:root {
  --bg: #FFF8EF;
  --card: #FFFFFF;
  --ink: #2F2A25;
  --muted: #8A7F73;
  --line: #EDE2D5;
  --accent: #E8702A;
  --accent-soft: #FDEBDD;
  --mumi: #F5F1EB;
  --ok: #2E8B57;
  --error: #C9433F;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #1E1B18; --card: #2A2622; --ink: #F1ECE6; --muted: #A89D91; --line: #3A342E;
    --accent: #F08A48; --accent-soft: #4A3222; --mumi: #34302B; --ok: #6CC18F; --error: #F07A76;
    color-scheme: dark;
  }
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 15px/1.6 -apple-system, "PingFang SC", "Helvetica Neue", sans-serif; }
[hidden] { display: none !important; }
h1 { font-size: 26px; margin: 0 0 8px; }
h2 { font-size: 18px; margin: 0; }
h3 { font-size: 16px; margin: 0; }
.muted { color: var(--muted); }
.small { font-size: 13px; }
.error { color: var(--error); min-height: 1.4em; }
.ok { color: var(--ok); min-height: 1.4em; }
.hint { color: var(--muted); font-size: 13px; margin: -6px 0 12px; min-height: 1.2em; }

button, input, select, textarea { font: inherit; color: inherit; }
button { border: 1px solid var(--line); background: var(--card); border-radius: 999px; padding: 8px 18px; cursor: pointer; }
button:hover { border-color: var(--accent); }
button.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
button.link { border: none; background: none; padding: 4px 0; color: var(--accent); }
button.danger { color: var(--error); }
button:disabled { opacity: .5; cursor: default; }
input, select, textarea { width: 100%; border: 1px solid var(--line); border-radius: 10px; padding: 9px 12px; background: var(--card); }
textarea { resize: vertical; font-family: ui-monospace, "SF Mono", Menlo, monospace; font-size: 14px; }
label { display: block; margin-bottom: 14px; font-weight: 600; }
label input, label select, label textarea { margin-top: 6px; font-weight: 400; }
label .muted { font-weight: 400; font-size: 13px; }

.topbar { display: flex; justify-content: space-between; align-items: center; padding: 14px 24px; border-bottom: 1px solid var(--line); background: var(--card); gap: 12px; flex-wrap: wrap; }
.brand { font-weight: 700; font-size: 18px; }
.brand span { color: var(--accent); }
.topbar-right { display: flex; gap: 16px; align-items: center; }
.topbar-right select { width: auto; margin: 0 4px; padding: 4px 8px; }

main { max-width: 1120px; margin: 0 auto; padding: 24px; }
.login { max-width: 460px; margin-top: 10vh; text-align: center; }
.login form { display: flex; gap: 10px; margin-top: 24px; }
.login input { font-size: 22px; letter-spacing: 6px; text-align: center; }

section { margin-bottom: 36px; }
.section-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: 14px; }
section > h2 { margin-bottom: 14px; }
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 14px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 16px; cursor: pointer; transition: border-color .15s; }
.card:hover { border-color: var(--accent); }
.card .title { font-weight: 600; font-size: 16px; }
.card .sub { color: var(--muted); font-size: 13px; margin-top: 4px; }
.card .badge { display: inline-block; font-size: 12px; color: var(--accent); background: var(--accent-soft); border-radius: 6px; padding: 0 8px; margin-top: 8px; }

.editor { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 420px); gap: 24px; align-items: start; }
.edit-pane, .preview-pane { background: var(--card); border: 1px solid var(--line); border-radius: 16px; padding: 20px; }
.back { margin-bottom: 12px; }
.actions { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }
.preview-pane { position: sticky; top: 16px; }
.preview-head { display: flex; justify-content: space-between; align-items: center; }
.chat { height: 380px; overflow-y: auto; margin: 12px 0; display: flex; flex-direction: column; gap: 10px; }
.bubble { max-width: 85%; padding: 9px 13px; border-radius: 14px; white-space: pre-wrap; }
.bubble.child { align-self: flex-end; background: var(--accent-soft); border-top-right-radius: 4px; }
.bubble.mumi { align-self: flex-start; background: var(--mumi); border-top-left-radius: 4px; }
.bubble.thinking { color: var(--muted); }
.chat-form { display: flex; gap: 8px; }

@media (max-width: 820px) {
  main { padding: 16px; }
  .editor { grid-template-columns: 1fr; }
  .preview-pane { position: static; }
  .chat { height: 300px; }
}