.page {
  max-width: 1160px;
  margin: 0 auto;
  padding: 2rem 1rem 4rem;
}

.layout {
  display: grid;
  gap: 2rem;
  align-items: start;
}

@media (min-width: 960px) {
  .layout {
    grid-template-columns: minmax(0, 1fr) 280px;
  }
}

.toc {
  position: sticky;
  top: calc(var(--navbar-height, 64px) + 1rem);
  align-self: start;
  max-height: calc(100vh - 2rem);
  overflow: auto;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 1.5rem;
  box-shadow: 0 18px 40px rgba(15, 23, 42, 0.08);
}

.toc h2 {
  margin: 0 0 1rem;
  font-size: 0.95rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.toc ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.toc li + li {
  margin-top: 0.9rem;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 2rem;
  box-shadow: 0 20px 40px rgba(15, 23, 42, 0.06);
}

.card h2,
.card h3 {
  color: var(--text);
}

.card h2 {
  margin-top: 0;
}

.card p,
.card li {
  line-height: 1.75;
}

.card ul {
  padding-left: 1.4rem;
}

.card img {
  width: 100%;
  border-radius: 20px;
  margin-top: 1.5rem;
}

.highlight {
  border-left: 4px solid #2563eb;
  padding: 1rem 1rem 1rem 1rem;
  background: #eff6ff;
  border-radius: 16px;
  margin: 1.5rem 0;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 1rem;
  font-weight: 600;
  color: var(--primary);
}