:root{--ic-sky:#0EA5E9;--ic-sky-text:#0369A1;--ic-navy:#0F172A;--ic-body:#334155;--ic-sub:#64748B;--ic-label:#94A3B8;--ic-silver:#C0C0C0;--ic-line:#E2E8F0}*{box-sizing:border-box}html,body{margin:0;background:#fff;color:var(--ic-body);font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;font-size:14px}.ic-top{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:10px 16px;border-bottom:1.5px solid transparent;border-image:linear-gradient(90deg,transparent,var(--ic-silver),transparent) 1}.ic-brand{display:flex;align-items:center;gap:8px;text-decoration:none;color:var(--ic-navy);font-weight:800;letter-spacing:.02em}.ic-brand b{color:var(--ic-navy)}.ic-brand small{font-weight:600;color:var(--ic-sub);margin-left:6px}.ic-top-right{display:flex;align-items:center;gap:14px}.ic-user{color:var(--ic-sub)}.ic-live{font-size:12px;font-weight:700;color:var(--ic-sub)}.ic-live[data-state=live]{color:#047857}.ic-live[data-state=polling]{color:#b45309}.ic-link{background:none;border:0;color:var(--ic-sky-text);font:inherit;font-weight:700;cursor:pointer;padding:6px 8px;min-height:36px}.ic-btn{min-height:40px;padding:8px 16px;border-radius:10px;border:1px solid var(--ic-sky-text);background:var(--ic-sky-text);color:#fff;font:inherit;font-weight:700;cursor:pointer}.ic-main{max-width:1280px;margin:0 auto;padding:16px}.ic-state{padding:40px 16px;text-align:center;color:var(--ic-sub)}.ic-state h1{color:var(--ic-navy);font-size:22px;margin:0 0 8px}.ic-toolbar{display:flex;flex-wrap:wrap;gap:10px;align-items:center;margin:0 0 12px}.ic-toolbar input,.ic-toolbar select{min-height:40px;padding:6px 10px;border:1px solid var(--ic-line);border-radius:10px;font:inherit;color:var(--ic-body);background:#fff}.ic-toolbar input{flex:1 1 220px}.ic-count{color:var(--ic-sub);font-size:13px}.ic-split{display:grid;grid-template-columns:minmax(0,1fr) minmax(320px,440px);gap:16px}@media(max-width:600px){.ic-user,.ic-brand small{display:none}}@media(max-width:900px){.ic-split{grid-template-columns:1fr}.ic-detail{position:fixed;inset:auto 0 0;max-height:70vh;overflow:auto;background:#fff;box-shadow:0 -8px 24px #0f172a2e;border-radius:16px 16px 0 0;z-index:5}.ic-detail-empty{display:none}}.ic-roster-wrap{overflow-x:auto}.ic-roster{width:100%;border-collapse:collapse}.ic-roster th{text-align:left;font-size:11px;letter-spacing:.06em;text-transform:uppercase;color:var(--ic-sub);padding:8px 10px;border-bottom:1px solid var(--ic-line)}.ic-roster td{padding:10px;border-bottom:1px solid var(--ic-line);vertical-align:top}.ic-roster tr{cursor:pointer}.ic-roster tr:hover,.ic-roster tr[aria-selected=true]{background:#0ea5e90f}.ic-roster tr[aria-selected=true] td:first-child{box-shadow:inset 3px 0 0 var(--ic-sky)}.ic-name{color:var(--ic-navy);font-weight:700;display:block}.ic-email{color:var(--ic-sub);font-size:12px;display:block;overflow-wrap:anywhere}.ic-dot{display:inline-block;width:8px;height:8px;border-radius:50%;background:var(--ic-silver);margin-right:6px;vertical-align:middle}.ic-dot.on{background:#10b981;box-shadow:0 0 0 3px #10b98133}.ic-now{font-size:12.5px}.ic-now small{display:block;color:var(--ic-sub)}.ic-ok{color:#047857;font-weight:700}.ic-bad{color:#dc2626;font-weight:700}.ic-empty{color:var(--ic-sub);text-align:center;padding:24px}.ic-detail{border:1px solid var(--ic-line);border-radius:14px;padding:14px;align-self:start;position:sticky;top:12px}.ic-detail-empty{color:var(--ic-sub)}.ic-detail-head{display:flex;justify-content:space-between;gap:10px}.ic-detail h2{margin:0;font-size:18px;color:var(--ic-navy)}.ic-detail