/* =====================================================
   SecureRouter — Paper Website CSS
   ===================================================== */

:root {
  --primary:       #6366f1;
  --primary-dark:  #4f46e5;
  --primary-glow:  rgba(99, 102, 241, 0.35);
  --accent:        #22d3ee;
  --accent-dark:   #0891b2;
  --bg:            #0a0a12;
  --bg-card:       rgba(255,255,255,0.04);
  --bg-card-hover: rgba(255,255,255,0.07);
  --border:        rgba(255,255,255,0.08);
  --text:          #e2e8f0;
  --text-muted:    #94a3b8;
  --text-strong:   #f8fafc;
  --radius:        16px;
  --radius-sm:     10px;
  --shadow:        0 8px 40px rgba(0,0,0,0.5);
  --font:          'Inter', system-ui, sans-serif;
  --mono:          'JetBrains Mono', monospace;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  font-size: 16px;
  line-height: 1.75;
  overflow-x: hidden;
}

a { color: var(--accent); text-decoration: none; transition: color .2s; }
a:hover { color: #fff; }

/* ======== NAVBAR ======== */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: rgba(10,10,18,0.85);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
  padding: 0 2rem;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.navbar-brand, .navbar-menu { display: flex; align-items: center; }

.brand-name {
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--text-strong) !important;
  letter-spacing: -0.02em;
  display: flex;
  align-items: center;
  gap: 8px;
}
.lock-icon { font-size: 1.1rem; }

.navbar-end { display: flex; align-items: center; gap: 4px; }
.navbar-item {
  color: var(--text-muted) !important;
  font-size: 0.875rem;
  font-weight: 500;
  padding: 6px 14px;
  border-radius: 8px;
  transition: color .2s, background .2s;
}
.navbar-item:hover {
  color: var(--text-strong) !important;
  background: var(--bg-card);
}

.navbar-burger { display: none; }

/* ======== HERO ======== */
.hero-section {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 120px 2rem 80px;
  overflow: hidden;
}

.hero-bg-grid {
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(99,102,241,0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(99,102,241,0.06) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse 80% 60% at 50% 50%, #000 40%, transparent 100%);
}

.hero-bg-glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.35;
  pointer-events: none;
}
.glow-1 {
  width: 600px; height: 600px;
  background: radial-gradient(circle, #6366f1, transparent 70%);
  top: -100px; left: -100px;
  animation: driftA 12s ease-in-out infinite alternate;
}
.glow-2 {
  width: 500px; height: 500px;
  background: radial-gradient(circle, #22d3ee, transparent 70%);
  bottom: -100px; right: -100px;
  animation: driftB 14s ease-in-out infinite alternate;
}

@keyframes driftA { from { transform: translate(0,0); } to { transform: translate(60px, 40px); } }
@keyframes driftB { from { transform: translate(0,0); } to { transform: translate(-50px, -30px); } }

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 860px;
}

.venue-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(99,102,241,0.15);
  border: 1px solid rgba(99,102,241,0.35);
  color: #a5b4fc;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 6px 18px;
  border-radius: 100px;
  margin-bottom: 2rem;
  animation: fadeUp 0.6s ease both;
}
.badge-dot {
  width: 7px; height: 7px;
  border-radius: 50%;
  background: #6366f1;
  box-shadow: 0 0 8px #6366f1;
  animation: pulse 2s infinite;
}
@keyframes pulse {
  0%, 100% { box-shadow: 0 0 6px #6366f1; }
  50% { box-shadow: 0 0 16px #6366f1, 0 0 30px rgba(99,102,241,0.5); }
}

.paper-title {
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 800;
  line-height: 1.18;
  color: var(--text-strong);
  letter-spacing: -0.03em;
  margin-bottom: 1.5rem;
  animation: fadeUp 0.6s 0.1s ease both;
}
.title-accent {
  background: linear-gradient(135deg, #818cf8, #22d3ee);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.authors-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
  margin-bottom: 0.4rem;
  animation: fadeUp 0.6s 0.2s ease both;
}
.author-link {
  color: #c7d2fe;
  font-weight: 500;
  font-size: 1.05rem;
  transition: color .2s;
}
.author-link:hover { color: #fff; text-decoration: underline; }
.author-sep { color: var(--text-muted); }

