html,
body {
  margin: 0;
  min-height: 100%;
  background:
    radial-gradient(circle at top right, rgba(232, 97, 0, 0.12), transparent 24%),
    linear-gradient(180deg, #faf6ef 0%, #f4f0e8 100%);
}

body {
  font-family: "Atkinson Hyperlegible", "Segoe UI", sans-serif;
}

.overview-page {
  --bg: #f4f0e8;
  --panel: rgba(255, 255, 255, 0.88);
  --panel-border: rgba(11, 35, 65, 0.12);
  --text: #18263b;
  --muted: #5d6978;
  --accent: #e86100;
  --accent-dark: #b74900;
  --shadow: 0 20px 40px rgba(11, 35, 65, 0.12);
  --foundation: #d9edf7;
  --structure: #efe4ff;
  --geometry: #dcefd2;
  --spectral: #ffe7c7;
  --applications: #fde2e4;
  color: var(--text);
  min-height: 100vh;
  width: 100%;
  margin: 0;
  padding: 0;
}

.overview-page * {
  box-sizing: border-box;
}

.overview-page .overview-shell {
  display: grid;
  grid-template-columns: 320px minmax(0, 1fr);
  min-height: 100vh;
  height: 100vh;
  width: 100%;
  overflow: hidden;
  border: 1px solid rgba(11, 35, 65, 0.08);
  border-radius: 0;
  background:
    radial-gradient(circle at top right, rgba(232, 97, 0, 0.12), transparent 24%),
    linear-gradient(180deg, #faf6ef 0%, var(--bg) 100%);
  box-shadow: var(--shadow);
}

.overview-page .overview-sidebar,
.overview-page .overview-main-panel,
.overview-page .overview-graph-stage,
.overview-page .overview-details-card {
  min-height: 0;
}

.overview-page .overview-sidebar {
  padding: 28px 24px;
  background: rgba(255, 255, 255, 0.75);
  border-right: 1px solid var(--panel-border);
  backdrop-filter: blur(10px);
  overflow-y: auto;
}

.overview-page .overview-sidebar-header h1,
.overview-page .overview-main-header h2,
.overview-page .overview-details-card h3 {
  margin: 0;
  font-family: Georgia, "Times New Roman", serif;
  letter-spacing: 0.01em;
}

.overview-page .overview-sidebar-header p,
.overview-page .overview-main-header p,
.overview-page .overview-details-card p,
.overview-page .overview-search-box span {
  color: var(--muted);
  line-height: 1.55;
}

.overview-page .back-link {
  display: inline-block;
  margin-bottom: 16px;
  color: var(--accent-dark);
  font-size: 0.95rem;
  text-decoration: none;
}

.overview-page .back-link:hover,
.overview-page .back-link:focus {
  text-decoration: underline;
}

.overview-page .overview-search-box {
  display: grid;
  gap: 8px;
  margin-top: 24px;
}

.overview-page .overview-search-box input {
  width: 100%;
  padding: 11px 13px;
  border: 1px solid rgba(11, 35, 65, 0.18);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.95);
  color: var(--text);
  font: inherit;
}

.overview-page .overview-controls {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin: 18px 0 22px;
}

.overview-page .overview-controls button,
.overview-page .overview-toc-link,
.overview-page .overview-related-button,
.overview-page .overview-resource-link {
  font: inherit;
  border-radius: 12px;
  border: 1px solid transparent;
  transition:
    transform 0.15s ease,
    box-shadow 0.15s ease,
    border-color 0.15s ease,
    background-color 0.15s ease;
}

.overview-page .overview-controls button {
  padding: 10px 12px;
  background: #fff;
  border-color: rgba(11, 35, 65, 0.12);
  color: var(--text);
  cursor: pointer;
}

.overview-page .overview-controls button:hover,
.overview-page .overview-controls button:focus,
.overview-page .overview-toc-link:hover,
.overview-page .overview-toc-link:focus,
.overview-page .overview-related-button:hover,
.overview-page .overview-related-button:focus,
.overview-page .overview-resource-link:hover,
.overview-page .overview-resource-link:focus {
  transform: translateY(-1px);
  box-shadow: 0 8px 20px rgba(11, 35, 65, 0.1);
}

.overview-page .overview-toc {
  display: grid;
  gap: 12px;
  padding-bottom: 40px;
}

.overview-page .overview-toc-group {
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: 16px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.overview-page .overview-toc-group summary {
  padding: 14px 16px;
  font-weight: 700;
  cursor: pointer;
  list-style: none;
}

.overview-page .overview-toc-group summary::-webkit-details-marker {
  display: none;
}

.overview-page .overview-toc-items {
  display: grid;
  gap: 8px;
  padding: 0 12px 14px;
}

.overview-page .overview-toc-link {
  width: 100%;
  text-align: left;
  padding: 11px 12px;
  background: #fff;
  border-color: rgba(11, 35, 65, 0.08);
  cursor: pointer;
}

