:root {
  --bg: #fafafa;
  --fg: #1f2328;
  --muted: #667085;
  --card: #fff;
  --border: #d0d5dd;
  --accent: #e5322d;
  --accent-soft: #fdecec;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14161a;
    --fg: #e8eaed;
    --muted: #9aa0a6;
    --card: #1e2127;
    --border: #3a3f47;
    --accent: #ff6b66;
    --accent-soft: #2c1b1b;
  }
}
* { box-sizing: border-box; }
body {
  font-family: system-ui, -apple-system, "Hiragino Sans", "Yu Gothic UI", sans-serif;
  background: var(--bg);
  color: var(--fg);
  margin: 0;
  padding: 1.5rem 1rem 3rem;
  line-height: 1.6;
}
main { max-width: 32rem; margin: 0 auto; }
h1 { font-size: 1.4rem; margin: 0 0 .25rem; }
.lead { color: var(--muted); margin: 0 0 1.25rem; font-size: .95rem; }
form { display: grid; gap: 1rem; }
label { display: grid; gap: .3rem; font-weight: 600; font-size: .95rem; }
input, select {
  font: inherit;
  padding: .6rem .7rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card);
  color: var(--fg);
  width: 100%;
}
input:focus, select:focus { outline: 2px solid var(--accent); outline-offset: 1px; }
.error { color: var(--accent); margin: 1rem 0 0; }
.result {
  margin-top: 1.5rem;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.25rem;
}
.price {
  background: var(--accent-soft);
  border-radius: 10px;
  padding: .9rem 1rem;
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1rem;
}
.price .label { font-weight: 600; }
.price .value { font-size: 1.9rem; font-weight: 700; color: var(--accent); }
dl { margin: 1rem 0 0; }
dl div {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: .45rem 0;
  border-bottom: 1px solid var(--border);
}
dl div:last-child { border-bottom: 0; }
dt { color: var(--muted); font-size: .92rem; }
dd { margin: 0; font-variant-numeric: tabular-nums; }
.strong dt, .strong dd { color: var(--fg); font-weight: 700; }
.note { color: var(--muted); font-size: .8rem; margin: 1rem 0 0; }
[hidden] { display: none !important; }