: rgba(255, 255, 255, .82);
  backdrop-filter: saturate(160%) blur(12px);
  -webkit-backdrop-filter: saturate(160%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav-inner { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; height: 100%; display: flex; align-items: center; justify-content: space-between; }
.brand { display: flex; align-items: center; gap: 10px; font-family: "Space Grotesk", sans-serif; font-weight: 700; color: var(--ink); font-size: 1.1rem; }
.brand:hover { text-decoration: none; }
.brand-mark {
  display: inline-grid; place-items: center;
  width: 34px; height: 34px; border-radius: 9px;
  background: var(--grad); color: #fff; font-weight: 800; font-size: .85rem; letter-spacing: .5px;
  box-shadow: var(--shadow-sm);
}
.brand-year { color: var(--indigo); }
.nav-links { display: flex; gap: 22px; }
.nav-links a { color: var(--slate); font-weight: 500; font-size: .92rem; padding: 6px 2px; position: relative; }
.nav-links a:hover { color: var(--ink); text-decoration: none; }
.nav-links a.active { color: var(--indigo); }
.nav-links a.active::after { content: ""; position: absolute; left: 0; right: 0; bottom: -2px; height: 2px; background: var(--grad); border-radius: 2px; }
.nav-toggle { display: none; background: none; border: 0; cursor: pointer; width: 40px; height: 40px; padding: 8px; }
.nav-toggle span { display: block; height: 2px; background: var(--ink); margin: 5px 0; border-radius: 2px; transition: .25s; }

/* ===================== HERO ===================== */
.hero { position: relative; padding: 96px 24px 88px; text-align: center; overflow: hidden; color: #fff; }
.hero-bg { position: absolute; inset: 0; background: var(--grad); }
.hero-bg::after {
  content: ""; position: absolute; inset: 0;
  background:
    radial-gradient(700px 320px at 15% 10%, rgba(255,255,255,.22), transparent 60%),
    radial-gradient(600px 300px at 90% 90%, rgba(6,182,212,.30), transparent 55%);
}
.hero-content { position: relative; max-width: 880px; margin: 0 auto; }
.eyebrow { text-transform: uppercase; letter-spacing: 2.5px; font-size: .78rem; font-weight: 700; opacity: .92; margin: 0 0 14px; }
.hero-title { font-size: clamp(2.6rem, 6vw, 4.4rem); margin: 0; color: #fff; letter-spacing: -1px; }
.hero-sub { font-size: clamp(1.05rem, 2.4vw, 1.5rem); font-weight: 600; margin: 14px 0 0; color: #fff; }
.hero-tagline { max-width: 640px; margin: 18px auto 0; opacity: .95; font-size: 1.02rem; }
.hero-meta { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; margin: 26px 0 0; }
.chip { background: rgba(255, 255, 255, .16); border: 1px solid rgba(255, 255, 255, .28); padding: 7px 14px; border-radius: 999px; font-size: .86rem; font-weight: 500; backdrop-filter: blur(4px); }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; margin-top: 30px; }
.btn { display: inline-block; padding: 12px 22px; border-radius: 11px; font-weight: 600; font-size: .95rem; transition: transform .15s, box-shadow .2s, background .2s; }
.btn:hover { text-decoration: none; transform: translateY(-2px); }
.btn-primary { background: #fff; color: var(--indigo-600); box-shadow: var(--shadow-md); }
.btn-primary:hover { box-shadow: var(--shadow-lg); }
.btn-ghost { background: rgba(255, 255, 255, .12); color: #fff; border: 1px solid rgba(255, 255, 255, .35); }
.btn-ghost:hover { background: rgba(255, 255, 255, .22); }

