/* ==========================================================================
   Meta-Alignment @ AAAI-27 — site styles
   Palette after socialnav2026 (navy + teal); interaction after Eventix.
   ========================================================================== */

:root {
  --brand: #133190;
  --brand-600: #0f2773;
  --brand-900: #0b1a55;
  --brand-rgb: 19, 49, 144;
  --accent: #00d1b2;
  --accent-ink: #053a33;
  --ink: #1d2340;
  --text: #3d4260;
  --muted: #6b7190;
  --line: #e3e7f2;
  --bg: #ffffff;
  --bg-alt: #f5f7fb;
  --surface: #ffffff;
  --radius: 16px;
  --shadow-sm: 0 2px 10px rgba(var(--brand-rgb), .06);
  --shadow: 0 12px 32px rgba(var(--brand-rgb), .10);
  --shadow-lg: 0 24px 60px rgba(var(--brand-rgb), .18);
  --header-h: 72px;
  --font-body: "Roboto", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-head: "Rubik", system-ui, -apple-system, "Segoe UI", sans-serif;
  --ease: cubic-bezier(.2, .7, .2, 1);
}

html { scroll-padding-top: calc(var(--header-h) + 8px); }
/* `clip`, not `hidden`: hidden turns <body> into a scroll container, which
   breaks in-page anchors and Bootstrap ScrollSpy (the window must scroll). */
html, body { overflow-x: clip; }
body {
  font-family: var(--font-body);
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
}
h1, h2, h3, h4, h5, h6 { font-family: var(--font-head); color: var(--ink); }
a { color: var(--brand); text-decoration: none; transition: color .2s; }
a:hover { color: color-mix(in srgb, var(--brand), var(--accent) 45%); }
::selection { background: rgba(0, 209, 178, .3); }

/* ---------- Buttons ---------- */
.btn { border-radius: 999px; font-weight: 500; padding: .65rem 1.4rem; transition: transform .25s var(--ease), box-shadow .25s, background .25s, color .25s; }
.btn-lg { padding: .85rem 1.8rem; font-size: 1.02rem; }
.btn-accent { background: var(--accent); color: var(--accent-ink); border: 0; }
.btn-accent:hover, .btn-accent:focus-visible { background: #1ee6c8; color: var(--accent-ink); transform: translateY(-2px); box-shadow: 0 10px 24px rgba(0, 209, 178, .35); }
.btn-ghost { color: #fff; border: 1.5px solid rgba(255, 255, 255, .5); background: rgba(255, 255, 255, .06); backdrop-filter: blur(6px); }
.btn-ghost:hover { color: var(--brand-900); background: #fff; border-color: #fff; transform: translateY(-2px); }

/* ---------- Header ---------- */
.site-header {
  position: fixed; inset: 0 0 auto 0; z-index: 1030;
  height: var(--header-h);
  display: flex; align-items: center;
  transition: background .35s, box-shadow .35s, height .35s;
}
.site-header .navbar { width: 100%; padding: 0; }
.site-header .navbar > .container { flex-wrap: nowrap; gap: 1rem; }
.navbar-brand { display: flex; align-items: center; gap: .6rem; min-width: 0; margin-right: 0; color: #fff; font-family: var(--font-head); font-weight: 600; font-size: clamp(.9rem, 2.6vw, 1.1rem); line-height: 1.2; }
.navbar-brand img { flex: none; }
/* Long workshop names: up to two lines on small screens, one line with an
   ellipsis on desktop so the menu never wraps. */
.navbar-brand span { min-width: 0; white-space: normal; overflow: hidden; display: -webkit-box; -webkit-box-orient: vertical; -webkit-line-clamp: 2; }
@media (min-width: 1200px) {
  .navbar-brand span { display: block; white-space: nowrap; text-overflow: ellipsis; }
  .site-header .nav-link { padding-left: .55rem !important; padding-right: .55rem !important; }
}
/* The header runs a little wider than page content so long names fit. */
@media (min-width: 1200px) {
  .site-header .navbar > .container { max-width: min(1440px, 100%); }
}
/* Between xl and xxl there is no room for both; the "Submit" menu link stays. */
@media (min-width: 1200px) and (max-width: 1399.98px) {
  .site-header .offcanvas .btn-accent { display: none; }
  .navbar-brand { font-size: 1rem; }
}
.site-header .nav-link, .site-header .btn { white-space: nowrap; }
.navbar-toggler { flex: none; }
.navbar-brand:hover { color: #fff; }
.navbar-toggler { border: 0; color: #fff; font-size: 2rem; padding: 0 .25rem; box-shadow: none !important; }
.site-header .nav-link {
  position: relative; color: rgba(255, 255, 255, .85);
  font-family: var(--font-head); font-weight: 500; font-size: .95rem;
  padding: .5rem .8rem !important;
}
.site-header .nav-link:hover, .site-header .nav-link.active { color: #fff; }
@media (min-width: 1200px) {
  .site-header .nav-link::after {
    content: ""; position: absolute; left: .55rem; right: .55rem; bottom: .15rem; height: 2px;
    background: var(--accent); border-radius: 2px; transform: scaleX(0); transform-origin: left; transition: transform .3s var(--ease);
  }
  .site-header .nav-link:hover::after, .site-header .nav-link.active::after { transform: scaleX(1); }
}
.site-header.scrolled { background: rgba(255, 255, 255, .92); backdrop-filter: saturate(160%) blur(12px); box-shadow: 0 4px 24px rgba(var(--brand-rgb), .08); --header-h: 64px; }
.site-header.scrolled .navbar-brand, .site-header.scrolled .navbar-toggler { color: var(--brand); }
.site-header.scrolled .nav-link { color: var(--text); }
.site-header.scrolled .nav-link:hover, .site-header.scrolled .nav-link.active { color: var(--brand); }