h3{font-size:13px;letter-spacing:.06em;text-transform:uppercase;color:var(--ic-sub);margin:16px 0 8px}.ic-muted{color:var(--ic-sub);font-size:12.5px}.ic-stats{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px;margin-top:12px}.ic-stat{padding:10px;border:1px solid var(--ic-line);border-radius:10px}.ic-stat span{display:block;font-size:10.5px;text-transform:uppercase;letter-spacing:.06em;color:var(--ic-sub)}.ic-stat strong{display:block;font-size:18px;color:var(--ic-navy);margin-top:2px}.ic-thread{display:flex;flex-direction:column;gap:6px;max-height:260px;overflow:auto;padding:2px 0 8px}.ic-thread:empty:before{content:"No messages yet. Say hello.";color:var(--ic-sub);font-size:12.5px}.ic-m{max-width:88%;padding:8px 11px;border-radius:12px;font-size:13.5px;line-height:1.45;white-space:pre-wrap;overflow-wrap:anywhere}.ic-m small{display:block;font-size:11px;color:var(--ic-sub);margin-top:2px}.ic-m.from-instructor{align-self:flex-end;background:#0ea5e91a;border:1px solid rgba(14,165,233,.3);color:var(--ic-navy)}.ic-m.from-student{align-self:flex-start;background:#f1f5f9;color:var(--ic-body)}.ic-m.ic-new{animation:icIn .4s ease}.ic-m .ic-ctx{display:block;font-size:11px;color:var(--ic-sky-text);margin-bottom:2px}.ic-compose{display:grid;gap:8px;margin:0 0 6px}.ic-compose textarea{width:100%;padding:10px;border:1px solid var(--ic-line);border-radius:10px;font:inherit;font-size:14px;resize:vertical;min-height:56px}.ic-compose-row{display:flex;align-items:center;justify-content:space-between;gap:10px;flex-wrap:wrap}.ic-ctx-label{font-size:12.5px;color:var(--ic-body);display:flex;align-items:center;gap:6px;min-height:40px}.ic-ctx-label input{width:16px;height:16px}.ic-unread{display:inline-block;min-width:18px;padding:1px 6px;border-radius:999px;background:#b45309;color:#fff;font-size:11px;font-weight:800;margin-left:6px;vertical-align:middle}.ic-feed{list-style:none;margin:0;padding:0;max-height:60vh;overflow:auto}.ic-feed li{padding:10px 0;border-top:1px solid var(--ic-line);display:grid;grid-template-columns:22px 1fr;gap:8px}.ic-feed li.ic-new{animation:icIn .4s ease}@keyframes icIn{0%{background:#0ea5e924}to{background:transparent}}.ic-feed .ic-mark{font-weight:900}.ic-feed .ic-meta{font-size:11.5px;color:var(--ic-sub)}.ic-feed .ic-stem{margin-top:3px;color:var(--ic-body);overflow-wrap:anywhere}.ic-feed .ic-skill{font-size:12px;color:var(--ic-navy);font-weight:600}@media(prefers-reduced-motion:reduce){.ic-feed li.ic-new{animation:none}}.ic-media-row{display:flex;gap:8px;flex-wrap:wrap}.ic-btn-ghost{min-height:40px;padding:8px 12px;border-radius:10px;border:1px solid var(--ic-line);background:#fff;color:var(--ic-sky-text);font:inherit;font-size:13px;font-weight:700;cursor:pointer;display:inline-flex;align-items:center;gap:6px}.ic-btn-ghost[aria-pressed=true]{border-color:#b91c1c;color:#b91c1c}.ic-file-label:focus-within{outline:2px solid var(--ic-sky);outline-offset:2px}.ic-pending{display:flex;align-items:center;gap:10px;flex-wrap:wrap;padding:8px 10px;border:1px dashed var(--ic-line);border-radius:10px;font-size:13px;color:var(--ic-body)}.ic-pending[hidden]{display:none}.ic-pending audio{max-width:100%;height:36px}.qm-att{margin:4px 0 6px}.qm-att audio,.qm-att video{display:block;width:280px;max-width:100%;border-radius:8px}.qm-att img{display:block;max-width:min(100%,320px);max-height:240px;border-radius:8px;border:1px solid var(--ic-line)}.qm-att-meta,.qm-att-loading{display:block;font-size:11px;color:var(--ic-sub)}.qm-att-error{font-size:12px;color:#b91c1c}.qm-att-file{font-weight:700;color:var(--ic-sky-text)}