:root {
  color-scheme: light dark;
  --bg: #f4f1ea;
  --ink: #1c1915;
  --muted: #6b655c;
  --paper: #fffdf8;
  --line: #d9d2c5;
  --accent: #1f4d3a;
  --accent-ink: #f4f1ea;
  --user: #e8efe9;
  --warn: #8a3b12;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #161411;
    --ink: #f4f1ea;
    --muted: #b0a89c;
    --paper: #221e19;
    --line: #3a342c;
    --accent: #8fbfa6;
    --accent-ink: #161411;
    --user: #2a332d;
    --warn: #f0a27a;
  }
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font: 16px/1.5 ui-sans-serif, system-ui, sans-serif;
  background: var(--bg);
  color: var(--ink);
  min-height: 100vh;
}
.shell {
  max-width: 720px;
  margin: 0 auto;
  padding: 24px 16px 32px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  gap: 16px;
}
header {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  align-items: flex-start;
}
h1 { margin: 0; font-size: 1.6rem; letter-spacing: -0.03em; }
.tag, .hint, .label { color: var(--muted); margin: 4px 0 0; font-size: 0.9rem; }
.status {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 16px;
  align-items: center;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 12px 14px;
}
#log {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 10px;
  min-height: 280px;
}
.msg {
  max-width: 92%;
  padding: 12px 14px;
  border-radius: 14px;
  border: 1px solid var(--line);
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}
.msg.assistant { background: var(--paper); align-self: flex-start; }
.msg.user { background: var(--user); align-self: flex-end; }
.msg .who { display: block; font-size: 0.75rem; color: var(--muted); margin-bottom: 4px; }
form {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
textarea {
  width: 100%;
  resize: vertical;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 12px;
  font: inherit;
  background: var(--paper);
  color: var(--ink);
}
.row { display: flex; justify-content: space-between; align-items: center; gap: 12px; }
button {
  font: inherit;
  border: 0;
  border-radius: 999px;
  padding: 8px 14px;
  background: var(--accent);
  color: var(--accent-ink);
  cursor: pointer;
}
button:disabled { opacity: 0.5; cursor: not-allowed; }
#banner { color: var(--warn); margin: 0; }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
}
h1 { max-width: 22ch; }
.toolbar, .limit {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 16px;
  align-items: end;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 12px 14px;
}
.field { display: flex; flex-direction: column; gap: 4px; min-width: 12rem; }
.field select {
  font: inherit;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 8px 10px;
  background: var(--paper);
  color: var(--ink);
}
#demo { background: transparent; color: var(--ink); border: 1px solid var(--line); }
.limit { flex-direction: column; align-items: flex-start; border-color: var(--warn); }
.limit h2 { margin: 0; font-size: 1.05rem; }
.limit p { margin: 0; color: var(--muted); }
.fineprint { color: var(--muted); font-size: 0.8rem; margin: 0; }