:root{--bg:#0d1117;--bg-elev:#161b22;--border:#2d333b;--text:#e6edf3;--text-dim:#9aa4af;--accent:#3fb97f;--accent-dim:#2a7d57;--danger:#e5534b;--maxw:960px}*{box-sizing:border-box;margin:0;padding:0}html{color-scheme:dark}body{background:var(--bg);color:var(--text);font-family:var(--font-noto),"Hiragino Sans","Yu Gothic",sans-serif;line-height:1.8;-webkit-font-smoothing:antialiased}a{color:var(--accent);text-decoration:none}a:hover{text-decoration:underline}main{max-width:var(--maxw);margin:0 auto;padding:48px 20px 80px}h1{font-size:1.9rem;line-height:1.4;margin-bottom:16px}h2{font-size:1.3rem;margin:40px 0 12px;padding-bottom:8px;border-bottom:1px solid var(--border)}p,ul{margin-bottom:14px}ul{padding-left:1.4em}.card{background:var(--bg-elev);border:1px solid var(--border);border-radius:12px;padding:20px}.grid3{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));grid-gap:16px;gap:16px}.btn{display:inline-block;background:var(--accent);color:#04110b;font-weight:700;border-radius:8px;padding:10px 20px}.btn:hover{text-decoration:none;opacity:.9}.note{font-size:.85rem}.note,.tab{color:var(--text-dim)}.tab{display:inline-block;padding:10px 20px;border:1px solid var(--border);border-radius:8px}.tab:hover{text-decoration:none;color:var(--text)}label{display:block;font-weight:700;margin-bottom:20px}textarea{display:block;width:100%;margin-top:8px;background:var(--bg-elev);color:var(--text);border:1px solid var(--border);border-radius:8px;padding:10px 12px;font:inherit;line-height:1.6;resize:vertical}textarea:disabled{opacity:.6}button.btn{font:inherit;border:none;cursor:pointer}button.btn:disabled{opacity:.6;cursor:not-allowed}.admin-stats{display:flex;gap:16px;flex-wrap:wrap;margin-bottom:8px}.admin-stat-card{background:var(--bg-elev);border:1px solid var(--border);border-radius:12px;padding:16px 24px;text-align:center;min-width:140px}.admin-stat-value{display:block;font-size:1.8rem;font-weight:700}.admin-stat-label{display:block;color:var(--text-dim);font-size:.85rem;margin-top:4px}.admin-lesson-filter{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:16px}.admin-lesson-filter a{padding:6px 14px;border:1px solid var(--border);border-radius:999px;color:var(--text-dim);font-size:.85rem}.admin-lesson-filter a:hover{text-decoration:none;color:var(--text)}.admin-filter-active{background:var(--accent);color:#04110b!important;border-color:var(--accent)!important;font-weight:700}.admin-feedback-list{display:flex;flex-direction:column;gap:12px;margin-bottom:40px}.admin-card{background:var(--bg-elev);border:1px solid var(--border);border-radius:12px;padding:16px 20px}.admin-card-head{display:flex;gap:10px;align-items:baseline;flex-wrap:wrap;margin-bottom:8px}.admin-badge{display:inline-block;background:var(--accent-dim);color:var(--text);border-radius:6px;padding:2px 8px;font-size:.75rem}.admin-badge-danger{background:var(--danger);color:#fff}.admin-name{font-weight:700}.admin-time{color:var(--text-dim);font-size:.8rem;margin-left:auto}.admin-pre{white-space:pre-wrap;word-break:break-word;margin-bottom:0}.admin-question{margin-top:10px;border:1px solid var(--accent-dim);border-radius:8px;padding:10px 14px;background:rgba(63,185,127,.08)}.admin-question-label{font-weight:700;margin-bottom:4px}.admin-conversations{display:flex;flex-direction:column;gap:24px}.admin-conversation h3{font-size:1rem;margin-bottom:10px}.admin-talk{display:flex;flex-direction:column;gap:8px}.admin-bubble{max-width:70%;border-radius:12px;padding:8px 14px}.admin-bubble-user{align-self:flex-start;background:var(--bg-elev);border:1px solid var(--border)}.admin-bubble-assistant{align-self:flex-end;background:var(--accent-dim)}.admin-bubble-escalated{border:1px solid var(--danger);background:rgba(229,83,75,.12)}