:root{--color-bg:#f5f5f7;--color-surface:#fff;--color-text:#1a1a2e;--color-muted:#6b7280;--color-accent:#c08497;--color-accent-soft:#f3d6dd;--color-user-bubble:#c08497;--color-user-text:#fff;--color-assistant-bubble:#f1f1f4;--color-assistant-text:#1a1a2e;--color-handoff-bg:#fff7ed;--color-handoff-border:#f59e0b;--color-handoff-action:#d97706;--color-error:#dc2626;--color-focus:#2563eb;--radius-sm:6px;--radius-md:12px;--radius-lg:18px;--shadow-sm:0 1px 2px #0000000d;--shadow-md:0 4px 12px #00000014;--max-content-width:480px;--font-stack:-apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, 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16px;font-size:12px;display:flex}.chat-shell__sources-label{flex-shrink:0}.chat-shell__sources-list{flex-wrap:wrap;gap:4px;margin:0;padding:0;list-style:none;display:flex}.chat-shell__sources-item{background:var(--color-assistant-bubble);border-radius:var(--radius-sm);padding:2px 8px;font-size:11px}.chat-shell__input-row{background:var(--color-surface);border-top:1px solid #eee;align-items:flex-end;gap:8px;padding:12px 16px;display:flex;position:sticky;bottom:0}.chat-shell__input-label{clip:rect(0, 0, 0, 0);white-space:nowrap;border:0;width:1px;height:1px;margin:-1px;padding:0;position:absolute;overflow:hidden}.chat-shell__input{resize:none;border-radius:var(--radius-md);background:var(--color-surface);color:var(--color-text);border:1px solid #d1d5db;flex:1;max-height:120px;padding:10px 12px;font-family:inherit;font-size:15px;line-height:1.5}.chat-shell__input:focus{outline:2px solid var(--color-focus);outline-offset:0;border-color:var(--color-focus)}.chat-shell__input:disabled{color:var(--color-muted);cursor:not-allowed;background:#f9fafb}.chat-shell__submit{background:var(--color-accent);color:var(--color-user-text);border-radius:var(--radius-md);border:none;flex-shrink:0;padding:10px 20px;font-size:15px;font-weight:500;transition:background .15s}.chat-shell__submit:hover:not(:disabled){background:#a86b7a}.chat-shell__submit:disabled{cursor:not-allowed;background:#d1d5db}.chat-message{width:100%;animation:.2s ease-out chat-message-enter;display:flex}.chat-message--user{justify-content:flex-end}.chat-message--assistant{justify-content:flex-start}.chat-message__bubble{border-radius:var(--radius-lg);word-break:break-word;overflow-wrap:anywhere;max-width:85%;padding:10px 14px;font-size:15px;line-height:1.5}.chat-message--user .chat-message__bubble{background:var(--color-user-bubble);color:var(--color-user-text);border-bottom-right-radius:4px}.chat-message--assistant 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16px;font-size:13px;line-height:1.55}.chat-shell__status--controlled{color:#9a3412;background:#fff7ed}.chat-shell__status--live{color:#166534;background:#ecfdf5}.handoff-card__actions{flex-wrap:wrap;gap:8px;display:flex}.handoff-card__action{background:var(--color-handoff-action);color:#fff;border-radius:var(--radius-sm);padding:8px 16px;font-size:14px;font-weight:500;text-decoration:none;transition:background .15s;display:inline-block}.handoff-card__action:hover{background:#b45309;text-decoration:none}.handoff-card__retry{border:1px solid var(--color-handoff-action);color:var(--color-handoff-action);border-radius:var(--radius-sm);font:inherit;cursor:pointer;background:0 0;padding:8px 16px;font-size:14px;font-weight:500}.handoff-card__retry:hover{background:#b4530914}@keyframes chat-message-enter{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}@keyframes typing-bounce{0%,80%,to{opacity:.5;transform:scale(0)}40%{opacity:1;transform:scale(1)}}@media (prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition-duration:.01ms!important;animation-duration:.01ms!important;animation-iteration-count:1!important}}@media (max-width:360px){.chat-shell__header,.chat-shell__messages{padding:12px}.chat-shell__input-row{padding:10px 12px}.chat-message__bubble{max-width:92%;font-size:14px}}