:root {
  --bg: #0f172a;
  --bg-soft: #111827;
  --surface: #1f2937;
  --text: #e5e7eb;
  --muted: #94a3b8;
  --brand: #38bdf8;
  --brand-strong: #0ea5e9;
  --accent: #f59e0b;
  --max: 1080px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: linear-gradient(180deg, #020617 0%, #0f172a 30%, #111827 100%);
  color: var(--text);
  line-height: 1.6;
}

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

a:hover {
  text-decoration: underline;
}

.container {
  width: min(94%, var(--max));
  margin: 0 auto;
}

header {
  position: sticky;
  top: 0;
  backdrop-filter: blur(10px);
  background: rgba(2, 6, 23, 0.82);
  border-bottom: 1px solid rgba(148, 163, 184, 0.2);
  z-index: 10;
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 14px 0;
}

.brand {
  font-weight: 700;
  font-size: 1rem;
  letter-spacing: 0.02em;
  color: #f8fafc;
}

.menu {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 0.92rem;
}

.menu a {
  color: #cbd5e1;
  padding: 6px 8px;
  border-radius: 8px;
}

.menu a:hover,
.menu a.active {
  background: rgba(56, 189, 248, 0.15);
  color: #fff;
  text-decoration: none;
}

.hero {
  padding: 80px 0 44px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.25fr 1fr;
  gap: 26px;
}

.panel {
  background: linear-gradient(165deg, rgba(56, 189, 248, 0.1), rgba(15, 23, 42, 0.6));
  border: 1px solid rgba(148, 163, 184, 0.2);
  border-radius: 18px;
  padding: 22px;
}

h1, h2, h3 {
  line-height: 1.2;
  margin: 0 0 14px;
}

h1 { font-size: clamp(1.8rem, 4vw, 3rem); }
h2 { font-size: clamp(1.4rem, 2.8vw, 2rem); margin-top: 12px; }
h3 { font-size: 1.1rem; }

p {
  margin: 0 0 14px;
  color: #dbe4ef;
}

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

.cta-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 18px;
}

.btn {
  display: inline-block;
  padding: 10px 14px;
  border-radius: 10px;
  border: 1px solid rgba(148, 163, 184, 0.25);
  color: #fff;
  background: transparent;
  font-weight: 600;
}

.btn.primary {
  background: linear-gradient(180deg, var(--brand), var(--brand-strong));
  border-color: transparent;
  color: #082f49;
}

.btn.primary:hover {
  text-decoration: none;
  filter: brightness(1.06);
}

.section {
  padding: 24px 0 40px;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.card {
  background: rgba(15, 23, 42, 0.72);
  border: 1px solid rgba(148, 163, 184, 0.2);
  border-radius: 14px;
  padding: 16px;
}

ul {
  padding-left: 20px;
  margin: 0;
}

li {
  margin-bottom: 8px;
}

blockquote {
  border-left: 3px solid var(--brand);
  margin: 20px 0;
  padding: 14px 18px;
  background: rgba(56, 189, 248, 0.06);
  border-radius: 0 10px 10px 0;
  font-style: italic;
  color: var(--text);
}

blockquote cite {
  display: block;
  margin-top: 10px;
  font-style: normal;
  font-size: 0.88rem;
  color: var(--muted);
}

.breadcrumb {
  font-size: 0.85rem;
  color: var(--muted);
  margin-bottom: 10px;
}

.breadcrumb a {
  color: var(--muted);
}

.breadcrumb a:hover {
  color: var(--brand);
}

.drill-box {
  background: rgba(245, 158, 11, 0.08);
  border: 1px solid rgba(245, 158, 11, 0.25);
  border-radius: 14px;
  padding: 18px;
  margin: 20px 0;
}

.drill-box h3 {
  color: var(--accent);
  margin-bottom: 8px;
}

.scenario {
  background: var(--surface);
  border-radius: 12px;
  padding: 16px;
  margin: 16px 0;
}

.scenario h3 {
  font-size: 1rem;
  margin-bottom: 6px;
}

.internal-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 20px 0;
}

.internal-links a {
  padding: 6px 12px;
  background: rgba(56, 189, 248, 0.1);
  border: 1px solid rgba(56, 189, 248, 0.2);
  border-radius: 8px;
  font-size: 0.88rem;
}

.img-slot {
  background: var(--surface);
  border: 1px dashed rgba(148, 163, 184, 0.3);
  border-radius: 14px;
  min-height: 180px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--muted);
  font-size: 0.85rem;
  margin: 16px 0;
}

.page-content {
  max-width: 780px;
}

.page-content h2 {
  margin-top: 32px;
}

.page-content p + p {
  margin-top: 0;
}

footer {
  margin-top: 30px;
  padding: 22px 0 30px;
  border-top: 1px solid rgba(148, 163, 184, 0.2);
  color: var(--muted);
  font-size: 0.9rem;
}

@media (max-width: 920px) {
  .hero-grid,
  .grid-3 {
    grid-template-columns: 1fr;
  }

  .hero {
    padding-top: 56px;
  }
}