/* Mobile offcanvas menu */
@media (max-width: 1199.98px) {
  .offcanvas { width: min(320px, 86vw) !important; }
  .offcanvas-header { border-bottom: 1px solid var(--line); }
  .offcanvas-title { font-family: var(--font-head); font-weight: 600; color: var(--brand); }
  .site-header .offcanvas .nav-link { color: var(--ink); font-size: 1.05rem; padding: .7rem 0 !important; border-bottom: 1px solid var(--line); }
  .site-header .offcanvas .nav-link.active { color: var(--brand); }
  .offcanvas .btn-accent { width: 100%; }
}

/* ---------- Hero ---------- */
.hero {
  position: relative; overflow: hidden; isolation: isolate;
  min-height: 100vh; min-height: 100svh;
  display: flex; align-items: center;
  padding: calc(var(--header-h) + 3rem) 0 5rem;
  color: #fff;
  background: linear-gradient(135deg, var(--brand-900) 0%, var(--brand) 55%, #2a4fd1 100%);
}
.hero-bg { position: absolute; inset: 0; z-index: -1; }
.hero-grid { position: absolute; inset: 0; width: 100%; height: 100%; fill: rgba(255, 255, 255, .12); }
.orb { position: absolute; border-radius: 50%; filter: blur(60px); opacity: .55; animation: float 16s ease-in-out infinite; }
.orb-1 { width: 42vw; height: 42vw; min-width: 280px; min-height: 280px; background: #00d1b2; top: -12%; right: -10%; opacity: .35; }
.orb-2 { width: 30vw; height: 30vw; min-width: 220px; min-height: 220px; background: #5b7cff; bottom: -15%; left: -8%; animation-delay: -5s; }
.orb-3 { width: 18vw; height: 18vw; min-width: 140px; min-height: 140px; background: #a78bfa; top: 40%; left: 45%; opacity: .3; animation-delay: -10s; }
@keyframes float { 0%, 100% { transform: translate(0, 0) scale(1); } 50% { transform: translate(3%, -4%) scale(1.08); } }

