:root {
  --bg: #050817;
  --bg-soft: #0a1228;
  --card: #0e1a35;
  --card-hover: #132144;
  --text: #f3f6ff;
  --muted: #a7b5d6;
  --line: #1e2d56;
  --accent: #5eead4;
  --accent-strong: #2dd4bf;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: radial-gradient(circle at 15% -20%, #16315f 0%, var(--bg) 40%),
    var(--bg);
  color: var(--text);
  line-height: 1.55;
}

a {
  color: var(--accent);
  text-decoration: none;
}

.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 1rem;
}

.row {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.wrap {
  flex-wrap: wrap;
}

.gap {
  gap: 0.75rem;
}

.site-header,
.site-footer {
  border-bottom: 1px solid var(--line);
  border-top: 1px solid var(--line);
  padding: 0.85rem 0;
  backdrop-filter: blur(4px);
}

.site-footer {
  margin-top: 3rem;
}

.brand {
  color: var(--text);
  font-weight: 700;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

.brand-notebook {
  width: 18px;
  height: 18px;
  display: block;
}

.nav {
  display: flex;
  gap: 1rem;
}

.hero {
  padding: 2.8rem 0 1.7rem;
  border-bottom: 1px solid var(--line);
}

.eyebrow {
  font-weight: 700;
  color: var(--accent);
  margin: 0;
}

.micro,
.muted {
  color: var(--muted);
  margin: 0.4rem 0;
}

#hero-title {
  margin: 0.35rem 0 0;
  font-size: clamp(1.8rem, 4vw, 3rem);
  letter-spacing: -0.02em;
}

#hero-tagline {
  margin: 0.7rem 0 0;
  max-width: 70ch;
  color: var(--muted);
}

.stats {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.75rem;
  margin-top: 1rem;
}

.stat {
  background: linear-gradient(180deg, #122346 0%, var(--card) 100%);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 0.9rem;
}

.stat strong {
  display: block;
  font-size: 1.2rem;
}

.filters {
  margin: 1.25rem 0 1rem;
}

.pill {
  border: 1px solid var(--line);
  background: #0b1630;
  color: var(--text);
  padding: 0.5rem 0.9rem;
  border-radius: 999px;
  cursor: pointer;
  transition: border-color 0.2s ease, color 0.2s ease, transform 0.15s ease;
}

.pill:hover {
  border-color: var(--accent-strong);
  transform: translateY(-1px);
}

.pill.active {
  border-color: var(--accent);
  color: var(--accent);
  background: rgba(45, 212, 191, 0.08);
}

.pill-count {
  color: var(--muted);
  margin-left: 0.25rem;
}

.cards {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.9rem;
}

.cards.list {
  grid-template-columns: 1fr;
}

.card {
  display: block;
  background: linear-gradient(180deg, #13264d 0%, var(--card) 100%);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 1rem;
  color: var(--text);
  transition: transform 0.18s ease, border-color 0.2s ease, background 0.2s ease;
}

.card:hover {
  transform: translateY(-2px);
  border-color: var(--accent-strong);
  background: var(--card-hover);
}

.card h3 {
  margin: 0.2rem 0 0.5rem;
}

.card small {
  color: var(--muted);
}

.methodology {
  margin-top: 2.2rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
}

.method-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.85rem;
}

.method-item {
  border: 1px solid var(--line);
  background: linear-gradient(180deg, #13264d 0%, var(--card) 100%);
  border-radius: 10px;
  padding: 0.85rem;
}

.method-item h3 {
  margin: 0.25rem 0 0.35rem;
}

.article-shell {
  padding-top: 1.5rem;
}

.back-link {
  color: var(--muted);
  display: inline-block;
  margin-bottom: 0.8rem;
}

.lead {
  color: var(--muted);
  margin-top: -0.35rem;
  margin-bottom: 1.2rem;
  border-bottom: 1px solid var(--line);
  padding-bottom: 0.8rem;
}

.prose h1,
.prose h2,
.prose h3 {
  margin-top: 1.3rem;
  margin-bottom: 0.5rem;
}

.prose p {
  margin: 0.6rem 0;
}

.prose ul {
  margin: 0.2rem 0 0.8rem 1.25rem;
}

.prose li {
  margin-bottom: 0.3rem;
}

.prompt-block {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: linear-gradient(180deg, #0d1f42 0%, #0a1730 100%);
  padding: 0.9rem;
  margin: 1rem 0;
}

.prompt-block h3 {
  margin: 0 0 0.55rem;
}

.prompt-block details {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--bg-soft);
  margin-bottom: 0.65rem;
}

.prompt-block summary {
  cursor: pointer;
  color: var(--accent);
  list-style: none;
  padding: 0.55rem 0.65rem;
  font-weight: 600;
}

.prompt-block summary::-webkit-details-marker {
  display: none;
}

.prompt-block pre {
  margin: 0;
  white-space: pre-wrap;
  font-family: "Consolas", "Courier New", monospace;
  font-size: 0.9rem;
  line-height: 1.45;
  color: #dbeafe;
  border-top: 1px solid var(--line);
  padding: 0.75rem;
}

.copy-prompt {
  border: 1px solid var(--accent-strong);
  background: rgba(45, 212, 191, 0.08);
  color: var(--accent);
  border-radius: 8px;
  padding: 0.35rem 0.65rem;
  cursor: pointer;
}

.prompt-why {
  margin: 0.65rem 0 0;
  color: var(--muted);
}

@media (max-width: 900px) {
  .stats,
  .cards,
  .method-grid {
    grid-template-columns: 1fr;
  }

  .row {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.65rem;
  }
}