/* ===================== SECTIONS ===================== */
.section { padding: 78px 0; border-top: 1px solid var(--line); }
.section-alt { background: var(--bg-alt); }
.kicker { text-transform: uppercase; letter-spacing: 2px; font-size: .76rem; font-weight: 800; color: var(--indigo); margin: 0 0 8px; }
.section-title { font-size: clamp(1.7rem, 3.4vw, 2.4rem); margin: 0 0 18px; letter-spacing: -.5px; }
.section-title.sub-block { margin-top: 56px; }
.lead { font-size: 1.12rem; color: var(--slate); max-width: 760px; margin: 0 0 18px; }
.muted { color: var(--slate-2); font-size: .92rem; }
.bullets { padding-left: 20px; }
.bullets li { margin: 7px 0; }

/* ===================== FEATURE CARDS ===================== */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin: 34px 0 8px; }
.feature-card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 26px 22px; box-shadow: var(--shadow-sm); transition: transform .2s, box-shadow .2s; }
.feature-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.feature-icon { font-size: 1.9rem; margin-bottom: 8px; }
.feature-card h3 { margin: 4px 0 8px; font-size: 1.15rem; }
.feature-card p { margin: 0; color: var(--slate); font-size: .96rem; }

.whynow { margin-top: 40px; background: var(--card); border: 1px solid var(--line); border-left: 4px solid var(--indigo); border-radius: 14px; padding: 24px 26px; box-shadow: var(--shadow-sm); }
.whynow-title { margin: 0 0 6px; font-size: 1.2rem; }

/* ===================== TOPICS ===================== */
.topic-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; margin-top: 26px; }
.topic { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 16px 18px; font-size: .96rem; font-weight: 500; color: var(--ink-2); box-shadow: var(--shadow-sm); transition: border-color .2s, transform .2s; }
.topic:hover { border-color: var(--indigo); transform: translateY(-2px); }

/* ===================== TRACKS ===================== */
.track-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; margin: 30px 0; }
.track-card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 28px; box-shadow: var(--shadow-sm); }
.track-card-b { border: 1px solid #c7b9fb; background: linear-gradient(180deg, #faf8ff, #fff); }
.track-tag { display: inline-block; font-size: .74rem; font-weight: 800; letter-spacing: 1px; text-transform: uppercase; padding: 5px 12px; border-radius: 999px; margin-bottom: 12px; }
.track-a { background: #e0e7ff; color: var(--indigo-600); }
.track-b { background: var(--grad); color: #fff; }
.track-card h3 { margin: 0 0 12px; font-size: 1.25rem; }

.callout { display: flex; gap: 18px; align-items: flex-start; background: #ecfeff; border: 1px solid #a5f3fc; border-radius: var(--radius); padding: 24px 26px; margin: 8px 0 30px; }
.callout-icon { font-size: 1.8rem; }
.callout h3 { margin: 0 0 6px; }
.callout p { margin: 0; color: var(--ink-2); }

.cfp-extra { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; }
.cfp-extra h4 { margin: 0 0 6px; color: var(--indigo-600); }
.cfp-extra p { margin: 0; color: var(--slate); }

/* ===================== TIMELINE ===================== */
.timeline { list-style: none; padding: 0; margin: 26px 0 0; max-width: 720px; }
.timeline li { display: flex; gap: 20px; padding: 16px 0; border-bottom: 1px dashed var(--line); align-items: baseline; }
.timeline li:last-child { border-bottom: 0; }
.tl-date { flex: 0 0 130px; font-weight: 700; color: var(--indigo-600); font-family: "Space Grotesk", sans-serif; }
.tl-event { color: var(--ink-2); }

/* ===================== SCHEDULE TABLE ===================== */
.table-wrap { overflow-x: auto; margin-top: 24px; border-radius: var(--radius); border: 1px solid var(--line); box-shadow: var(--shadow-sm); }
.schedule { width: 100%; border-collapse: collapse; background: var(--card); }
.schedule th, .schedule td { text-align: left; padding: 14px 18px; border-bottom: 1px solid var(--line); }
.schedule thead th { background: var(--ink); color: #fff; font-family: "Space Grotesk", sans-serif; font-size: .9rem; }
.schedule tbody tr:last-child td { border-bottom: 0; }
.schedule tbody tr:nth-child(even) { background: #fafbff; }
.schedule td:first-child { white-space: nowrap; font-weight: 600; color: var(--indigo-600); width: 150px; }