.hero-kicker { display: inline-block; font-family: var(--font-head); font-weight: 500; letter-spacing: .04em; font-size: .9rem; padding: .35rem .9rem; border-radius: 999px; background: rgba(255, 255, 255, .1); border: 1px solid rgba(255, 255, 255, .2); margin-bottom: 1.25rem; }
.hero-kicker a { color: var(--accent); }
.hero-title { color: #fff; font-weight: 700; font-size: clamp(2rem, 5.2vw, 3.6rem); line-height: 1.12; letter-spacing: -.02em; margin-bottom: 1.1rem; }
.hero-tagline { font-size: clamp(1.02rem, 1.8vw, 1.25rem); color: rgba(255, 255, 255, .82); max-width: 40rem; margin-bottom: 1.6rem; }
.hero-meta { list-style: none; padding: 0; margin: 0 0 2rem; display: flex; flex-wrap: wrap; gap: .6rem; }
.hero-meta li { display: inline-flex; align-items: center; gap: .5rem; padding: .45rem .9rem; border-radius: 10px; background: rgba(255, 255, 255, .08); font-size: .95rem; }
.hero-meta i { color: var(--accent); }
.hero-cta { display: flex; flex-wrap: wrap; gap: .8rem; }
.hero-scroll { position: absolute; left: 50%; bottom: 1.5rem; transform: translateX(-50%); color: rgba(255, 255, 255, .7); font-size: 1.6rem; animation: bob 2s ease-in-out infinite; }
.hero-scroll:hover { color: #fff; }
@keyframes bob { 0%, 100% { transform: translate(-50%, 0); } 50% { transform: translate(-50%, 8px); } }

.countdown-card {
  background: rgba(255, 255, 255, .1); border: 1px solid rgba(255, 255, 255, .2);
  backdrop-filter: blur(14px); border-radius: 22px; padding: clamp(1.25rem, 3vw, 2rem);
  box-shadow: 0 30px 60px rgba(0, 0, 0, .2);
}
.countdown-label { font-family: var(--font-head); font-weight: 600; font-size: 1.1rem; margin-bottom: 1rem; }
.countdown { display: grid; grid-template-columns: repeat(4, 1fr); gap: .6rem; }
.countdown > div { background: rgba(255, 255, 255, .1); border-radius: 14px; padding: .8rem .25rem; text-align: center; }
.countdown span { display: block; font-family: var(--font-head); font-weight: 700; font-size: clamp(1.5rem, 4.5vw, 2.4rem); line-height: 1; font-variant-numeric: tabular-nums; }
.countdown small { display: block; margin-top: .35rem; font-size: .72rem; letter-spacing: .08em; text-transform: uppercase; opacity: .75; }
.countdown-foot { margin-top: 1rem; font-size: .92rem; opacity: .85; }
.countdown-foot i { color: var(--accent); margin-right: .3rem; }

/* ---------- Sections ---------- */
.section { padding: clamp(4rem, 9vw, 6.5rem) 0; position: relative; }
.section-tight { padding: 2.5rem 0; }
.section-alt { background: var(--bg-alt); }
.section-title { text-align: center; max-width: 46rem; margin: 0 auto clamp(2rem, 5vw, 3.25rem); }
.section-title.text-start { margin-left: 0; }
.section-title h2 { font-weight: 700; font-size: clamp(1.8rem, 4vw, 2.6rem); letter-spacing: -.01em; margin: .35rem 0 .6rem; }
.section-title p { color: var(--muted); margin: 0; }
.eyebrow { display: inline-block; font-family: var(--font-head); font-weight: 600; font-size: .8rem; letter-spacing: .14em; text-transform: uppercase; color: var(--brand); }
.eyebrow::before { content: ""; display: inline-block; width: 1.6rem; height: 2px; background: var(--accent); vertical-align: middle; margin-right: .6rem; }
.eyebrow-light { color: var(--accent); }
.prose { font-size: 1.05rem; }
.prose > :last-child { margin-bottom: 0; }
.prose strong { color: var(--ink); }
.prose-center { max-width: 48rem; margin: 0 auto; text-align: center; }
.prose-center ul, .prose-center ol { display: inline-block; text-align: left; margin-bottom: 1rem; }
.prose ul { padding-left: 1.2rem; }
.prose li { margin-bottom: .45rem; }

/* About */
.about-facts { display: grid; gap: 1rem; }
.fact { display: flex; gap: 1rem; align-items: center; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 1.1rem 1.25rem; box-shadow: var(--shadow-sm); transition: transform .3s var(--ease), box-shadow .3s; }
.fact:hover { transform: translateX(6px); box-shadow: var(--shadow); }
.fact > i { flex: none; display: grid; place-items: center; width: 48px; height: 48px; border-radius: 12px; background: rgba(var(--brand-rgb), .08); color: var(--brand); font-size: 1.35rem; }
.fact small { display: block; color: var(--muted); font-size: .8rem; text-transform: uppercase; letter-spacing: .06em; }
.fact strong { color: var(--ink); font-family: var(--font-head); font-weight: 600; }