.overview-page .overview-toc-link small,
.overview-page .section-note,
.overview-page .meta-row {
  display: block;
  margin-top: 3px;
  color: var(--muted);
}

.overview-page .overview-toc-link.is-active {
  border-color: rgba(232, 97, 0, 0.35);
  background: rgba(232, 97, 0, 0.08);
}

.overview-page .overview-main-panel {
  display: flex;
  flex-direction: column;
  gap: 18px;
  padding: 28px;
  overflow: hidden;
}

.overview-page .overview-main-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 18px;
}

.overview-page .overview-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.overview-page .overview-legend li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--muted);
  font-size: 0.95rem;
}

.overview-page .overview-swatch {
  width: 14px;
  height: 14px;
  border-radius: 4px;
  border: 1px solid rgba(11, 35, 65, 0.12);
}

.overview-page .foundation {
  background: var(--foundation);
}

.overview-page .structure {
  background: var(--structure);
}

.overview-page .geometry {
  background: var(--geometry);
}

.overview-page .spectral {
  background: var(--spectral);
}

.overview-page .applications {
  background: var(--applications);
}

.overview-page .overview-graph-stage {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 330px;
  gap: 18px;
  flex: 1;
}

.overview-page .overview-network {
  height: 100%;
  min-height: 0;
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid var(--panel-border);
  border-radius: 24px;
  box-shadow: var(--shadow);
}

.overview-page .overview-details-card {
  padding: 18px 18px 16px;
  overflow-y: auto;
  background: rgba(255, 255, 255, 0.94);
  border: 1px solid var(--panel-border);
  border-radius: 18px;
  box-shadow: var(--shadow);
}

.overview-page .overview-details-kicker {
  margin: 0 0 6px;
  color: var(--accent-dark);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.overview-page .badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin: 10px 0 14px;
  padding: 4px 10px;
  border-radius: 999px;
  background: rgba(11, 35, 65, 0.08);
  color: var(--muted);
  font-size: 0.9rem;
}

.overview-page .overview-details-list,
.overview-page .overview-starter-list {
  margin: 0;
  padding-left: 18px;
  line-height: 1.55;
}

.overview-page .overview-related-list,
.overview-page .overview-resource-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}

.overview-page .overview-related-button {
  padding: 8px 11px;
  background: rgba(232, 97, 0, 0.08);
  border-color: rgba(232, 97, 0, 0.12);
  color: var(--accent-dark);
  cursor: pointer;
}

.overview-page .overview-resource-link {
  display: inline-flex;
  align-items: center;
  padding: 8px 11px;
  background: rgba(11, 35, 65, 0.06);
  border-color: rgba(11, 35, 65, 0.1);
  color: var(--text);
  text-decoration: none;
}

.overview-page .empty-state {
  padding: 16px;
  border: 1px dashed rgba(11, 35, 65, 0.18);
  border-radius: 14px;
  color: var(--muted);
  background: rgba(255, 255, 255, 0.72);
}

.overview-hover-tooltip {
  position: fixed;
  z-index: 9999;
  max-width: 340px;
  padding: 10px 12px;
  border: 1px solid rgba(11, 35, 65, 0.14);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.96);
  color: #18263b;
  box-shadow: 0 14px 28px rgba(11, 35, 65, 0.18);
  pointer-events: none;
  line-height: 1.45;
  font-size: 0.95rem;
  opacity: 0;
  transform: translateY(4px);
  transition: opacity 0.12s ease, transform 0.12s ease;
}

.overview-hover-tooltip.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.overview-tooltip-title {
  font-family: Georgia, "Times New Roman", serif;
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.overview-tooltip-meta {
  color: #5d6978;
  font-size: 0.88rem;
  margin-bottom: 6px;
}

.overview-tooltip-body {
  line-height: 1.45;
}

@media (max-width: 1200px) {
  .overview-page .overview-shell {
    grid-template-columns: 290px minmax(0, 1fr);
  }

  .overview-page .overview-graph-stage {
    grid-template-columns: minmax(0, 1fr) 300px;
  }
}

@media (max-width: 1024px) {
  .overview-page .overview-shell {
    display: block;
    height: auto !important;
    min-height: 100vh;
    overflow: visible;
  }

  .overview-page .overview-sidebar,
  .overview-page .overview-main-panel,
  .overview-page .overview-details-card {
    overflow: visible;
  }

  .overview-page .overview-sidebar {
    border-right: 0;
    border-bottom: 1px solid var(--panel-border);
  }

  .overview-page .overview-graph-stage {
    grid-template-columns: 1fr;
  }

  .overview-page .overview-network {
    min-height: 600px;
  }
}

@media (max-width: 720px) {

  .overview-page .overview-sidebar,
  .overview-page .overview-main-panel {
    padding: 18px;
  }

  .overview-page .overview-main-header {
    flex-direction: column;
  }

  .overview-page .overview-controls {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .overview-page .overview-network {
    min-height: 460px;
  }
}