:root {
  --bg: #fbfaf7;
  --fg: #1f1d1a;
  --muted: #6b665e;
  --line: #ddd8cf;
  --accent: #2f6f62;
  --panel: #ffffff;
  --rt: #4a5b8c;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #161514;
    --fg: #ece8e1;
    --muted: #a39d93;
    --line: #3a3733;
    --accent: #7cc3b2;
    --panel: #1f1e1c;
    --rt: #a9b8e8;
    color-scheme: dark;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0 auto;
  max-width: 52rem;
  padding: 1.5rem 1rem 3rem;
  background: var(--bg);
  color: var(--fg);
  font-family: system-ui, "Hiragino Sans", "Noto Sans JP", "Yu Gothic UI", sans-serif;
  line-height: 1.7;
}
h1 { font-size: 1.6rem; margin: 0 0 .5rem; }
.lead { margin: 0 0 .25rem; }
.en { margin: 0 0 1.5rem; color: var(--muted); font-size: .9rem; }
.field-label { font-weight: 600; display: block; margin-bottom: .25rem; }
textarea {
  width: 100%;
  padding: .75rem;
  border: 1px solid var(--line);
  border-radius: .5rem;
  background: var(--panel);
  color: var(--fg);
  font: inherit;
  resize: vertical;
}
.options { margin: .75rem 0; display: grid; gap: .5rem; }
fieldset { border: 0; padding: 0; margin: 0; display: flex; gap: 1rem; flex-wrap: wrap; align-items: center; }
legend { float: left; margin-right: .5rem; font-weight: 600; }
.status { color: var(--muted); margin: .5rem 0 0; min-height: 1.7em; }
.status.error { color: #c0392b; }
@media (prefers-color-scheme: dark) {
  .status.error { color: #ff8a7a; } /* 暗い背景でも読める濃さ */
}
.stats { margin: 0 0 .75rem; color: var(--muted); font-size: .9rem; min-height: 1.5em; }
.tabs { display: flex; gap: .25rem; border-bottom: 1px solid var(--line); }
.tabs button {
  border: 1px solid transparent;
  border-bottom: 0;
  background: none;
  color: var(--muted);
  padding: .5rem .9rem;
  border-radius: .5rem .5rem 0 0;
  font: inherit;
  cursor: pointer;
}
.tabs button[aria-selected="true"] { color: var(--fg); border-color: var(--line); background: var(--panel); font-weight: 600; }
[role="tabpanel"] { padding-top: .75rem; }
.view {
  padding: 1rem;
  border: 1px solid var(--line);
  border-radius: .5rem;
  background: var(--panel);
  white-space: pre-wrap;
  line-height: 2.2;
  overflow-wrap: anywhere;
}
rt { color: var(--rt); font-size: .55em; }
.hint { margin: 0 0 .5rem; color: var(--muted); font-size: .9rem; }
.copy {
  margin-top: .5rem;
  padding: .45rem 1rem;
  border: 0;
  border-radius: .5rem;
  background: var(--accent);
  color: var(--bg);
  font: inherit;
  cursor: pointer;
}
.copied { color: var(--accent); min-height: 1.7em; margin: .25rem 0 0; }
.reload { margin-left: .5rem; font: inherit; }
footer { margin-top: 2.5rem; padding-top: 1rem; border-top: 1px solid var(--line); color: var(--muted); font-size: .85rem; }
footer a { color: var(--accent); }