/* R19: only learning navigation; existing checkpoints and student files are unchanged. */
.basic-path{display:grid;gap:5px;margin:0 12px 10px;padding:8px;background:#f7faff;border:1px solid #dfeaf7;border-radius:11px}
.basic-path>a,.basic-path-current{display:block;padding:8px 10px;font-size:10px;line-height:1.5;color:#5e7794;text-decoration:none;border-radius:7px}
.basic-path-current{background:#e6f0ff;color:#1e5b99;font-weight:850}
.basic-path>a:hover{background:#e7f4ff;color:#195a95}
.basic-nav-tools{margin:0 12px 10px;padding:10px 11px;border:1px solid #d9e6f1;background:#f5f9ff;border-radius:11px;display:grid;gap:7px}
.basic-nav-tools>strong{font-size:12px;color:#1b456c}
.basic-nav-tools>button{border:1px solid #b4dbce;border-radius:7px;background:#e8f8f0;font-size:11px;font-weight:850;color:#137565;padding:9px 10px;text-align:left;line-height:1.5}
.basic-nav-tools>span{font-size:10px;color:#627f9b;line-height:1.6;overflow-wrap:anywhere}
.side nav{padding:0 12px 14px}
.basic-chapter{border:1px solid #e0e8f3;border-radius:10px;overflow:hidden;margin-bottom:9px}
.basic-chapter-trigger{display:flex;align-items:center;gap:8px;width:100%;padding:12px 8px;background:#f7faff;border:0;text-align:left;color:#23476a}
.basic-chapter-trigger:hover{background:#eaf4ff}
.basic-chapter-trigger:focus-visible{outline:3px solid #71adeb;outline-offset:-3px}
.basic-chapter-title{flex:1;min-width:0}
.basic-chapter-title strong,.basic-chapter-title small{display:block;overflow-wrap:anywhere}
.basic-chapter-title strong{font-size:11px}.basic-chapter-title small{font-size:9px;line-height:1.5;font-weight:400;color:#6f839a;margin-top:4px}
.basic-chapter-count{font-weight:850;background:#e4f0fc;color:#416b93;border-radius:6px;padding:3px 5px;font-size:10px}
.basic-chapter-trigger>span:last-child{font-size:17px;color:#8ca4b7}
.basic-chapter-list{padding:4px 5px 7px}.basic-chapter-list[hidden]{display:none}
.basic-chapter .lesson-link{padding:10px 6px;font-size:11px;gap:6px;align-items:flex-start;min-width:0}
.basic-chapter .lesson-link .id{min-width:24px;line-height:1.65;font-size:10px}
.basic-chapter .lesson-name{flex:1;min-width:0;overflow-wrap:anywhere}
.basic-step-state{flex:none;color:#168473;font-size:10px;max-width:35px;text-align:right}
.basic-chapter .lesson-link[aria-current=step]{border-left:3px solid #2872bf;padding-left:3px}
@media(max-width:680px){.basic-path{grid-template-columns:1fr 1fr}.basic-path-current{grid-column:1/-1}.basic-nav-tools{grid-template-columns:1fr 1.5fr;align-items:center}.basic-nav-tools>span{grid-column:1/-1}}
@media(max-width:360px){.basic-path{grid-template-columns:1fr}.basic-path-current{grid-column:auto}}