.affiliation {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 2.5rem;
  animation: fadeUp 0.6s 0.25s ease both;
}

/* Hero Buttons */
.hero-buttons {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-bottom: 3rem;
  animation: fadeUp 0.6s 0.3s ease both;
}

.hero-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: 100px;
  font-weight: 600;
  font-size: 0.9rem;
  letter-spacing: 0.02em;
  transition: transform .2s, box-shadow .2s, background .2s;
  cursor: pointer;
}
.hero-btn:hover { transform: translateY(-2px); }

.btn-paper {
  background: linear-gradient(135deg, #6366f1, #4f46e5);
  color: #fff !important;
  box-shadow: 0 4px 20px rgba(99,102,241,0.45);
}
.btn-paper:hover { box-shadow: 0 6px 28px rgba(99,102,241,0.65); }

.btn-github {
  background: rgba(255,255,255,0.08);
  border: 1px solid var(--border);
  color: var(--text) !important;
}
.btn-github:hover { background: rgba(255,255,255,0.14); color: #fff !important; }

.btn-demo {
  background: linear-gradient(135deg, #0ea5e9, #22d3ee);
  color: #fff !important;
  box-shadow: 0 4px 20px rgba(34,211,238,0.35);
}
.btn-demo:hover { box-shadow: 0 6px 28px rgba(34,211,238,0.55); }

.btn-docs {
  background: rgba(255,255,255,0.08);
  border: 1px solid var(--border);
  color: var(--text) !important;
}
.btn-docs:hover { background: rgba(255,255,255,0.14); color: #fff !important; }

/* Stats Bar */
.stats-bar {
  display: inline-flex;
  align-items: center;
  gap: 2rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 16px 36px;
  border-radius: var(--radius);
  animation: fadeUp 0.6s 0.4s ease both;
}
.stat-item { text-align: center; }
.stat-number {
  display: block;
  font-size: 1.6rem;
  font-weight: 800;
  background: linear-gradient(135deg, #818cf8, #22d3ee);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.1;
}
.stat-label {
  display: block;
  font-size: 0.72rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-top: 2px;
}
.stat-divider {
  width: 1px;
  height: 40px;
  background: var(--border);
}

/* ======== SECTIONS ======== */
.content-section {
  padding: 100px 2rem;
}
.alt-bg { background: rgba(255,255,255,0.015); }

.container { max-width: 1200px; margin: 0 auto; }
.container.narrow { max-width: 780px; }

.section-title {
  font-size: 2rem;
  font-weight: 800;
  color: var(--text-strong);
  text-align: center;
  letter-spacing: -0.03em;
  margin-bottom: 12px;
}
.section-underline {
  width: 48px;
  height: 4px;
  border-radius: 2px;
  background: linear-gradient(90deg, #6366f1, #22d3ee);
  margin: 0 auto 2.5rem;
}

/* ======== ABSTRACT ======== */
.abstract-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2.5rem 3rem;
}
.abstract-text {
  color: var(--text);
  font-size: 1.02rem;
  line-height: 1.85;
  margin-bottom: 1.2rem;
}
.abstract-text:last-child { margin-bottom: 0; }
.abstract-text strong { color: #a5b4fc; }
.abstract-text em { color: #67e8f9; font-style: italic; }

/* ======== CONTRIBUTIONS ======== */
.contributions-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.contribution-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2rem;
  transition: transform .25s, box-shadow .25s, background .25s, border-color .25s;
  cursor: default;
}
.contribution-card:hover {
  transform: translateY(-4px);
  background: var(--bg-card-hover);
  border-color: rgba(99,102,241,0.3);
  box-shadow: 0 12px 40px rgba(99,102,241,0.15);
}

.card-icon {
  width: 52px; height: 52px;
  border-radius: 14px;
  background: linear-gradient(135deg, rgba(99,102,241,0.2), rgba(34,211,238,0.1));
  border: 1px solid rgba(99,102,241,0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  color: #818cf8;
  margin-bottom: 1.2rem;
}

.card-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-strong);
  margin-bottom: 0.6rem;
  letter-spacing: -0.01em;
}

