:root {
  --bg: #f6f7f9; --panel: #ffffff; --text: #1b1f24; --muted: #5d6673; --line: #dfe3e8;
  --accent: #1f5fd1; --accent-text: #ffffff; --user: #e8f0fe; --err: #b42318; --err-bg: #fdecea; --warn-bg: #fff4d6;
  --radius: 12px;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #14171b; --panel: #1c2026; --text: #e8eaed; --muted: #9aa3ae; --line: #2c333b;
    --accent: #6ea0ff; --accent-text: #0b1220; --user: #1d2b45; --err: #ff8a80; --err-bg: #3a1f1d; --warn-bg: #3a3014;
  }
}
* { box-sizing: border-box; }
html, body { height: 100%; }
body { margin: 0; background: var(--bg); color: var(--text); font: 16px/1.5 system-ui, -apple-system, "Segoe UI", sans-serif;
       display: flex; flex-direction: column; }
.bar { display: flex; align-items: center; gap: 12px; padding: 10px 16px; background: var(--panel); border-bottom: 1px solid var(--line); }
.brand { font-weight: 650; letter-spacing: .2px; }
.who { color: var(--muted); font-size: 14px; flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.actions { display: flex; gap: 8px; margin-left: auto; }
main { flex: 1; width: 100%; max-width: 900px; margin: 0 auto; padding: 16px; display: flex; flex-direction: column; min-height: 0; }
.card { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; }
.narrow { max-width: 420px; margin: 8vh auto 0; width: 100%; }
h1 { font-size: 22px; margin: 0 0 6px; }
.muted { color: var(--muted); }
label { display: block; margin: 14px 0 0; font-size: 14px; color: var(--muted); }
input, textarea { width: 100%; margin-top: 6px; padding: 10px 12px; font: inherit; color: var(--text); background: var(--bg);
                  border: 1px solid var(--line); border-radius: 10px; }
input:focus, textarea:focus { outline: 2px solid var(--accent); outline-offset: 1px; }
button { font: inherit; cursor: pointer; border-radius: 10px; border: 1px solid var(--accent); background: var(--accent);
         color: var(--accent-text); padding: 10px 16px; }
button:disabled { opacity: .55; cursor: default; }
button.ghost { background: transparent; color: var(--text); border-color: var(--line); padding: 6px 12px; font-size: 14px; }
#loginForm button { margin-top: 18px; width: 100%; }
.error { color: var(--err); background: var(--err-bg); border-radius: 8px; padding: 8px 10px; margin: 12px 0 0; font-size: 14px; }
#chat { display: flex; flex-direction: column; flex: 1; min-height: 0; }
.log { flex: 1; overflow-y: auto; padding: 4px 0 12px; display: flex; flex-direction: column; gap: 14px; min-height: 120px; }
.msg { max-width: 100%; padding: 12px 14px; border-radius: var(--radius); border: 1px solid var(--line); background: var(--panel); overflow-wrap: anywhere; }
.msg.user { background: var(--user); align-self: flex-end; max-width: 85%; white-space: pre-wrap; }
.msg.bot > :first-child { margin-top: 0; } .msg.bot > :last-child { margin-bottom: 0; }
.msg h4 { margin: 14px 0 6px; font-size: 16px; }
.msg p { margin: 8px 0; } .msg ul, .msg ol { margin: 8px 0; padding-left: 22px; }
.msg code { background: var(--bg); border: 1px solid var(--line); padding: 1px 5px; border-radius: 5px; font-size: .9em; }
.tablewrap { overflow-x: auto; margin: 10px 0; border: 1px solid var(--line); border-radius: 8px; }
table { border-collapse: collapse; width: 100%; font-size: 14px; }
th, td { padding: 6px 10px; text-align: left; border-bottom: 1px solid var(--line); white-space: nowrap; }
th { background: var(--bg); font-weight: 600; } tr:last-child td { border-bottom: 0; }
.used { margin-top: 10px; font-size: 13px; color: var(--muted); }
.used summary { cursor: pointer; }
.used ul { margin: 6px 0 0; padding-left: 18px; }
.pending { color: var(--muted); font-style: italic; }
.notice { background: var(--warn-bg); border-radius: 8px; padding: 10px 12px; margin-bottom: 10px; font-size: 14px; }
.examples { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 10px; }
.examples button { background: var(--panel); color: var(--text); border-color: var(--line); font-size: 14px; padding: 6px 12px; text-align: left; }
.ask { display: flex; gap: 8px; align-items: flex-end; }
.ask textarea { margin: 0; resize: none; max-height: 160px; }
.foot { font-size: 12px; margin: 8px 0 0; }
[hidden] { display: none !important; }
@media (max-width: 560px) { main { padding: 10px; } .card { padding: 18px; } .msg.user { max-width: 95%; } }