:root{color:#1f2933;--app-bg:#f0f2f5;--panel-bg:#fff;--border:#e2e8f0;--text:#1f2933;--muted:#64748b;--chat-bg:#efeae2;--bubble-in:#fff;--bubble-out:#d9fdd3;--bubble-system:#e2e8f0;--shadow:0 10px 30px #0f172a14;--bubble-shadow:0 2px 6px #0f172a1f;--sender-color:#0f172a;background-color:#f0f2f5;font-family:Inter,system-ui,-apple-system,sans-serif;font-weight:400;line-height:1.5}@media (prefers-color-scheme:dark){:root{color:#e2e8f0;--app-bg:#0f172a;--panel-bg:#111827;--border:#1f2937;--text:#e2e8f0;--muted:#94a3b8;--chat-bg:#0b1220;--bubble-in:#111827;--bubble-out:#1f2937;--bubble-system:#1e293b;--shadow:none;--bubble-shadow:none;--sender-color:#e2e8f0;background-color:#0f172a}}*{box-sizing:border-box}body{background:var(--app-bg);color:var(--text);margin:0}a{color:inherit}.app{background:var(--app-bg);min-height:100vh;color:var(--text);flex-direction:column;display:flex}.app-header{background:var(--panel-bg);border-bottom:1px solid var(--border)}.header-content{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:24px;max-width:1200px;margin:0 auto;padding:24px;display:flex}.header-title h1{margin:0 0 8px;font-size:clamp(24px,3vw,36px)}.header-title p{color:var(--muted);margin:0}.controls{flex-wrap:wrap;align-items:center;gap:12px;display:flex}.file-input{border:1px dashed var(--border);background:var(--panel-bg);cursor:pointer;color:var(--text);border-radius:10px;padding:10px 16px;font-weight:600;position:relative}.file-input input{opacity:0;cursor:pointer;position:absolute;inset:0}.input-group{color:var(--muted);flex-direction:column;gap:4px;font-size:12px;display:flex}.input-group input{border:1px solid var(--border);background:var(--panel-bg);color:var(--text);border-radius:8px;padding:8px 12px;font-size:14px}.secondary-btn{border:1px solid var(--border);background:var(--panel-bg);color:var(--text);cursor:pointer;border-radius:10px;padding:10px 16px;font-weight:600}.app-main{box-sizing:border-box;flex:1;grid-template-columns:minmax(0,1fr) minmax(0,1.4fr);gap:24px;width:100%;max-width:1200px;min-height:0;margin:0 auto;padding:24px;display:grid}.app-main.chat-only{flex-direction:column;max-width:100%;margin:0;display:flex}@media (width<=900px){.app-main{grid-template-columns:1fr}}.panel{background:var(--panel-bg);border:1px solid var(--border);box-shadow:var(--shadow);border-radius:16px;padding:20px}.info-panel ol{color:var(--text);margin-top:12px;padding-left:18px}.info-panel li+li{margin-top:8px}.info-meta{color:var(--muted);margin-top:12px}.error{color:#dc2626;margin-top:12px;font-weight:600}.chat-window{flex-direction:column;flex:1;min-height:60vh;display:flex}.chat-panel{flex-direction:column;min-height:0;display:flex}.app-main.chat-only .chat-panel{flex:1}.app-main.chat-only .chat-window{min-height:0}.chat-header{border-bottom:1px solid var(--border);justify-content:space-between;align-items:center;gap:12px;padding-bottom:12px;display:flex}.chat-header h3{margin:0 0 4px;font-size:18px}.chat-header p{color:var(--muted);margin:0;font-size:14px}.loading{color:var(--muted);font-size:14px}.chat-body{background:var(--chat-bg);border-radius:16px;flex:1;min-height:0;margin-top:12px;padding:16px;overflow-y:auto}.empty-state{text-align:center;color:var(--muted);padding:32px 12px}.message-row{margin-bottom:12px;display:flex}.message-row.incoming{justify-content:flex-start}.message-row.outgoing{justify-content:flex-end}.message-row.system{justify-content:center}.message-bubble{background:var(--bubble-in);max-width:min(75%,520px);box-shadow:var(--bubble-shadow);border-radius:14px;padding:10px 12px}.message-row.outgoing .message-bubble{background:var(--bubble-out)}.message-row.system .message-bubble{background:var(--bubble-system);text-align:center}.message-sender{color:var(--sender-color);margin-bottom:4px;font-size:12px;font-weight:600}.message-text{white-space:pre-wrap;word-break:break-word}.message-time{color:var(--muted);text-align:right;margin-top:6px;font-size:11px}.media-preview{margin-bottom:8px}.media-preview img,.media-preview video{border-radius:10px;width:100%}.media-preview audio{width:100%}.media-file{color:inherit;background:#0f172a14;border-radius:8px;align-items:center;gap:8px;padding:8px 10px;text-decoration:none;display:inline-flex}.media-file:hover{text-decoration:underline}