/* ===== Reset & Base ===== */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  /* Palette */
  --bg-primary: #0a0b14;
  --bg-secondary: #0f1023;
  --bg-card: rgba(255, 255, 255, 0.04);
  --bg-card-hover: rgba(255, 255, 255, 0.07);
  --glass-border: rgba(255, 255, 255, 0.08);
  --glass-border-hover: rgba(255, 255, 255, 0.15);

  --text-primary: #e8e9f0;
  --text-secondary: #9a9cb8;
  --text-muted: #6b6d8a;

  --accent-1: #6c5ce7;
  --accent-2: #a29bfe;
  --accent-3: #00cec9;
  --accent-gradient: linear-gradient(135deg, #6c5ce7, #a29bfe, #00cec9);

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 28px;

  --shadow-card: 0 4px 30px rgba(0, 0, 0, 0.3);
  --shadow-glow: 0 0 60px rgba(108, 92, 231, 0.15);

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

a {
  color: var(--accent-2);
  text-decoration: none;
  transition: color 0.2s;
}
a:hover { color: var(--accent-3); }

img { max-width: 100%; display: block; }

.container {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== Navbar ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 16px 0;
  transition: background 0.3s, box-shadow 0.3s, padding 0.3s;
}
.navbar.scrolled {
  background: rgba(10, 11, 20, 0.92);
  backdrop-filter: blur(20px);
  box-shadow: 0 1px 0 var(--glass-border);
  padding: 10px 0;
}
.nav-container {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-logo {
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}
.nav-logo .accent { color: var(--accent-2); }
.nav-links {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 32px;
}
.nav-links a {
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
  transition: color 0.2s;
}
.nav-links a:hover { color: var(--text-primary); }
.nav-cta {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-weight: 600 !important;
}
.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  flex-direction: column;
  gap: 5px;
  padding: 4px;
}
.nav-toggle span {
  width: 22px;
  height: 2px;
  background: var(--text-secondary);
  border-radius: 2px;
  transition: transform 0.3s, opacity 0.3s;
}

/* ===== Hero ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 120px 24px 80px;
  overflow: hidden;
}
.hero-bg-shapes {
  position: absolute;
  inset: 0;
  pointer-events: none;
}
.shape {
  position: absolute;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.35;
}
.shape-1 {
  width: 600px;
  height: 600px;
  background: var(--accent-1);
  top: -200px;
  right: -100px;
}
.shape-2 {
  width: 500px;
  height: 500px;
  background: var(--accent-3);
  bottom: -200px;
  left: -100px;
  opacity: 0.2;
}
.shape-3 {
  width: 300px;
  height: 300px;
  background: var(--accent-2);
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  opacity: 0.12;
}

.hero-content {
  position: relative;
  max-width: 820px;
  text-align: center;
}
.hero-badge {
  display: inline-block;
  padding: 8px 20px;
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: 100px;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  letter-spacing: 0.03em;
  margin-bottom: 28px;
  backdrop-filter: blur(10px);
}
.hero-title {
  font-size: clamp(2.2rem, 5vw, 3.6rem);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.03em;
  margin-bottom: 24px;
}
.gradient-text {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-subtitle {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto 36px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 48px;
}

.hero-meta {
  display: flex;
  gap: 32px;
  justify-content: center;
  flex-wrap: wrap;
}
.meta-item {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--text-muted);
  font-size: 0.9rem;
}
.meta-item svg { opacity: 0.6; }

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: var(--radius-md);
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: transform 0.2s, box-shadow 0.2s, background 0.2s;
  text-decoration: none;
}
.btn:hover { transform: translateY(-1px); }

.btn-primary {
  background: var(--accent-gradient);
  color: #fff;
  box-shadow: 0 4px 20px rgba(108, 92, 231, 0.3);
}
.btn-primary:hover {
  box-shadow: 0 6px 30px rgba(108, 92, 231, 0.45);
  color: #fff;
}

