:root {
  --bg: #f3f5f9;
  --bg-2: #e8eef8;
  --panel: #ffffff;
  --line: #dce3ee;
  --text: #0f172a;
  --muted: #60708a;
  --accent: #0f766e;
  --accent-2: #0284c7;
  --chip: #ecf3ff;
  --warn: #b45309;
}
body.dark {
  --bg: #0d1423;
  --bg-2: #162133;
  --panel: #111b2c;
  --line: #29364d;
  --text: #e2e8f0;
  --muted: #98a7be;
  --accent: #14b8a6;
  --accent-2: #38bdf8;
  --chip: #1a2942;
  --warn: #f59e0b;
}
* { box-sizing: border-box; }
body { margin: 0; color: var(--text); font-family: "Segoe UI", "Helvetica Neue", sans-serif; background: linear-gradient(165deg, var(--bg), var(--bg-2)); }
.ambient { position: fixed; inset: 0; pointer-events: none; background: radial-gradient(circle at 8% 12%, rgba(14, 165, 233, 0.15), transparent 35%), radial-gradient(circle at 88% 0%, rgba(15, 118, 110, 0.18), transparent 32%); }
.app { display: grid; grid-template-columns: 320px 1fr; min-height: 100vh; position: relative; }
.sidebar { border-right: 1px solid var(--line); background: color-mix(in srgb, var(--panel) 92%, transparent); padding: 22px; backdrop-filter: blur(6px); }
.brand h1 { margin: 0; font-size: 1.4rem; }
.brand p { margin: 6px 0 0; color: var(--muted); font-size: 0.9rem; }
.panel { background: var(--panel); border: 1px solid var(--line); border-radius: 14px; padding: 14px; margin-top: 14px; }
.panel.compact { display: grid; gap: 8px; }
.stat { display: flex; justify-content: space-between; align-items: center; }
.stat span { color: var(--muted); font-size: 0.86rem; }
label { display: block; font-size: 0.82rem; font-weight: 600; margin-bottom: 6px; color: var(--muted); }
.mt { margin-top: 10px; }
input, select, textarea, button { width: 100%; border-radius: 10px; border: 1px solid var(--line); padding: 10px; font-size: 0.95rem; }
input, select, textarea { background: var(--panel); color: var(--text); }
textarea { resize: vertical; }
button { border: none; color: #fff; font-weight: 700; cursor: pointer; background: linear-gradient(135deg, var(--accent), var(--accent-2)); }
button.ghost { background: var(--chip); color: var(--text); border: 1px solid var(--line); }
button:disabled { opacity: 0.65; cursor: not-allowed; }
.row { display: flex; gap: 8px; }
.row.wrap { flex-wrap: wrap; align-items: center; }
.hint { font-size: 0.8rem; color: var(--muted); margin: 10px 0 0; }
.main { display: flex; flex-direction: column; min-height: 100vh; }
.chat-head { padding: 14px 18px; border-bottom: 1px solid var(--line); background: color-mix(in srgb, var(--panel) 88%, transparent); display: flex; justify-content: space-between; align-items: center; gap: 12px; }
.chat-head h2 { margin: 0; font-size: 1rem; }
.chat-head p { margin: 3px 0 0; color: var(--muted); font-size: 0.86rem; }
.head-search { width: 230px; }
.messages { flex: 1; overflow: auto; padding: 18px; display: flex; flex-direction: column; gap: 12px; }
.message-wrap { display: flex; flex-direction: column; gap: 6px; }
.message-wrap.user { align-items: flex-end; }
.message-wrap.assistant { align-items: flex-start; }
.message { max-width: min(85%, 900px); padding: 12px 14px; border-radius: 14px; line-height: 1.55; white-space: pre-wrap; }
.message.user { background: #0f172a; color: #fff; }
body.dark .message.user { background: #1e293b; }
.message.assistant { background: var(--panel); border: 1px solid var(--line); }
.message-wrap.favorite .message { border: 1px solid var(--warn); }
.message-wrap.hidden { display: none; }
.msg-meta { font-size: 0.75rem; color: var(--muted); display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.mini-btn { border: 1px solid var(--line); padding: 4px 8px; border-radius: 999px; background: var(--chip); color: var(--text); font-size: 0.72rem; cursor: pointer; }
.composer { border-top: 1px solid var(--line); padding: 14px; background: var(--panel); }
.composer-grid { display: grid; grid-template-columns: 1fr auto; gap: 10px; align-items: end; }
#prompt { min-height: 80px; }
.composer-foot { margin-top: 8px; display: flex; justify-content: space-between; gap: 10px; color: var(--muted); font-size: 0.84rem; }
@media (max-width: 920px) {
  .app { grid-template-columns: 1fr; }
  .sidebar { border-right: 0; border-bottom: 1px solid var(--line); }
  .chat-head { flex-direction: column; align-items: flex-start; }
  .head-search { width: 100%; }
  .message { max-width: 100%; }
}