:root{--paper:#f7f4ee;--paper-2:#efe9df;--ink:#2b2b29;--muted:#6f6a60;--clay:#a24a25;--clay-soft:#c5562e;--line:rgba(43,43,41,0.14);--card:#fffdf9;--serif:"Noto Serif SC",Georgia,serif;--sans:"Noto Sans SC",-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,sans-serif}*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--sans);line-height:1.7}.wrap{max-width:720px;margin:0 auto;padding:28px 20px 60px;min-height:100vh;display:flex;flex-direction:column}.brand{display:flex;align-items:baseline;gap:10px;padding-bottom:18px;border-bottom:1px solid var(--line)}.brand .zh{font-family:var(--serif);font-size:24px;letter-spacing:4px}.brand .en{font-size:12px;letter-spacing:2px;color:var(--muted)}.chat{flex:1 1;display:flex;flex-direction:column;gap:12px;padding:22px 0}.msg{max-width:85%;padding:11px 15px;border-radius:14px;font-size:15px;white-space:pre-wrap}.msg.user{align-self:flex-end;background:var(--clay);color:#faf4ee;border-bottom-right-radius:4px}.msg.assistant{align-self:flex-start;background:var(--card);border:1px solid var(--line);border-bottom-left-radius:4px}.composer{display:flex;gap:10px;position:-webkit-sticky;position:sticky;bottom:0;background:var(--paper);padding-top:12px}.composer input{flex:1 1;font-family:var(--sans);font-size:15px;padding:12px 14px;border:1px solid var(--line);border-radius:10px;background:var(--card);color:var(--ink)}.composer input:focus{outline:none;border-color:var(--clay)}.composer button{font-size:15px;padding:12px 22px;border:none;border-radius:10px;background:var(--clay);color:#faf4ee;cursor:pointer}.composer button:disabled{opacity:.6;cursor:default}.spec{margin-top:22px;background:var(--card);border:1px solid var(--line);border-radius:12px;padding:16px 18px}.spec h3{margin:0 0 10px;font-family:var(--serif);font-weight:500}.spec pre{margin:0;font-size:12.5px;overflow-x:auto;color:var(--ink)}