:root {
  --bg: #ffffff;
  --text: #003c47;
  --muted: #64748b;
  --accent: #003c47;
  --radius: 14px;
}

.containertd {
  max-width: 1250px;
  margin: 0 auto;
  background: var(--bg);
  padding: 28px;
  border-radius: var(--radius);
  box-shadow: 0 10px 35px rgba(15, 23, 42, 0.08);
  margin-top: 30px;
}
.headerTD {
  display: flex;
  gap: 16px;
  align-items: center;
  margin-bottom: 18px;
}
.logo {
  width: 58px;
  height: 58px;
  border-radius: 12px;
  /* background: linear-gradient(135deg, var(--accent), #6fb1ff); */
  color: #fff;
  font-weight: 800;
  font-size: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.title {
  margin: 0;
  font-size: 24px;
  font-weight: 700;
}
.lead {
  margin: 2px 0 0;
  color: #003c47;
  font-size: 15px;
  font-weight: 400;
}
.toc {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 22px 0;
}
.toc a {
  padding: 9px 14px;
  background: #e2e8f0;
  border-radius: 999px;
  text-decoration: none;
  font-size: 15px;
  font-weight: 600;
  color: var(--accent);
}
.main {
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
}
.card {
  background: #fff;
  border-radius: 12px;
  padding: 18px;
  border: 1px solid rgba(15, 98, 254, 0.08);
  line-height: 28px;
  font-size: 16px;
}
.cardtieude {
  margin-top: 0;
  font-size: 18px;
  color: var(--accent);
  font-weight: bold;
}
.small {
  color: var(--muted);
  font-size: 15px;
  margin-top: 10px;
}
ul,
ol {
  margin: 10px 0 0 22px;
}
@media (max-width: 720px) {
  body {
    padding: 14px;
  }
  .container {
    padding: 18px;
  }
  .title {
    font-size: 20px;
  }
  .toc a {
    font-size: 12px;
    padding: 7px 10px;
  }
}