.btn-outline {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--glass-border);
}
.btn-outline:hover {
  border-color: var(--glass-border-hover);
  color: var(--text-primary);
  background: var(--bg-card);
}

.btn-lg {
  padding: 18px 36px;
  font-size: 1.05rem;
  border-radius: var(--radius-lg);
}

/* ===== Sections ===== */
.section {
  padding: 100px 0;
}
.section-alt {
  background: var(--bg-secondary);
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}
.section-label {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--accent-2);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 12px;
}
.section-title {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}
.section-desc {
  max-width: 660px;
  margin: 0 auto;
  color: var(--text-secondary);
  font-size: 1.05rem;
}
.section-desc strong { color: var(--accent-3); font-weight: 600; }

/* ===== Pillars ===== */
.pillars-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
  margin-bottom: 48px;
}
.pillar-card {
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  transition: border-color 0.3s, background 0.3s, transform 0.3s;
  backdrop-filter: blur(10px);
}
.pillar-card:hover {
  border-color: var(--glass-border-hover);
  background: var(--bg-card-hover);
  transform: translateY(-4px);
}
.pillar-icon {
  width: 56px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(108, 92, 231, 0.1);
  border-radius: var(--radius-md);
  margin-bottom: 20px;
  color: var(--accent-2);
}
.pillar-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 10px;
}
.pillar-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.65;
}

/* ===== Preprint Link ===== */
.about-preprint {
  max-width: 560px;
  margin: 0 auto;
}
.preprint-link {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 20px 24px;
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  color: var(--text-primary);
  transition: border-color 0.3s, background 0.3s, transform 0.2s;
}
.preprint-link:hover {
  border-color: var(--accent-2);
  background: var(--bg-card-hover);
  transform: translateY(-2px);
  color: var(--text-primary);
}
.preprint-link div { flex: 1; }
.preprint-link strong { display: block; font-size: 0.95rem; }
.preprint-link span { font-size: 0.82rem; color: var(--text-muted); }
.preprint-link > svg:first-child { color: var(--accent-2); flex-shrink: 0; }
.preprint-link > svg:last-child { color: var(--text-muted); flex-shrink: 0; }

/* ===== Topics ===== */
.topics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
}
.topic-card {
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  transition: border-color 0.3s, background 0.3s, transform 0.3s;
}
.topic-card:hover {
  border-color: var(--glass-border-hover);
  background: var(--bg-card-hover);
  transform: translateY(-3px);
}
.topic-number {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--accent-3);
  margin-bottom: 12px;
}
.topic-card h4 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 8px;
}
.topic-card p {
  color: var(--text-secondary);
  font-size: 0.92rem;
  line-height: 1.6;
}

/* ===== Call for Papers ===== */
.cfp-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
  margin-bottom: 40px;
}
.cfp-card {
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  text-align: center;
  transition: border-color 0.3s, transform 0.3s;
}
.cfp-card:hover {
  border-color: var(--glass-border-hover);
  transform: translateY(-3px);
}
.cfp-card-icon {
  font-size: 2rem;
  margin-bottom: 16px;
}
.cfp-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 10px;
}
.cfp-card p {
  color: var(--text-secondary);
  font-size: 0.92rem;
  line-height: 1.6;
}

.cfp-note {
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.95rem;
  max-width: 700px;
  margin: 0 auto 56px;
  padding: 24px 28px;
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
}
.cfp-note strong { color: var(--accent-3); }

