/* Catalog extensions; shared catalog and material-page chrome remain canonical. */
.mid-navigation{display:flex;align-items:center;flex-wrap:wrap;gap:10px;margin:0 0 16px}
.mid-navigation .theory-back-btn{box-sizing:border-box;min-height:42px;display:inline-flex;align-items:center}
.mid-navigation [aria-current="page"]{background:#edf5ff;border-color:#7b9cbe;color:#284f7d}
.mid-intro{color:#617389;line-height:1.6;margin:18px 0}
.material-catalog-page .mid-source{margin:20px 0 24px}
.mid-source>summary{cursor:pointer;padding:18px 20px;color:#315f8f;font-weight:600;line-height:1.5}
.mid-source-body{padding:0 20px 16px;line-height:1.6}
.mid-source-body p{margin:0 0 12px}
.mid-source-note{color:#66778b;font-size:14px;line-height:1.6}
.mid-topic-page{background:#f5f8fb;color:#23334b}
.mid-topic-shell{box-sizing:border-box;width:calc(100% - 32px);max-width:1080px;margin:0 auto;padding:22px 0 48px}
/* Established z10-theory sheet/body/block pattern and canonical task mounts. */
.mid-topic-shell .theory-sheet{margin-top:20px;border:1px solid #dbe7f4;border-radius:14px;background:#fff;box-shadow:0 12px 34px rgba(35,51,75,.08);overflow:hidden}
.mid-topic-shell .sheet-body{display:grid;gap:0;padding:12px}
.mid-topic-shell .theory-block{border:1px solid #dbe7f4;border-radius:12px;background:#fff;overflow:hidden}
.mid-topic-shell .theory-block__head{display:flex;align-items:center;gap:8px;margin:0;padding:8px 10px;border-bottom:1px solid #dbe7f4;font-size:15px;font-weight:900}
.mid-topic-shell .theory-block__head:before{content:"";width:10px;height:10px;flex-shrink:0;border-radius:50%;background:#3f6ea5}
.mid-topic-shell .head-green .theory-block__head:before{background:#2f8f6b}
.mid-topic-shell .theory-block__body{padding:10px;font-size:17px;line-height:1.6}
.mid-topic-shell .theory-block__body p{margin:6px 0 12px}
.mid-topic-shell .theory-block{margin-bottom:24px}
.mid-topic-shell .theory-block:last-of-type{margin-bottom:0}
.mid-topic-shell .theory-block__body li{margin-bottom:8px}
/* Table pattern reused from z7-theory. Horizontal scrolling remains local. */
.mid-topic-shell .speech-table-wrap{overflow-x:auto;margin:12px 0}
.mid-topic-shell .speech-table{width:100%;min-width:580px;border-collapse:collapse;table-layout:fixed}
.mid-topic-shell .speech-table th,.mid-topic-shell .speech-table td{padding:10px;border:1px solid #dfe6ef;text-align:left;vertical-align:top}
.mid-topic-shell .speech-table th{background:#edf5ff}
/* The same mnemonic-figure pattern as z10-theory; images belong to lesson snapshots. */
.mid-topic-shell .mnemonic-figure{display:flex;align-items:center;justify-content:center;margin:16px auto 8px;min-width:0;max-width:720px}
.mid-topic-shell .mnemonic-figure img{display:block;width:100%;max-width:100%;min-width:0;height:auto;border-radius:8px}
.mid-topic-source{padding:0 10px;color:#66778b;font-size:14px;line-height:1.6}
@media(max-width:600px){.mid-topic-shell{width:100%;padding:12px}.mid-navigation{gap:8px}.mid-source-body{padding:0 16px 12px}}