.card-text {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ======== DEMO ======== */
.demo-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 3rem;
  text-align: center;
}
.demo-icon-wrap {
  width: 72px; height: 72px;
  border-radius: 50%;
  background: linear-gradient(135deg, #6366f1, #22d3ee);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
  color: #fff;
  margin: 0 auto 1.5rem;
  box-shadow: 0 8px 30px rgba(99,102,241,0.4);
}
.demo-title {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-strong);
  margin-bottom: 0.8rem;
}
.demo-text {
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  max-width: 480px;
  margin-left: auto;
  margin-right: auto;
}
.demo-buttons {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}
.demo-btn.disabled { opacity: 0.5; pointer-events: none; }

/* ======== DOCS ======== */
.docs-grid {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.docs-card {
  display: flex;
  align-items: center;
  gap: 1.2rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 1.2rem 1.5rem;
  color: var(--text) !important;
  transition: transform .2s, border-color .2s, background .2s;
}
.docs-card:hover {
  transform: translateX(4px);
  border-color: rgba(99,102,241,0.4);
  background: var(--bg-card-hover);
}
.docs-card.disabled { opacity: 0.5; pointer-events: none; }
.docs-card-icon {
  width: 44px; height: 44px;
  border-radius: 10px;
  background: rgba(99,102,241,0.15);
  border: 1px solid rgba(99,102,241,0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  color: #818cf8;
  flex-shrink: 0;
}
.docs-card-body { flex: 1; }
.docs-card-title { font-weight: 600; color: var(--text-strong); font-size: 0.95rem; }
.docs-card-desc { font-size: 0.82rem; color: var(--text-muted); margin-top: 2px; }
.docs-arrow { color: var(--text-muted); font-size: 0.85rem; }

/* ======== CITATION ======== */
.citation-intro {
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  text-align: center;
}

.bibtex-block {
  background: #0d0d1a;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}
.bibtex-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 18px;
  background: rgba(99,102,241,0.08);
  border-bottom: 1px solid var(--border);
}
.bibtex-label {
  font-size: 0.78rem;
  font-weight: 700;
  color: #818cf8;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}
.copy-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(99,102,241,0.15);
  border: 1px solid rgba(99,102,241,0.3);
  color: #a5b4fc;
  border-radius: 6px;
  padding: 4px 14px;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  font-family: var(--font);
  transition: background .2s, color .2s;
}
.copy-btn:hover { background: rgba(99,102,241,0.3); color: #fff; }
.copy-btn.copied { background: rgba(34,197,94,0.2); border-color: rgba(34,197,94,0.4); color: #86efac; }

.bibtex-code {
  font-family: var(--mono);
  font-size: 0.82rem;
  line-height: 1.8;
  color: #93c5fd;
  padding: 1.5rem 1.8rem;
  overflow-x: auto;
  white-space: pre;
  background: transparent;
}

/* ======== COMING SOON TAG ======== */
.coming-soon-tag {
  font-size: 0.78rem;
  color: var(--text-muted);
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 2px 8px;
}

/* ======== FOOTER ======== */
.site-footer {
  background: rgba(0,0,0,0.4);
  border-top: 1px solid var(--border);
  padding: 2.5rem 2rem;
  text-align: center;
}
.footer-inner { display: flex; flex-direction: column; gap: 6px; }
.footer-text { font-size: 0.82rem; color: var(--text-muted); }
.footer-text a { color: var(--accent); }
.footer-text a:hover { color: #fff; }

/* ======== ANIMATIONS ======== */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ======== RESPONSIVE ======== */
@media (max-width: 960px) {
  .contributions-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
  .navbar-item { display: none; }
  .navbar-burger { display: flex; }
  .contributions-grid { grid-template-columns: 1fr; }
  .stats-bar { flex-direction: column; gap: 1rem; padding: 1.2rem 2rem; }
  .stat-divider { width: 40px; height: 1px; }
  .abstract-card { padding: 1.5rem; }
  .paper-title { font-size: 1.7rem; }
  .hero-buttons { gap: 8px; }
  .hero-btn { padding: 10px 18px; font-size: 0.82rem; }
}