:root {
  --bg: #f6f7f9;
  --card: #ffffff;
  --text: #1c1f24;
  --muted: #6b7280;
  --line: #e5e7eb;
  --primary: #2563eb;
  --primary-soft: #eff4ff;
  --good: #059669;
  --bad: #dc2626;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111318;
    --card: #1a1d24;
    --text: #e8eaee;
    --muted: #9aa1ad;
    --line: #2b2f38;
    --primary: #60a5fa;
    --primary-soft: #1b2638;
    --good: #34d399;
    --bad: #f87171;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Malgun Gothic", "Noto Sans KR", sans-serif;
  line-height: 1.65;
  word-break: keep-all;
}
a { color: var(--primary); }
header, main, footer { max-width: 720px; margin: 0 auto; padding: 0 16px; }
header { padding-top: 20px; padding-bottom: 8px; }
header .logo { font-weight: 800; font-size: 1.15rem; text-decoration: none; color: var(--text); }
nav { display: flex; gap: 14px; flex-wrap: wrap; margin-top: 6px; font-size: .92rem; }
nav a { text-decoration: none; color: var(--muted); }
nav a.on { color: var(--primary); font-weight: 700; }
h1 { font-size: 1.5rem; margin: 18px 0 6px; }
h2 { font-size: 1.15rem; margin-top: 32px; }
.lead { color: var(--muted); margin-top: 0; }
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 18px;
  margin: 16px 0;
}
label { display: block; font-weight: 600; font-size: .95rem; margin: 12px 0 6px; }
label small { font-weight: 400; color: var(--muted); }
input[type=text], input[type=number], select {
  width: 100%;
  padding: 11px 12px;
  font-size: 1rem;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--bg);
  color: var(--text);
}
.row { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 8px; }
.chip {
  border: 1px solid var(--line);
  background: var(--bg);
  color: var(--text);
  border-radius: 999px;
  padding: 6px 12px;
  font-size: .88rem;
  cursor: pointer;
}
.chip:hover { border-color: var(--primary); }
.result { background: var(--primary-soft); border-color: transparent; }
.big { font-size: 1.7rem; font-weight: 800; margin: 4px 0; }
.big.good { color: var(--good); }
.big.bad { color: var(--bad); }
table { width: 100%; border-collapse: collapse; font-size: .93rem; }
td { padding: 7px 0; border-bottom: 1px solid var(--line); }
td:last-child { text-align: right; font-variant-numeric: tabular-nums; }
.note { font-size: .85rem; color: var(--muted); }
.warn { font-size: .9rem; color: var(--bad); margin-top: 8px; }
.grid { display: grid; gap: 12px; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }
.grid a.card { display: block; text-decoration: none; color: var(--text); margin: 0; }
.grid a.card:hover { border-color: var(--primary); }
.grid a.card b { display: block; font-size: 1.05rem; margin-bottom: 4px; }
/* 광고 자리. 애드센스 코드가 들어가기 전까지는 보이지 않는다 */
.ad-slot { margin: 16px 0; }
.ad-slot:empty { display: none; }
details { border-bottom: 1px solid var(--line); padding: 10px 0; }
summary { cursor: pointer; font-weight: 600; }
footer { color: var(--muted); font-size: .85rem; padding-top: 32px; padding-bottom: 40px; }
footer a { color: var(--muted); }