:root{--bg:#f6f7f9;--panel:#fff;--text:#16181d;--muted:#667085;--line:#dfe3ea;--accent:#2457d6;--accent-t:#fff;--user:#e8eefc;--tool:#f1f3f6;--err:#b42318;--code:#f1f3f6}
@media (prefers-color-scheme:dark){:root:not([data-theme=light]){--bg:#0e1116;--panel:#161a22;--text:#e6e8ec;--muted:#98a1b0;--line:#272d38;--accent:#6e93ff;--accent-t:#0b1020;--user:#1d2a4a;--tool:#1c212b;--err:#ff7b72;--code:#1c212b}}
:root[data-theme=dark]{--bg:#0e1116;--panel:#161a22;--text:#e6e8ec;--muted:#98a1b0;--line:#272d38;--accent:#6e93ff;--accent-t:#0b1020;--user:#1d2a4a;--tool:#1c212b;--err:#ff7b72;--code:#1c212b}
*{box-sizing:border-box}
html,body{height:100%;margin:0}
body{font:16px/1.5 system-ui,-apple-system,Segoe UI,Roboto,sans-serif;background:var(--bg);color:var(--text);-webkit-text-size-adjust:100%}
[hidden]{display:none!important}
button{font:inherit;cursor:pointer;border:1px solid var(--line);background:var(--panel);color:var(--text);border-radius:10px;padding:0 14px;min-height:44px}
button:hover{border-color:var(--accent)}
button:focus-visible,textarea:focus-visible,input:focus-visible,summary:focus-visible,li:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
button.primary{background:var(--accent);color:var(--accent-t);border-color:var(--accent);font-weight:600}
button.danger{border-color:var(--err);color:var(--err)}
button.small{min-height:36px;padding:0 12px}
button.icon{min-width:44px;padding:0;font-size:20px;background:transparent;border-color:transparent}
button.link{background:none;border:none;color:var(--muted);min-height:44px;padding:0 8px;text-decoration:underline}
.muted{color:var(--muted)}.err{color:var(--err);min-height:1.4em;margin:.4rem 0 0}
.login{min-height:100%;display:grid;place-items:center;padding:20px}
.login-card{background:var(--panel);border:1px solid var(--line);border-radius:16px;padding:24px;width:100%;max-width:380px;display:grid;gap:12px}
.login-card h1{margin:0}
input,textarea{font:inherit;color:var(--text);background:var(--panel);border:1px solid var(--line);border-radius:10px;padding:10px 12px;width:100%}
.app{height:100dvh;display:grid;grid-template-columns:300px 1fr}
.side{background:var(--panel);border-right:1px solid var(--line);display:flex;flex-direction:column;min-height:0}
.side-head{display:flex;align-items:center;gap:8px;padding:12px;border-bottom:1px solid var(--line)}
.side-head strong{flex:1}
.session-list{list-style:none;margin:0;padding:6px;overflow:auto;flex:1}
.session-list li{padding:10px;border-radius:10px;cursor:pointer;min-height:44px}
.session-list li:hover{background:var(--tool)}
.session-list li.on{background:var(--user)}
.session-list .t{display:block;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.session-list .m{font-size:12px;color:var(--muted)}
.side-foot{display:flex;justify-content:space-between;border-top:1px solid var(--line);padding:4px 8px}
.main{display:flex;flex-direction:column;min-height:0;min-width:0}
.top{display:flex;align-items:center;gap:8px;padding:6px 12px;border-bottom:1px solid var(--line);background:var(--panel);padding-top:max(6px,env(safe-area-inset-top))}
.title{flex:1;font-weight:600;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.chip{background:var(--user);border-radius:999px;padding:2px 10px;font-size:13px}
.log{flex:1;overflow:auto;padding:14px 16px;display:flex;flex-direction:column;gap:12px;overscroll-behavior:contain}
.msg{position:relative;max-width:100%;border-radius:14px;padding:10px 14px;overflow-wrap:anywhere}
.msg.user{background:var(--user);align-self:flex-end;max-width:min(92%,900px);white-space:pre-wrap}
.msg.assistant{background:var(--panel);border:1px solid var(--line);align-self:stretch}
.msg.assistant p{margin:.4em 0}.msg.assistant h1,.msg.assistant h2,.msg.assistant h3{margin:.7em 0 .3em;font-size:1.05em}
.msg.assistant ul,.msg.assistant ol{margin:.4em 0;padding-left:1.4em}
.msg pre{background:var(--code);border-radius:10px;padding:10px;overflow:auto;margin:.5em 0;position:relative;font-size:13.5px;-webkit-overflow-scrolling:touch}
.msg code{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-size:.92em}
.msg :not(pre)>code{background:var(--code);border-radius:5px;padding:1px 5px}
.msg a{color:var(--accent)}
.copy{position:absolute;top:6px;right:6px;min-height:32px;padding:0 10px;font-size:13px;opacity:.9}
.msg.assistant>.copy{position:static;display:block;margin:6px 0 0 auto;min-height:36px}
.tool{background:var(--tool);border-radius:10px;padding:0 12px;font-size:14px;align-self:stretch}
.tool summary{cursor:pointer;min-height:44px;display:flex;align-items:center;gap:8px;list-style:none;color:var(--muted);overflow:hidden}
.tool summary::-webkit-details-marker{display:none}
.tool summary .s{overflow:hidden;text-overflow:ellipsis;white-space:nowrap;flex:1}
.tool.bad summary{color:var(--err)}
.tool pre{font-size:12.5px;max-height:320px}
.notice{align-self:center;font-size:13px;color:var(--muted)}
.empty{margin:auto;text-align:center;color:var(--muted);max-width:30ch}
.composer{display:flex;gap:8px;align-items:flex-end;padding:10px 12px calc(10px + env(safe-area-inset-bottom));border-top:1px solid var(--line);background:var(--panel)}
.composer textarea{resize:none;max-height:40dvh;min-height:44px}
.composer button{min-height:44px;min-width:76px}
.only-mobile{display:none}
@media (max-width:767px){
  .app{grid-template-columns:1fr}
  .side{position:fixed;inset:0 20% 0 0;z-index:20;transform:translateX(-102%);transition:transform .18s;max-width:340px;width:84%}
  .side.open{transform:none}
  .scrim{position:fixed;inset:0;background:rgba(0,0,0,.4);z-index:10}
  .only-mobile{display:inline-block}
  .log{padding:10px 10px}
  .msg.user{max-width:94%}
}
@media (min-width:1100px){.app{grid-template-columns:340px 1fr}.log{padding:18px 8%}}