:root{--bg:#f3f5fa;--card:#fff;--ink:#1e293b;--muted:#64748b;--accent:#4f46e5;--accent2:#7c3aed;--line:#dbe1ec;--ok:#047857;--bad:#b42318;--safe-b:env(safe-area-inset-bottom,0px);--safe-t:env(safe-area-inset-top,0px)}*{box-sizing:border-box}html,body{margin:0;min-height:100%;font-family:-apple-system,PingFang HK,Noto Sans TC,sans-serif;background:var(--bg);color:var(--ink)}body{padding-bottom:calc(28px + var(--safe-b))}button,input,textarea,select{font:inherit}button{cursor:pointer}button:disabled{opacity:.5;cursor:not-allowed}.hidden{display:none!important}.topbar{position:sticky;top:0;z-index:20;display:flex;align-items:center;gap:16px;padding:calc(10px + var(--safe-t)) 16px 10px;background:#fffffff7;border-bottom:1px solid var(--line)}.brand{font-size:19px;font-weight:750;white-space:nowrap}.brand-sub{display:block;font-size:11px;color:var(--muted);font-weight:500}.tabs{display:flex;gap:6px}.tab{min-height:44px;min-width:76px;padding:0 15px;border:1px solid var(--line);border-radius:999px;background:#fff;color:var(--muted)}.tab.active{color:#fff;border-color:transparent;background:linear-gradient(135deg,var(--accent),var(--accent2))}.ai-status{margin-left:auto;padding:5px 10px;border-radius:999px;background:#eef2ff;color:#4338ca;font-size:12px;white-space:nowrap}.ai-status.error{background:#fef3f2;color:var(--bad)}.ai-notice{margin:10px auto 0;width:min(860px,calc(100% - 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