:root {
  --bt-ink: #1d2226;
  --bt-paper: #f7f5f0;
  --bt-rule: #d9d2c3;
  --bt-pin: #b8402a;
  --bt-quiet: #5f6a70;
  --bt-measure: 44rem;
}
body.bangtin {
  background: var(--bt-paper);
  color: var(--bt-ink);
  font-family: "Segoe UI", Roboto, "Noto Sans", Arial, sans-serif;
  line-height: 1.65;
  margin: 0;
}
.bt-khung {
  max-width: var(--bt-measure);
  margin: 0 auto;
  padding: 2rem 1.25rem 3.5rem;
}
.bt-lede {
  font-size: 1.08rem;
  border-left: 4px solid var(--bt-pin);
  padding: 0.2rem 0 0.2rem 0.9rem;
  margin: 0 0 1.6rem;
}
.bt-tom {
  background: #fff;
  border: 1px solid var(--bt-rule);
  border-top: 4px solid var(--bt-pin);
  padding: 0.9rem 1.1rem 1rem;
  margin: 1.6rem 0;
}
.bt-tom ul { margin: 0; padding-left: 1.1rem; }
.bt-fact { margin: 0 0 0.55rem; }
.bt-phan { margin: 2rem 0 0; }
.bt-phan ul { padding-left: 1.2rem; }
.bt-gioihan {
  border: 1px dashed var(--bt-rule);
  padding: 0.6rem 1rem 0.9rem;
}
.bt-tincay { border-left: 3px solid var(--bt-quiet); padding-left: 0.9rem; }
.bt-hopthu {
  margin: 1.1rem 0 0;
  font-weight: 600;
  overflow-wrap: anywhere;
}
.bt-hoidap h3 { font-size: 1.02rem; margin: 1.3rem 0 0.35rem; }
.bt-muc {
  list-style: none;
  padding: 0;
  margin: 1.2rem 0;
}
.bt-muc li {
  border-bottom: 1px solid var(--bt-rule);
  padding: 0.6rem 0;
}
.bt-muc span {
  display: block;
  color: var(--bt-quiet);
  font-size: 0.92rem;
}
.bt-dau { background: var(--bt-ink); }
.bt-dan ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin: 0;
  padding: 0.9rem 1.25rem;
}
.bt-dan a { color: #fff; text-decoration: none; }
.bt-chan {
  max-width: var(--bt-measure);
  margin: 0 auto;
  padding: 1.5rem 1.25rem 2.5rem;
  color: var(--bt-quiet);
  font-size: 0.9rem;
}
@media (max-width: 640px) {
  .bt-khung { padding: 1.4rem 1rem 2.5rem; }
  .bt-tom { padding: 0.8rem 0.9rem; }
}