/* Stars 2.0 / Stele — Deep Space Astronomy Stylesheet */
:root {
  --space-bg: #04060a;
  --panel-bg: #0c1017;
  --card-bg: #121822;
  --text: #e2e8f4;
  --text-muted: #8b99ad;
  --cyan: #38bdf8;
  --azure: #0284c7;
  --border: rgba(56, 189, 248, 0.2);
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  margin: 0;
  padding: 20px 10px;
  background-color: var(--space-bg);
  background-image: radial-gradient(ellipse at top, #0f1c2e 0%, var(--space-bg) 70%);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  line-height: 1.6;
}

.site-container {
  max-width: 960px;
  margin: 0 auto;
  background: var(--panel-bg);
  border: 1px solid var(--border);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.9);
  border-radius: 6px;
  overflow: hidden;
}

/* Masthead */
.masthead {
  background: #000000;
  border-bottom: 2px solid var(--azure);
}

.banner {
  position: relative;
  height: 190px;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.banner-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: brightness(0.7) contrast(1.1);
}

.banner-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: linear-gradient(180deg, rgba(0,0,0,0.3) 0%, rgba(4,6,10,0.85) 100%);
  text-align: center;
  padding: 0 20px;
}

.logo-title {
  margin: 0;
  font-size: clamp(2.2rem, 5vw, 3.4rem);
  font-weight: 800;
  letter-spacing: 0.25em;
  color: #ffffff;
  text-shadow: 0 0 20px rgba(56, 189, 248, 0.7);
}

.tagline {
  margin: 6px 0 0;
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  color: var(--cyan);
  font-weight: 600;
}

.top-nav {
  display: flex;
  background: #080d14;
  border-top: 1px solid var(--border);
  flex-wrap: wrap;
}

.nav-link {
  flex: 1;
  min-width: 100px;
  padding: 12px 14px;
  text-align: center;
  color: #94a3b8;
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 600;
  border-right: 1px solid rgba(255, 255, 255, 0.05);
  transition: all 0.2s ease;
}

.nav-link:hover {
  background: rgba(56, 189, 248, 0.12);
  color: #ffffff;
}

.nav-link.active {
  background: var(--azure);
  color: #ffffff;
}

/* Content */
.content-body {
  padding: 30px;
}

.quote-bar {
  background: #06090e;
  border-left: 3px solid var(--cyan);
  padding: 16px 20px;
  margin-bottom: 30px;
  border-radius: 0 4px 4px 0;
}

.quote-bar blockquote {
  margin: 0 0 6px;
  font-style: italic;
  font-size: 0.94rem;
  color: #c7d2e0;
}

.quote-bar cite {
  font-size: 0.8rem;
  color: var(--cyan);
  font-weight: 600;
}

.section {
  margin-bottom: 40px;
  scroll-margin-top: 20px;
}

.section h2 {
  font-size: 1.35rem;
  color: #ffffff;
  border-bottom: 1px solid var(--border);
  padding-bottom: 8px;
  margin-top: 0;
  margin-bottom: 18px;
  letter-spacing: 0.04em;
}

.topic-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 24px;
  align-items: center;
}

.topic-text h3 {
  color: var(--cyan);
  font-size: 1.1rem;
  margin: 0 0 6px;
}

.topic-text p {
  margin: 0 0 16px;
  color: var(--text-muted);
  font-size: 0.94rem;
}

.supernova-fig {
  margin: 0;
  background: #000000;
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 10px;
  text-align: center;
}

.nebula-img {
  width: 100%;
  height: auto;
  border-radius: 2px;
}

.supernova-fig figcaption {
  margin-top: 8px;
  font-size: 0.78rem;
  color: var(--cyan);
}

/* Spectral Table */
.spectral-table-wrap {
  overflow-x: auto;
  border: 1px solid var(--border);
  border-radius: 4px;
}

.spectral-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
}

.spectral-table th {
  background: #090e16;
  color: var(--cyan);
  padding: 10px 14px;
  text-align: left;
  border-bottom: 1px solid var(--border);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
}

.spectral-table td {
  padding: 10px 14px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
  color: var(--text-muted);
}

.spectral-table tr:hover td {
  background: rgba(56, 189, 248, 0.05);
  color: #ffffff;
}

/* Archive */
.archive-box {
  background: #000000;
  border: 1px solid var(--border);
  padding: 16px;
  border-radius: 4px;
  text-align: center;
}

.preview-img {
  max-width: 100%;
  height: auto;
  border: 1px solid #222222;
}

/* Contact */
.contact-box {
  background: var(--card-bg);
  border: 1px solid var(--border);
  padding: 22px;
  border-radius: 4px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}

.contact-box h3 { margin: 0 0 6px; color: #ffffff; }
.contact-box p { margin: 0; color: var(--text-muted); font-size: 0.9rem; max-width: 50ch; }
.contact-links { display: flex; gap: 10px; }

.btn {
  display: inline-block;
  padding: 8px 16px;
  border-radius: 4px;
  font-size: 0.88rem;
  font-weight: 600;
  text-decoration: none;
}

.btn-primary { background: var(--azure); color: #ffffff; }
.btn-primary:hover { background: #0369a1; }
.btn-ghost { border: 1px solid var(--border); color: #ffffff; }
.btn-ghost:hover { background: rgba(56, 189, 248, 0.1); }

/* Footer */
.site-footer {
  background: #05070a;
  border-top: 1px solid var(--border);
  padding: 14px 24px;
  font-size: 0.78rem;
  color: var(--text-muted);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.site-footer a { color: var(--cyan); }

@media (max-width: 768px) {
  .topic-grid { grid-template-columns: 1fr; }
  .top-nav { flex-direction: column; }
  .nav-link { border-right: none; border-bottom: 1px solid rgba(255, 255, 255, 0.05); }
}