/* News */
.news { display: flex; flex-wrap: wrap; gap: 1rem 2.5rem; align-items: flex-start; }
.news-heading { font-size: 1.15rem; font-weight: 600; margin: 0; white-space: nowrap; color: var(--brand); }
.news-list { flex: 1 1 26rem; list-style: none; margin: 0; padding: 0; }
.news-list li { display: flex; gap: 1rem; padding: .5rem 0; border-bottom: 1px dashed var(--line); }
.news-list li:last-child { border-bottom: 0; }
.news-list time { flex: none; font-family: var(--font-head); font-weight: 500; color: var(--muted); font-size: .9rem; min-width: 6.5rem; padding-top: .1rem; }

/* Timeline */
.timeline { list-style: none; margin: 0 auto; padding: 0; max-width: 44rem; position: relative; }
.timeline::before { content: ""; position: absolute; left: 21px; top: 8px; bottom: 8px; width: 2px; background: linear-gradient(var(--brand), var(--accent)); opacity: .25; }
.timeline-item { position: relative; display: flex; gap: 1.25rem; margin-bottom: 1.1rem; }
.timeline-dot { flex: none; z-index: 1; display: grid; place-items: center; width: 44px; height: 44px; border-radius: 50%; background: var(--surface); border: 2px solid var(--brand); color: var(--brand); font-size: .95rem; transition: transform .3s var(--ease); }
.timeline-card { flex: 1; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 1rem 1.3rem; box-shadow: var(--shadow-sm); transition: transform .3s var(--ease), box-shadow .3s; }
.timeline-item:hover .timeline-card { transform: translateY(-3px); box-shadow: var(--shadow); }
.timeline-item:hover .timeline-dot { transform: scale(1.1); }
.timeline-date { font-family: var(--font-head); font-weight: 600; color: var(--brand); }
.timeline-date s { color: var(--muted); font-weight: 400; }
.timeline-label { font-size: 1.08rem; color: var(--ink); font-weight: 500; }
.timeline-note { font-size: .9rem; color: var(--muted); }
.timeline-item.is-next .timeline-dot { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); box-shadow: 0 0 0 6px rgba(0, 209, 178, .2); }
.timeline-item.is-next .timeline-card { border-color: var(--accent); }
.timeline-item.is-event .timeline-dot { background: var(--brand); color: #fff; }
.timeline-item.is-past { opacity: .55; }
.timeline-item.is-past .timeline-date, .timeline-item.is-past .timeline-label { text-decoration: line-through; text-decoration-color: rgba(0, 0, 0, .35); }

/* CFP */
.topic-card { height: 100%; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 1.6rem; transition: transform .35s var(--ease), box-shadow .35s, border-color .35s; position: relative; overflow: hidden; }
.topic-card::after { content: ""; position: absolute; inset: auto 0 0 0; height: 3px; background: linear-gradient(90deg, var(--brand), var(--accent)); transform: scaleX(0); transform-origin: left; transition: transform .4s var(--ease); }
.topic-card:hover { transform: translateY(-6px); box-shadow: var(--shadow); border-color: transparent; }
.topic-card:hover::after { transform: scaleX(1); }
.topic-icon { display: grid; place-items: center; width: 54px; height: 54px; border-radius: 14px; margin-bottom: 1rem; background: linear-gradient(135deg, var(--brand), #3659d6); color: #fff; font-size: 1.5rem; transition: transform .35s var(--ease); }
.topic-card:hover .topic-icon { transform: rotate(-8deg) scale(1.06); }
.topic-card h3 { font-size: 1.12rem; font-weight: 600; margin-bottom: .4rem; }
.topic-card p { margin: 0; color: var(--muted); font-size: .96rem; }
.format-card { height: 100%; text-align: center; border-radius: var(--radius); padding: 1.6rem; background: var(--surface); border: 2px dashed rgba(var(--brand-rgb), .25); }
.format-pages { display: inline-block; font-family: var(--font-head); font-weight: 600; font-size: .85rem; padding: .25rem .8rem; border-radius: 999px; background: rgba(0, 209, 178, .15); color: #04796a; margin-bottom: .6rem; }
.format-card h3 { font-size: 1.2rem; font-weight: 600; }
.format-card p { margin: 0; color: var(--muted); }

