@keyframes _si{from{opacity:0}to{opacity:1}}

.legacy-content .qa-answer {
  background: linear-gradient(135deg, rgba(8,145,178,0.06), rgba(0,102,255,0.05));
  border: 1.5px solid rgba(8,145,178,0.3);
  border-radius: var(--radius); padding: 22px 26px; margin: 4px 0 8px;
}.legacy-content .qa-answer .qa-tag { font-size: 11px; font-weight: 800; letter-spacing: 1px; color: #0891b2; margin-bottom: 8px; }.legacy-content .qa-answer p { font-size: 16.5px; font-weight: 700; color: var(--text); line-height: 1.85; }.legacy-content .qa-answer p b { color: #0891b2; }.legacy-content .ladder { display: flex; flex-direction: column-reverse; gap: 10px; }.legacy-content .ladder-rung {
  background: var(--card); border: 1.5px solid var(--border);
  border-radius: var(--radius); box-shadow: var(--shadow-card);
  overflow: hidden; cursor: pointer; transition: border-color 0.2s;
}.legacy-content .ladder-rung:hover { border-color: rgba(0,102,255,0.35); }.legacy-content .rung-head { display: flex; align-items: center; gap: 12px; padding: 15px 18px; }.legacy-content .rung-lv {
  flex-shrink: 0; width: 40px; height: 40px; border-radius: 10px;
  display: flex; align-items: center; justify-content: center;
  font-size: 14px; font-weight: 800; color: #fff;
}.legacy-content .rung-l1 .rung-lv { background: #16a34a; }.legacy-content .rung-l2 .rung-lv { background: #0891b2; }.legacy-content .rung-l3 .rung-lv { background: #d97706; }.legacy-content .rung-l4 .rung-lv { background: #7c3aed; }.legacy-content .rung-title { flex: 1; }.legacy-content .rung-title h4 { font-size: 15px; font-weight: 800; color: var(--text); }.legacy-content .rung-title .rung-hint { font-size: 12px; color: var(--sub); margin-top: 2px; }.legacy-content .rung-arrow { font-size: 13px; color: var(--sub); transition: transform 0.25s; flex-shrink: 0; }.legacy-content .ladder-rung.open .rung-arrow { transform: rotate(90deg); }.legacy-content .rung-body {
  max-height: 0; overflow: hidden; transition: max-height 0.35s ease;
  border-top: 0 solid var(--border);
}.legacy-content .ladder-rung.open .rung-body { max-height: 400px; border-top: 1px solid var(--border); }.legacy-content .rung-facts { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; padding: 14px 18px; }.legacy-content .rung-fact { background: rgba(0,0,0,0.025); border-radius: var(--radius-sm); padding: 10px 13px; }.legacy-content .rung-fact .rf-k { font-size: 11px; font-weight: 800; letter-spacing: 0.5px; color: var(--sub); margin-bottom: 3px; }.legacy-content .rung-fact .rf-v { font-size: 13px; font-weight: 700; color: var(--text); line-height: 1.6; }.legacy-content .rung-desc { padding: 0 18px 15px; font-size: 13px; color: var(--sub); line-height: 1.8; }.legacy-content .rung-desc b { color: var(--accent); }.legacy-content .quiz-item {
  background: var(--card); border: 1.5px solid var(--border);
  border-radius: var(--radius); box-shadow: var(--shadow-card);
  padding: 18px 20px; margin-bottom: 14px;
}.legacy-content .quiz-item .qz-say {
  font-size: 15px; font-weight: 700; color: var(--text); line-height: 1.8;
  margin-bottom: 12px;
}.legacy-content .qz-opts { display: flex; flex-wrap: wrap; gap: 8px; }.legacy-content .qz-opt {
  border: 1.5px solid var(--border); background: var(--card);
  border-radius: 999px; padding: 7px 15px;
  font-size: 12.5px; font-weight: 800; color: var(--sub);
  cursor: pointer; font-family: inherit; transition: all 0.15s;
}.legacy-content .qz-opt:hover { border-color: rgba(0,102,255,0.4); color: var(--accent); }.legacy-content .qz-opt:disabled { cursor: default; }.legacy-content .qz-opt.hit { border-color: var(--success); background: rgba(22,163,74,0.08); color: var(--success); }.legacy-content .qz-opt.miss { border-color: var(--danger); background: rgba(220,38,38,0.06); color: var(--danger); }.legacy-content .qz-opt.dim { opacity: 0.45; }.legacy-content .qz-reveal {
  display: none; margin-top: 12px; padding: 12px 15px;
  border-radius: var(--radius-sm); background: rgba(8,145,178,0.05);
  border: 1px solid rgba(8,145,178,0.2);
  font-size: 13px; color: var(--text); line-height: 1.8;
}.legacy-content .qz-reveal.show { display: block; }.legacy-content .qz-reveal b { color: #0891b2; }.legacy-content .quiz-score {
  display: none; margin-top: 4px; padding: 14px 18px;
  border-radius: var(--radius); text-align: center;
  background: rgba(22,163,74,0.06); border: 1.5px solid rgba(22,163,74,0.25);
  font-size: 14px; font-weight: 800; color: var(--success);
}.legacy-content .quiz-score.show { display: block; }.legacy-content .pt-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }.legacy-content .pt-card {
  background: var(--card); border: 1.5px solid var(--border);
  border-radius: var(--radius); padding: 18px 20px; box-shadow: var(--shadow-card);
}.legacy-content .pt-card .pt-icon { font-size: 26px; margin-bottom: 8px; }.legacy-content .pt-card h4 { font-size: 14.5px; font-weight: 800; color: var(--text); margin-bottom: 5px; }.legacy-content .pt-card p { font-size: 12.5px; color: var(--sub); line-height: 1.8; }.legacy-content .pt-card p b { color: var(--text); }.legacy-content .takeaway-box {
  background: linear-gradient(135deg, #eff6ff, #eef2ff);
  border: 1.5px solid #bfdbfe; border-radius: var(--radius);
  padding: 24px 28px; margin-top: 36px;
}.legacy-content .takeaway-box h3 { font-size: 17px; font-weight: 800; color: #1e40af; margin-bottom: 10px; }.legacy-content .takeaway-box ul { list-style: none; padding: 0; margin: 0; }.legacy-content .takeaway-box li {
  font-size: 14.5px; color: #1e3a5f; line-height: 1.8;
  padding: 4px 0 4px 22px; position: relative;
}.legacy-content .takeaway-box li::before {
  content: ''; position: absolute; left: 0; top: 13px;
  width: 8px; height: 8px; border-radius: 50%; background: #3b82f6;
}@media (max-width: 768px){.legacy-content .pt-grid { grid-template-columns: 1fr; }.legacy-content .qa-answer p { font-size: 15px; }.legacy-content .rung-facts { grid-template-columns: 1fr; }.legacy-content .qz-opts { gap: 6px; }.legacy-content .qz-opt { padding: 8px 13px; }}