:root{
  --bg:#0b0b0d; --bg2:#141418; --line:#26262c; --fg:#e8e8ea; --muted:#8b8b93;
  --accent:#12b7f5; --user:#1f6feb; --bot:#1c1c22; --danger:#e05a5a;
  --safe-b: env(safe-area-inset-bottom, 0px);
}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html,body{height:100%}
body{
  margin:0;background:var(--bg);color:var(--fg);
  font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  font-size:16px;line-height:1.5;overscroll-behavior-y:contain;
}
.screen{position:fixed;inset:0;display:flex;flex-direction:column}
.hidden{display:none !important}

/* ---------- 登录 ---------- */
#login{align-items:center;justify-content:center;padding:24px}
.login-box{width:100%;max-width:360px;text-align:center}
.avatar{
  width:76px;height:76px;border-radius:22px;margin:0 auto 14px;
  background:linear-gradient(145deg,#12b7f5,#7d5cff);color:#fff;
  font-size:38px;font-weight:700;display:flex;align-items:center;justify-content:center;
  box-shadow:0 8px 24px rgba(18,183,245,.25);
}
.login-box h1{font-size:22px;margin:0 0 4px;font-weight:600}
.sub{color:var(--muted);font-size:13px;margin:0 0 22px}
.login-box input{
  width:100%;padding:14px 16px;margin-bottom:10px;border-radius:12px;
  border:1px solid var(--line);background:var(--bg2);color:var(--fg);font-size:16px;outline:none;
}
.login-box input:focus{border-color:var(--accent)}
button{font-family:inherit;font-size:16px;cursor:pointer;border:none}
.primary{
  width:100%;padding:14px;border-radius:12px;margin-top:6px;
  background:var(--accent);color:#04141c;font-weight:600;
}
.primary:active{opacity:.85}
.err{color:var(--danger);font-size:13px;min-height:18px;margin-top:10px}

/* ---------- 聊天 ---------- */
#chat{background:var(--bg)}
#chat header{
  display:flex;align-items:center;gap:10px;padding:calc(10px + env(safe-area-inset-top,0px)) 12px 10px;
  border-bottom:1px solid var(--line);background:rgba(11,11,13,.92);
  backdrop-filter:blur(12px);position:sticky;top:0;z-index:10;
}
#chat .title{flex:1;display:flex;flex-direction:column;line-height:1.15}
#chat .title span{font-weight:600;font-size:16px}
#chat .title small{color:var(--muted);font-size:11px}
.icon{
  width:38px;height:38px;border-radius:11px;background:var(--bg2);color:var(--fg);
  font-size:17px;display:flex;align-items:center;justify-content:center;
}
.icon:active{background:#202027}

#messages{
  flex:1;overflow-y:auto;padding:16px 14px 8px;display:flex;flex-direction:column;gap:10px;
  scrollbar-width:thin;
}
.row{display:flex;gap:8px;max-width:100%}
.row.user{justify-content:flex-end}
.bubble{
  max-width:82%;padding:10px 13px;border-radius:16px;white-space:pre-wrap;
  word-break:break-word;overflow-wrap:anywhere;font-size:15.5px;
}
.row.bot .bubble{background:var(--bot);border-bottom-left-radius:6px}
.row.user .bubble{background:var(--user);color:#fff;border-bottom-right-radius:6px}
.bubble img{max-width:100%;border-radius:10px;display:block;margin-top:6px}
.bubble .meta{color:var(--muted);font-size:11px;margin-top:4px}
.cursor::after{content:"▍";opacity:.7;animation:blink 1s steps(2) infinite}
@keyframes blink{50%{opacity:0}}
.sys{color:var(--muted);font-size:12.5px;text-align:center;margin:2px 0}

#composer{
  display:flex;gap:8px;align-items:flex-end;padding:10px 12px calc(10px + var(--safe-b));
  border-top:1px solid var(--line);background:rgba(11,11,13,.96);backdrop-filter:blur(12px);
}
#input{
  flex:1;resize:none;max-height:132px;padding:12px 14px;border-radius:20px;
  border:1px solid var(--line);background:var(--bg2);color:var(--fg);
  font-family:inherit;font-size:16px;line-height:1.4;outline:none;
}
#input:focus{border-color:#33333d}
.send{
  width:42px;height:42px;border-radius:50%;background:var(--accent);color:#04141c;
  font-size:19px;font-weight:700;flex:0 0 auto;
}
.send:disabled{background:#2a2a31;color:#5a5a63}
.spin{
  width:16px;height:16px;border:2px solid rgba(255,255,255,.25);border-top-color:var(--accent);
  border-radius:50%;animation:sp .7s linear infinite;display:inline-block;vertical-align:-2px;
}
@keyframes sp{to{transform:rotate(360deg)}}

/* ---------- 附件 ---------- */
.attach{font-size:19px;background:transparent;border:1px solid var(--line)}
.chips{
  display:flex;gap:8px;flex-wrap:wrap;padding:8px 12px 0;background:rgba(11,11,13,.96);
}
.chip{position:relative;display:flex;align-items:center;gap:6px;background:var(--bg2);
  border:1px solid var(--line);border-radius:10px;padding:4px 8px;font-size:12.5px;color:var(--muted)}
.chip img{width:44px;height:44px;object-fit:cover;border-radius:7px;display:block}
.chip .x{background:rgba(255,255,255,.08);color:var(--fg);border-radius:50%;
  width:20px;height:20px;line-height:1;font-size:13px;display:flex;align-items:center;justify-content:center}
.bubble .media{margin-top:6px}
.bubble .media img{max-width:100%;border-radius:10px;display:block}
.bubble .media audio{width:100%;margin-top:4px}
.bubble .media a.filelink{color:#8fd4ff;text-decoration:none;font-size:14px}