:root {
  --bg: #0b1220;
  --panel: #111a2b;
  --panel-2: #16233a;
  --text: #e8eef7;
  --muted: #a9b7c9;
  --line: #253552;
  --accent: #4da3ff;
  --accent-2: #7cc4ff;
  --max-width: 1120px;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.22);
}

/* Additional styles for research archive and paper entries */
@import "research-upgrade.css";
* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
}
body {
  margin: 0;
  background:
    radial-gradient(circle at top right, rgba(77, 163, 255, 0.08), transparent 28%),
    linear-gradient(180deg, #08101c 0%, #0b1220 100%);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.7;
}
a {
  color: var(--accent-2);
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}
.container {
  width: min(100% - 2rem, var(--max-width));
  margin: 0 auto;
}
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(10px);
  background: rgba(8, 16, 28, 0.88);
  border-bottom: 1px solid var(--line);
}
.brand-block {
  padding-top: 1.1rem;
}
.brand {
  display: inline-block;
  font-size: 1.8rem;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--text);
}
.tagline {
  margin: 0.35rem 0 1rem;
  color: var(--muted);
  font-size: 0.96rem;
}
.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  padding-bottom: 1rem;
}
.site-nav a {
  color: var(--text);
  font-weight: 600;
  opacity: 0.92;
}
.site-nav a:hover {
  color: var(--accent-2);
  text-decoration: none;
}
.content {
  padding: 2.5rem 0 4rem;
}
.hero,
.card,
.article-list article,
.paper-note,
.paper-meta,
.panel {
  background: linear-gradient(180deg, rgba(17, 26, 43, 0.95), rgba(12, 21, 35, 0.95));
  border: 1px solid var(--line);
  border-radius: 18px;
  box-shadow: var(--shadow);
}
.hero {
  padding: 2rem;
  margin-bottom: 2rem;
}
.hero h1,
.hero h2 {
  margin-top: 0;
  line-height: 1.2;
  font-size: clamp(2rem, 5vw, 3rem);
}
.hero p {
  max-width: 780px;
  color: var(--muted);
  font-size: 1.05rem;
}
.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  margin-top: 1.4rem;
}
.button {
  display: inline-block;
  padding: 0.78rem 1.1rem;
  border-radius: 10px;
  background: linear-gradient(180deg, var(--accent), #2b87ea);
  color: white;
  font-weight: 700;
}
.button.secondary {
  background: transparent;
  border: 1px solid var(--line);
  color: var(--text);
}
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1rem;
}
.card {
  padding: 1.35rem;
}
.card h3 {
  margin-top: 0;
  margin-bottom: 0.6rem;
}
.card p,
.page-intro,
.meta,
.footer-note {
  color: var(--muted);
}
h1, h2, h3 {
  line-height: 1.25;
}
h1 {
  font-size: clamp(2rem, 5vw, 2.7rem);
}
h2 {
  margin-top: 2rem;
  font-size: 1.7rem;
}
h3 {
  margin-top: 1.4rem;
  font-size: 1.2rem;
}
ul, ol {
  padding-left: 1.25rem;
}
.article-list article {
  padding: 1.35rem;
  margin-bottom: 1rem;
}
.paper {
  max-width: 900px;
  margin: 0 auto;
}
.paper-meta {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 0.9rem;
  padding: 1rem;
  margin: 1rem 0 1.2rem;
}
.paper-note {
  padding: 1rem 1.2rem;
  margin-bottom: 1.2rem;
}
code {
  background: var(--panel-2);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 0.12rem 0.4rem;
}
.site-footer {
  border-top: 1px solid var(--line);
  background: rgba(8, 16, 28, 0.92);
}
.footer-inner {
  padding: 1.5rem 0 2rem;
  text-align: center;
}
.footer-inner p {
  margin: 0.3rem 0;
}
@media (max-width: 700px) {
  .site-nav {
    gap: 0.8rem;
  }
  .hero {
    padding: 1.3rem;
  }
}