/* Submission CTA */
.section-cta { color: rgba(255, 255, 255, .88); background: radial-gradient(circle at 85% 20%, rgba(0, 209, 178, .35), transparent 45%), linear-gradient(135deg, var(--brand-900), var(--brand)); }
.section-cta h2 { color: #fff; font-weight: 700; font-size: clamp(1.8rem, 4vw, 2.5rem); margin: .35rem 0 1.25rem; }
.prose-light strong { color: #fff; }
.prose-light a { color: var(--accent); }
.prose-light ul { list-style: none; padding: 0; }
.prose-light li { position: relative; padding-left: 1.8rem; }
.prose-light li::before { content: "\F26E"; font-family: "bootstrap-icons"; position: absolute; left: 0; top: .05rem; color: var(--accent); }
.submit-box { display: inline-block; width: 100%; max-width: 26rem; padding: 2rem; border-radius: 22px; background: rgba(255, 255, 255, .08); border: 1px solid rgba(255, 255, 255, .18); text-align: center; }
.submit-box > i { font-size: 2.8rem; color: var(--accent); display: block; margin-bottom: .6rem; }
.submit-box a:not(.btn) { color: #fff; text-decoration: underline; }
.submit-box .btn-light { color: var(--brand); font-weight: 600; }
.submit-box .btn-light:hover { transform: translateY(-2px); box-shadow: 0 10px 24px rgba(0, 0, 0, .25); }

/* Speakers */
.speaker-card { height: 100%; background: var(--surface); border-radius: 20px; overflow: hidden; box-shadow: var(--shadow-sm); border: 1px solid var(--line); transition: transform .4s var(--ease), box-shadow .4s; }
.speaker-card:hover { transform: translateY(-8px); box-shadow: var(--shadow-lg); }
.speaker-photo { position: relative; display: block; width: 100%; aspect-ratio: 1 / 1; border: 0; padding: 0; overflow: hidden; cursor: pointer; background: linear-gradient(135deg, var(--brand), #3a64e0 60%, var(--accent)); }
.speaker-photo img { width: 100%; height: 100%; object-fit: cover; transition: transform .6s var(--ease); }
.speaker-card:hover .speaker-photo img { transform: scale(1.08); }
.avatar-initials { display: grid; place-items: center; width: 100%; height: 100%; font-family: var(--font-head); font-weight: 700; color: rgba(255, 255, 255, .92); font-size: clamp(2.5rem, 8vw, 4rem); letter-spacing: .02em; transition: transform .6s var(--ease); }
.speaker-card:hover .avatar-initials { transform: scale(1.08); }
.speaker-more { position: absolute; right: 1rem; bottom: 1rem; display: grid; place-items: center; width: 44px; height: 44px; border-radius: 50%; background: #fff; color: var(--brand); font-size: 1.2rem; box-shadow: var(--shadow); transform: translateY(12px) scale(.8); opacity: 0; transition: all .35s var(--ease); }
.speaker-card:hover .speaker-more, .speaker-photo:focus-visible .speaker-more { transform: none; opacity: 1; }
@media (hover: none) { .speaker-more { transform: none; opacity: 1; } }
.badge-tbc { position: absolute; left: 1rem; top: 1rem; font-size: .75rem; font-weight: 500; padding: .25rem .6rem; border-radius: 999px; background: rgba(0, 0, 0, .45); color: #fff; }
.speaker-body { padding: 1.2rem 1.3rem 1.4rem; }
.speaker-body h3 { font-size: 1.15rem; font-weight: 600; margin-bottom: .15rem; }
.speaker-body h3 a { color: var(--ink); }
.speaker-body h3 a:hover { color: var(--brand); }
.speaker-aff { color: var(--muted); font-size: .92rem; margin-bottom: .6rem; }
.speaker-talk { font-style: italic; color: var(--text); font-size: .95rem; margin-bottom: .75rem; }
.speaker-links { display: flex; gap: .5rem; }
.speaker-links a { display: grid; place-items: center; width: 34px; height: 34px; border-radius: 50%; background: rgba(var(--brand-rgb), .08); color: var(--brand); transition: background .25s, color .25s, transform .25s; }
.speaker-links a:hover { background: var(--brand); color: #fff; transform: translateY(-2px); }
.modal-content { border: 0; border-radius: 20px; }
.modal-header { border-bottom-color: var(--line); padding: 1.25rem 1.5rem; }
.modal-body { padding: 1.5rem; }
.modal-avatar { flex: none; width: 56px; height: 56px; border-radius: 50%; overflow: hidden; display: grid; place-items: center; background: linear-gradient(135deg, var(--brand), var(--accent)); color: #fff; font-family: var(--font-head); font-weight: 700; }
.modal-avatar img { width: 100%; height: 100%; object-fit: cover; }