/* ===== Timeline ===== */
.timeline {
  max-width: 540px;
  margin: 0 auto 56px;
}
.timeline-title {
  text-align: center;
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 32px;
}
.timeline-items {
  position: relative;
  padding-left: 32px;
}
.timeline-items::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--glass-border);
}
.timeline-item {
  position: relative;
  margin-bottom: 28px;
}
.timeline-item:last-child { margin-bottom: 0; }
.timeline-dot {
  position: absolute;
  left: -28px;
  top: 4px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--bg-primary);
  border: 2px solid var(--text-muted);
}
.timeline-dot.active {
  border-color: var(--accent-1);
  background: var(--accent-1);
  box-shadow: 0 0 12px rgba(108, 92, 231, 0.5);
}
.timeline-date {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--accent-2);
  margin-bottom: 2px;
}
.timeline-label {
  font-size: 0.95rem;
  color: var(--text-secondary);
}

/* ===== Submit CTA ===== */
.submit-cta {
  text-align: center;
}
.submit-hint {
  margin-top: 12px;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ===== Schedule ===== */
.schedule-table-wrap {
  overflow-x: auto;
  border-radius: var(--radius-lg);
  border: 1px solid var(--glass-border);
  background: var(--bg-card);
}
.schedule-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
}
.schedule-table th {
  padding: 16px 24px;
  text-align: left;
  font-weight: 600;
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  border-bottom: 1px solid var(--glass-border);
}
.schedule-table td {
  padding: 16px 24px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.03);
}
.schedule-table tr:last-child td { border-bottom: none; }
.schedule-table tr:hover td { background: rgba(255, 255, 255, 0.02); }
.time-cell {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--accent-2);
  white-space: nowrap;
  width: 160px;
}
.break-row td {
  background: rgba(108, 92, 231, 0.04);
  color: var(--text-muted);
  font-style: italic;
}
.schedule-table em { color: var(--accent-3); font-style: italic; }

/* ===== Organizers ===== */
.organizers-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px;
}
.organizer-card {
  background: var(--bg-card);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  text-align: center;
  transition: border-color 0.3s, transform 0.3s;
}
.organizer-card:hover {
  border-color: var(--glass-border-hover);
  transform: translateY(-4px);
}
.organizer-img-wrap {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  margin: 0 auto 20px;
  overflow: hidden;
  border: 2px solid var(--glass-border);
  transition: border-color 0.3s;
}
.organizer-card:hover .organizer-img-wrap {
  border-color: var(--accent-2);
}
.organizer-img-wrap img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.organizer-card h4 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 4px;
}
.organizer-affiliation {
  display: block;
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--accent-2);
  margin-bottom: 10px;
}
.organizer-bio {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.55;
}

/* ===== Footer ===== */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--glass-border);
  padding: 60px 0 32px;
}
.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}
.footer-logo {
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--text-primary);
}
.footer-logo .accent { color: var(--accent-2); }
.footer-brand p {
  margin-top: 12px;
  color: var(--text-muted);
  font-size: 0.9rem;
  max-width: 360px;
}
.footer-links h4 {
  font-size: 0.82rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: 16px;
}
.footer-links a {
  display: block;
  color: var(--text-secondary);
  font-size: 0.9rem;
  padding: 4px 0;
}
.footer-links a:hover { color: var(--text-primary); }
.footer-bottom {
  border-top: 1px solid var(--glass-border);
  padding-top: 24px;
  text-align: center;
}
.footer-bottom p {
  font-size: 0.85rem;
  color: var(--text-muted);
}
.footer-bottom a { color: var(--accent-2); }

/* ===== Animations ===== */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }
  .nav-links {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    flex-direction: column;
    background: rgba(10, 11, 20, 0.98);
    backdrop-filter: blur(20px);
    padding: 80px 32px 32px;
    gap: 24px;
    transition: right 0.4s ease;
    border-left: 1px solid var(--glass-border);
  }
  .nav-links.open { right: 0; }

  .hero { min-height: auto; padding: 140px 20px 80px; }
  .hero-title { font-size: clamp(1.8rem, 6vw, 2.8rem); }

  .section { padding: 64px 0; }

  .footer-content {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .pillars-grid,
  .topics-grid,
  .cfp-grid {
    grid-template-columns: 1fr;
  }

  .organizers-grid {
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  }
}
