:root{--bg: #ffffff;--bg-secondary: #f4f5f7;--text: #1a1a1a;--text-muted: #6b7280;--border: #e2e4e8;--accent: #4f46e5;--accent-contrast: #ffffff;--danger: #dc2626;--online: #22c55e;--away: #eab308;--busy: #ef4444}[data-theme=dark]{--bg: #17181c;--bg-secondary: #1f2126;--text: #e8e8ea;--text-muted: #9ca3af;--border: #2c2e35;--accent: #818cf8;--accent-contrast: #17181c;--danger: #f87171;--online: #4ade80;--away: #facc15;--busy: #f87171}*{box-sizing:border-box}body{margin:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;background:var(--bg);color:var(--text)}.app-shell{display:flex;height:100vh}.sidebar{width:260px;background:var(--bg-secondary);border-right:1px solid var(--border);display:flex;flex-direction:column}.main-panel{flex:1;display:flex;flex-direction:column;min-width:0}.channel-item{padding:10px 16px;cursor:pointer;display:flex;align-items:center;gap:8px;border-radius:6px;margin:2px 8px}.channel-item:hover{background:var(--border)}.channel-item.active{background:var(--accent);color:var(--accent-contrast)}.presence-dot{width:8px;height:8px;border-radius:50%;display:inline-block;flex-shrink:0}.presence-dot.online{background:var(--online)}.presence-dot.away{background:var(--away)}.presence-dot.busy{background:var(--busy)}.presence-dot.offline{background:var(--text-muted)}.message-thread{flex:1;overflow-y:auto;padding:16px}.message-row{margin-bottom:12px}.message-sender{font-weight:600;margin-right:8px}.message-time{color:var(--text-muted);font-size:12px}.message-body{white-space:pre-wrap;word-break:break-word}.message-input-bar{border-top:1px solid var(--border);padding:12px 16px;display:flex;gap:8px}.message-input-bar input{flex:1;padding:10px 12px;border-radius:8px;border:1px solid var(--border);background:var(--bg);color:var(--text)}button{cursor:pointer;border:none;border-radius:8px;padding:8px 16px;background:var(--accent);color:var(--accent-contrast);font-weight:600}button.secondary{background:var(--bg-secondary);color:var(--text);border:1px solid var(--border)}button:disabled{opacity:.5;cursor:not-allowed}.auth-page{display:flex;align-items:center;justify-content:center;height:100vh}.auth-card{width:360px;padding:32px;border-radius:12px;border:1px solid var(--border);background:var(--bg-secondary)}.auth-card input{width:100%;padding:10px 12px;margin-bottom:12px;border-radius:8px;border:1px solid var(--border);background:var(--bg);color:var(--text)}.auth-card .error{color:var(--danger);font-size:14px;margin-bottom:12px}.auth-tabs{display:flex;gap:8px;margin-bottom:16px}.auth-tabs button{flex:1}.modal-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#00000080;display:flex;align-items:center;justify-content:center;z-index:100}.modal-card{background:var(--bg);border-radius:12px;padding:24px;width:340px;border:1px solid var(--border)}.call-room{flex:1;display:flex;flex-direction:column;background:#000}.call-video-grid{flex:1;display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:8px;padding:8px}.call-video-grid video{width:100%;height:100%;object-fit:cover;border-radius:8px;background:#222}.call-controls{display:flex;gap:12px;justify-content:center;padding:16px;background:var(--bg-secondary)}