/* Schedule */
.schedule-tabs { gap: .5rem; margin-bottom: 2rem; }
.schedule-tabs .nav-link { border-radius: 999px; padding: .6rem 1.6rem; color: var(--brand); background: var(--surface); border: 1px solid var(--line); font-family: var(--font-head); font-weight: 500; }
.schedule-tabs .nav-link.active { background: var(--brand); color: #fff; border-color: var(--brand); box-shadow: 0 8px 20px rgba(var(--brand-rgb), .25); }
.schedule-list { max-width: 52rem; margin: 0 auto; display: grid; gap: .8rem; }
.schedule-item { --kind: var(--brand); display: grid; grid-template-columns: 8.5rem 1fr; background: var(--surface); border-radius: 14px; border: 1px solid var(--line); border-left: 4px solid var(--kind); overflow: hidden; transition: transform .3s var(--ease), box-shadow .3s; }
.schedule-item:hover { transform: translateX(4px); box-shadow: var(--shadow); }
.schedule-time { padding: 1rem 1.2rem; font-family: var(--font-head); font-weight: 600; color: var(--ink); background: color-mix(in srgb, var(--kind) 7%, transparent); font-variant-numeric: tabular-nums; }
.schedule-time span { display: block; font-weight: 400; color: var(--muted); font-size: .88rem; }
.schedule-main { padding: 1rem 1.2rem; }
.schedule-main h3 { font-size: 1.05rem; font-weight: 600; margin: .15rem 0 0; }
.schedule-speaker, .schedule-note { margin: .2rem 0 0; color: var(--muted); font-size: .92rem; }
.kind-badge { display: inline-block; font-size: .7rem; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; color: var(--kind); }
.kind-talk { --kind: #133190; }
.kind-contributed { --kind: #6d4bd8; }
.kind-panel { --kind: #d9480f; }
.kind-poster { --kind: #0b8f7c; }
.kind-break { --kind: #9aa1b9; }
.kind-opening { --kind: #c49000; }
@media (max-width: 575.98px) {
  .schedule-item { grid-template-columns: 1fr; }
  .schedule-time { padding: .6rem 1rem; display: flex; gap: .4rem; align-items: baseline; }
  .schedule-time span { display: inline; }
  .schedule-main { padding: .75rem 1rem 1rem; }
}

/* Papers */
.paper-tools { max-width: 56rem; margin: 0 auto 1.5rem; display: grid; gap: 1rem; }
.paper-search { position: relative; }
.paper-search i { position: absolute; left: 1.1rem; top: 50%; transform: translateY(-50%); color: var(--muted); }
.paper-search .form-control { border-radius: 999px; padding: .85rem 1.2rem .85rem 2.8rem; border-color: var(--line); box-shadow: var(--shadow-sm); }
.paper-search .form-control:focus { border-color: var(--brand); box-shadow: 0 0 0 .25rem rgba(var(--brand-rgb), .12); }
.paper-tags { display: flex; flex-wrap: wrap; gap: .5rem; justify-content: center; }
.tag-chip { border: 1px solid var(--line); background: var(--surface); color: var(--text); border-radius: 999px; padding: .35rem 1rem; font-size: .9rem; transition: all .2s; }
.tag-chip:hover { border-color: var(--brand); color: var(--brand); }
.tag-chip.active { background: var(--brand); border-color: var(--brand); color: #fff; }
.paper-list { list-style: none; padding: 0; margin: 0 auto; max-width: 56rem; counter-reset: paper; }
.paper { counter-increment: paper; position: relative; padding: 1.2rem 1.4rem 1.2rem 3.6rem; border: 1px solid var(--line); border-radius: var(--radius); margin-bottom: .8rem; background: var(--surface); transition: box-shadow .3s, border-color .3s; }
.paper::before { content: counter(paper); position: absolute; left: 1.2rem; top: 1.25rem; font-family: var(--font-head); font-weight: 700; color: rgba(var(--brand-rgb), .3); font-size: 1.15rem; }
.paper:hover { box-shadow: var(--shadow); border-color: transparent; }
.paper-head { display: flex; flex-wrap: wrap; gap: .5rem 1rem; justify-content: space-between; align-items: flex-start; }
.paper h3 { font-size: 1.08rem; font-weight: 600; margin: 0; flex: 1 1 20rem; }
.paper-badges { display: flex; gap: .4rem; }
.badge-award { background: #fff4d6; color: #8a5a00; font-weight: 600; }
.badge-track { background: rgba(var(--brand-rgb), .08); color: var(--brand); font-weight: 600; }
.paper-authors { color: var(--muted); margin: .35rem 0 .6rem; font-size: .95rem; }
.paper-links { display: flex; flex-wrap: wrap; gap: .4rem .9rem; align-items: center; font-size: .9rem; }
.paper-links a { font-weight: 500; }
.paper-tag { font-size: .78rem; padding: .1rem .55rem; border-radius: 6px; background: var(--bg-alt); color: var(--muted); }
.paper.is-hidden { display: none; }