/* ===================== PEOPLE CARDS ===================== */
.card-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; margin-top: 28px; }
.person { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; text-align: center; box-shadow: var(--shadow-sm); margin: 0; transition: transform .2s, box-shadow .2s; }
.person:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.avatar { width: 96px; height: 96px; border-radius: 50%; object-fit: cover; margin: 0 auto 12px; display: block; border: 3px solid #eef2ff; }
.avatar-tba { display: grid; place-items: center; background: linear-gradient(135deg, #eef2ff, #f5f3ff); color: var(--slate-2); font-weight: 700; font-family: "Space Grotesk", sans-serif; letter-spacing: 1px; }
.person h3 { margin: 0 0 4px; font-size: 1.05rem; }
.person .affil { margin: 0 0 8px; color: var(--slate); font-size: .9rem; }
.person .tag { display: inline-block; background: #e0e7ff; color: var(--indigo-600); font-size: .72rem; font-weight: 700; padding: 3px 10px; border-radius: 999px; margin: 0 0 8px; }
.person .talk { margin: 0; font-size: .86rem; color: var(--slate); }
.person-tba p { margin: 0; color: var(--slate-2); font-size: .92rem; }

/* ===================== SPONSORS ===================== */
.sponsor-row { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 26px; }
.sponsor-slot { display: grid; place-items: center; height: 120px; border: 2px dashed var(--line); border-radius: var(--radius); color: var(--slate-2); font-weight: 500; background: var(--card); }

/* ===================== CONTACT ===================== */
.contact-inner { text-align: center; }
.contact-inner .lead { margin-left: auto; margin-right: auto; }
.contact-email { font-size: 1.3rem; font-weight: 700; font-family: "Space Grotesk", sans-serif; margin: 8px 0 14px; }

/* ===================== FOOTER ===================== */
.footer { background: var(--ink); color: #cbd5e1; padding: 48px 0 24px; }
.footer-inner { display: flex; justify-content: space-between; gap: 30px; flex-wrap: wrap; }
.footer strong { color: #fff; margin-left: 8px; }
.footer .muted { color: #94a3b8; max-width: 420px; margin: 10px 0 0; }
.footer .brand-mark { vertical-align: middle; }
.footer-links { display: flex; flex-direction: column; gap: 10px; }
.footer-links a { color: #cbd5e1; font-size: .94rem; }
.footer-links a:hover { color: #fff; }
.copyright { text-align: center; color: #64748b; font-size: .85rem; margin: 36px 0 0; border-top: 1px solid #1e293b; padding-top: 20px; }

/* ===================== RESPONSIVE ===================== */
@media (max-width: 920px) {
  .feature-grid, .topic-grid, .sponsor-row { grid-template-columns: repeat(2, 1fr); }
  .card-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 760px) {
  .nav-links {
    position: fixed; top: var(--nav-h); left: 0; right: 0;
    background: #fff; border-bottom: 1px solid var(--line);
    flex-direction: column; gap: 0; padding: 8px 0;
    transform: translateY(-130%); transition: transform .28s ease; box-shadow: var(--shadow-md);
  }
  .nav-links.open { transform: translateY(0); }
  .nav-links a { padding: 13px 24px; }
  .nav-toggle { display: block; }
  .track-grid, .cfp-extra { grid-template-columns: 1fr; }
  .feature-grid, .topic-grid, .card-grid, .sponsor-row { grid-template-columns: 1fr; }
  .footer-inner { flex-direction: column; }
  .timeline li { flex-direction: column; gap: 2px; }
  .tl-date { flex-basis: auto; }
}