:root {
  --bg: #f7f9fb;
  --card: #ffffff;
  --accent: #0b5ed7;
  --muted: #6b7280;
  --danger: #d9534f;
}
html,
body {
  height: 100%;
  margin: 0;
  background: var(--bg);
  color: #0f172a;
}
.wrap {
  max-width: 1020px;
  margin: 36px auto;
  padding: 28px;
  margin-top: 6em;
}
header {
  display: flex;
  align-items: center;
  gap: 16px;
}
.logo {
  width: 64px;
  height: 64px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--accent), #6cf);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 800;
  font-size: 20px;
}
h1 {
  margin: 0;
  font-size: 22px;
}
.meta {
  color: var(--muted);
  margin-top: 6px;
}
nav.toc {
  margin: 22px 0;
  padding: 18px;
  border-radius: 12px;
  background: linear-gradient(180deg, rgba(11, 94, 215, 0.06), transparent);
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}
nav.toc a {
  color: var(--accent);
  text-decoration: none;
  padding: 6px 10px;
  border-radius: 8px;
  background: rgba(11, 94, 215, 0.04);
  font-size: 14px;
}
article.card {
  background: var(--card);
  border-radius: 14px;
  padding: 24px;
  box-shadow: 0 6px 18px rgba(12, 18, 33, 0.06);
}
section {
  margin-bottom: 22px;
}
section h2 {
  font-size: 18px;
  margin: 0 0 8px;
}
p {
  line-height: 1.55;
  color: #12263b;
  margin: 8px 0;
}
ul {
  margin: 8px 0 8px 20px;
}
.note {
  background: #fff8e6;
  border-left: 4px solid #ffd66b;
  padding: 12px;
  border-radius: 8px;
  color: #4a3b00;
}

.danger {
  color: var(--danger);
  font-weight: 600;
}
@media (max-width: 640px) {
  .wrap {
    padding: 18px;
  }
  .logo {
    width: 52px;
    height: 52px;
  }
}