.empty-state { text-align: center; color: var(--muted); padding: 2.5rem 1rem; border: 2px dashed var(--line); border-radius: var(--radius); max-width: 36rem; margin: 0 auto; }
.empty-state > i { font-size: 2rem; display: block; margin-bottom: .5rem; color: rgba(var(--brand-rgb), .4); }
.empty-state p { margin: 0; }

/* Organizers */
.organizer { text-align: center; }
.organizer-photo { width: min(150px, 100%); aspect-ratio: 1 / 1; margin: 0 auto 1rem; border-radius: 50%; overflow: hidden; background: linear-gradient(135deg, var(--brand), #3a64e0 60%, var(--accent)); box-shadow: 0 0 0 6px var(--surface), 0 0 0 7px var(--line); transition: transform .4s var(--ease), box-shadow .4s; }
.organizer-photo img { width: 100%; height: 100%; object-fit: cover; }
.organizer-photo .avatar-initials { font-size: clamp(1.6rem, 5vw, 2.4rem); }
.organizer:hover .organizer-photo { transform: translateY(-6px); box-shadow: 0 0 0 6px var(--surface), 0 0 0 8px var(--accent), var(--shadow); }
.organizer h3 { font-size: 1.05rem; font-weight: 600; margin-bottom: .1rem; }
.organizer h3 a { color: var(--ink); }
.organizer-aff { color: var(--muted); font-size: .9rem; margin-bottom: .4rem; }
.organizer-role { display: inline-block; font-size: .78rem; font-weight: 500; padding: .15rem .65rem; border-radius: 999px; background: rgba(var(--brand-rgb), .08); color: var(--brand); }

/* ---------- Footer ---------- */
.site-footer { background: var(--brand-900); color: rgba(255, 255, 255, .78); padding: 3rem 0 1.5rem; }
.site-footer a { color: #fff; }
.site-footer a:hover { color: var(--accent); }
.footer-brand { display: flex; gap: 1rem; align-items: center; }
.footer-brand strong { color: #fff; font-family: var(--font-head); font-weight: 600; }
.footer-links { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: .75rem 1.5rem; justify-content: flex-start; }
@media (min-width: 992px) { .footer-links { justify-content: flex-end; } }
.footer-bottom { margin-top: 2rem; padding-top: 1.25rem; border-top: 1px solid rgba(255, 255, 255, .12); font-size: .85rem; text-align: center; opacity: .7; }

/* Back to top */
.scroll-top { position: fixed; right: 1rem; bottom: 1rem; z-index: 1020; display: grid; place-items: center; width: 46px; height: 46px; border-radius: 50%; background: var(--accent); color: var(--accent-ink); font-size: 1.8rem; box-shadow: 0 10px 24px rgba(0, 0, 0, .18); opacity: 0; visibility: hidden; transform: translateY(12px); transition: all .35s var(--ease); }
.scroll-top.active { opacity: 1; visibility: visible; transform: none; }
.scroll-top:hover { color: var(--accent-ink); background: #1ee6c8; transform: translateY(-3px); }

/* ---------- Motion preferences ---------- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
  [data-aos] { opacity: 1 !important; transform: none !important; }
}