/* 36 substantive bilingual teaching chapters: concept → why → model → example → build → audit */
#learn .teach-intro{padding:12px 16px;background:#e9f6f3;border-radius:11px;border:1px solid #c9e5dd;margin:0 0 15px}
#learn .teach-intro span{display:block;font-size:11px;font-weight:850;letter-spacing:.09em;color:#0b786c}
#learn .teach-intro p{margin:5px 0 0;color:#3b6670;font-size:13px;line-height:1.6}
#learn .teach-knowledge{display:grid;gap:12px}
#learn .teach-card{padding:18px 20px;border:1px solid #d6e6e7;background:#fff;border-radius:13px;box-shadow:0 2px 10px rgba(18,66,75,.025)}
#learn .teach-card-title{display:flex;align-items:center;gap:12px}
#learn .teach-card-title>span{display:flex;align-items:center;justify-content:center;width:36px;height:36px;border-radius:10px;background:#e4f5f0;color:#0c8573;font-size:12px;font-weight:850;flex:none}
#learn .teach-card-title strong{display:block;font-size:15px;color:#173f51}
#learn .teach-card-title small{display:block;font-size:11px;color:#68838d;margin-top:2px}
#learn .teach-pair{margin-top:12px}
#learn .teach-pair p{font-size:14px;color:#304f5f;line-height:1.8;margin:0}
#learn .teach-pair p[lang="en"]{margin-top:9px;padding-top:9px;border-top:1px dashed #d9e7e9;color:#647c89;font-size:12.5px;line-height:1.65}
#learn .teach-boundary{background:#fff8e9;border:1px solid #f0dfb8;padding:12px 15px;border-radius:10px;color:#745b33;font-size:12px;line-height:1.6}
#learn .teach-boundary b{color:#7e5721}
#learn .teach-boundary p{margin:5px 0 0;font-size:12px;color:#745b33}
#learn .teach-example h4{color:#1a4958;font-size:16px;margin:0 0 8px}
#learn .teach-example .teach-lead{font-size:12px;color:#647c86;margin:0 0 15px;line-height:1.7}
#learn .teach-example .teach-lead span{color:#3e6671}
#learn .teach-example>.teach-pair{background:#f4f9fb;border:1px solid #dce9ed;padding:15px 18px;border-radius:11px}
#learn .teach-flow-label{margin:20px 0 9px;color:#315f6d;font-weight:800;font-size:12px}
#learn .teach-flow{display:flex;align-items:center;flex-wrap:wrap;gap:7px;margin:0 0 16px}
#learn .teach-flow span{border:1px solid #c7e3dd;background:#e9f8f3;color:#146b63;font-size:11px;font-weight:720;padding:9px 11px;border-radius:8px;line-height:1.5}
#learn .teach-flow i{color:#71a6a2;font-style:normal;font-weight:800}
#learn .teach-code{background:#152c3b;border-radius:12px;border:1px solid #304b5d;overflow:hidden;margin-top:17px}
#learn .teach-code summary{color:#d3f2ed;cursor:pointer;font-weight:780;padding:14px 17px;font-size:12px}
#learn .teach-code[open] summary{border-bottom:1px solid #355362}
#learn .teach-code p{font-size:12px;color:#b2c9d0;padding:0 17px}
#learn .teach-code pre{margin:0;padding:14px 17px;white-space:pre-wrap;overflow-wrap:anywhere;overflow-x:auto;color:#d9f5e7;font:12px/1.7 ui-monospace,SFMono-Regular,Consolas,monospace}
#learn .teach-copy{margin:0 17px 15px;background:#274a59;color:#e0fff4;border:1px solid #49717b;border-radius:7px;padding:8px 11px;font-size:12px;font-weight:700;cursor:pointer}
#learn .teach-copy:hover{background:#356a70}
#learn .teach-guide{border:1px solid #d1e7e4;border-radius:14px;overflow:hidden;background:#fff}
#learn .teach-guide-head{padding:15px 18px;background:#e9f6f3;display:flex;justify-content:space-between;gap:10px;flex-wrap:wrap;align-items:center}
#learn .teach-guide-head strong{font-size:12px;color:#117769;letter-spacing:.04em}
#learn .teach-guide-head small{font-size:12px;color:#4c7981}
#learn .teach-task-row{display:grid;grid-template-columns:190px 1fr;gap:15px;padding:15px 18px;border-top:1px solid #e7eff0;align-items:start}
#learn .teach-task-time{font-size:12px;color:#1a776e;font-weight:850}
#learn .teach-task-row p{margin:0;color:#395b68;font-size:13px;line-height:1.65}
#learn .teach-specific{padding:15px 18px;background:#f6fafb;border-top:1px solid #e0eced}
#learn .teach-specific strong{display:block;color:#28576b;font-size:12px;margin-bottom:6px}
#learn .teach-specific p{font-size:13px;color:#365e6b;margin:5px 0;line-height:1.7}
#learn .teach-specific p[lang="en"]{font-size:12px;color:#748b95}
#learn .teach-specific .teach-pair{margin-top:5px}
#learn .teach-audit{background:#fff9ed}
#learn .teach-evidence{padding:13px 18px;background:#e9f7f0;border-top:1px solid #d3e8df;font-size:12px;line-height:1.6;color:#2b655c}
#learn .teach-evidence span{display:block}
@media(max-width:680px){#learn .teach-card{padding:14px}#learn .teach-task-row{grid-template-columns:1fr;gap:5px;padding:12px 14px}#learn .teach-guide-head{padding:13px}#learn .teach-specific{padding:13px}#learn .teach-flow span{font-size:10px;padding:7px}#learn .teach-pair p{font-size:13px}}