/* 説明ページ（howto.html / privacy.html）共通のスタイル。index.html とは別に持つ */
:root {
  --ink: #0f1b3d;
  --ink-2: #6b7385;
  --paper: #fafafa;
  --field: #f1f3f8;
  --line: #e3e7f0;
  --navy-2: #1b3a82;
  --gold: #e9b200;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: "Hiragino Sans", "Noto Sans JP", system-ui, sans-serif;
  line-height: 1.85;
  padding: 0 20px 64px;
}
.wrap { max-width: 640px; margin: 0 auto; }
.top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 0 8px;
}
.brand { display: flex; align-items: center; gap: 10px; color: var(--ink); text-decoration: none; }
.brand img { width: 36px; height: 36px; }
.brand span { font-size: 20px; font-weight: 800; letter-spacing: -0.03em; }
.back { font-size: 13px; color: var(--navy-2); text-decoration: none; }
.back:hover { text-decoration: underline; }
.crumb { display: flex; flex-wrap: wrap; gap: 6px; align-items: center; margin-top: 18px; font-size: 12px; color: var(--ink-2); }
.crumb a { color: var(--navy-2); text-decoration: none; }
.crumb a:hover { text-decoration: underline; }
.crumb + h1 { margin-top: 8px; }
h1 { font-size: 26px; margin: 32px 0 6px; letter-spacing: -0.01em; line-height: 1.4; }
.updated { font-size: 12px; color: var(--ink-2); margin: 0 0 8px; }
h2 {
  font-size: 18px;
  margin: 44px 0 8px;
  padding-left: 12px;
  border-left: 4px solid var(--gold);
  line-height: 1.5;
}
p, li { font-size: 15px; }
p { margin: 10px 0; }
ul, ol { padding-left: 22px; margin: 10px 0; }
li { margin: 4px 0; }
a { color: var(--navy-2); }
.formula {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 16px 18px;
  font-size: 15px;
  font-variant-numeric: tabular-nums;
  margin: 14px 0;
}
table {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
  font-size: 14px;
  font-variant-numeric: tabular-nums;
  margin: 14px 0;
}
th, td { padding: 10px 14px; text-align: right; border-bottom: 1px solid var(--line); }
th:first-child, td:first-child { text-align: left; }
th { background: var(--field); font-weight: 700; font-size: 13px; }
tr:last-child td { border-bottom: 0; }
.penalty { color: #c0262d; font-weight: 700; text-decoration: underline; text-decoration-thickness: 2px; text-underline-offset: 3px; }
.note {
  font-size: 13px;
  color: var(--ink-2);
  background: var(--field);
  border-radius: 12px;
  padding: 12px 16px;
}
footer {
  margin-top: 56px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
  font-size: 12px;
  color: var(--ink-2);
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}
footer a { color: var(--ink-2); }

/* 広告（Google AdSense）。文章の途中に 1 つ。操作部品から離し、広告と分かるラベルを付ける */
.ad-block {
  margin: 40px 0;
  text-align: center;
}
.ad-label {
  display: block;
  margin-bottom: 6px;
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--ink-2);
}

/* 広告が入らなかったとき（承認前・在庫なし）は、空白とラベルを畳む */
.adsbygoogle[data-ad-status="unfilled"] { display: none !important; }
.ad-block:has(.adsbygoogle[data-ad-status="unfilled"]) { display: none; }

/* 記事の最後の、アプリへの誘導 */
.cta { display: block; text-align: center; margin: 24px 0; padding: 16px; border-radius: 18px; color: #fff; font-weight: 700; text-decoration: none; background: linear-gradient(135deg, #0f1b3d 0%, #1b3a82 55%, #e9b200 100%); }
.copy { margin: 4px 0 0; text-align: center; font-size: 11px; color: #8a93a8; }

.tool-list { list-style: none; margin: 0; padding: 0; }
.tool-list li { padding: 10px 0; border-bottom: 1px solid var(--line, #e3e7f0); }
.tool-list a { font-weight: 700; color: var(--navy-2); text-decoration: none; }
.tool-list a:hover { text-decoration: underline; }
.tool-list span { display: block; font-size: 13px; color: var(--ink-2); line-height: 1.6; }
.lang { display: flex; justify-content: center; gap: 4px; margin: 10px 0 4px; font-size: 12px; }
.lang a { color: var(--ink-2); text-decoration: none; padding: 3px 10px; border-radius: 999px; }
.lang a:hover { text-decoration: underline; }
.lang a[aria-current] { color: var(--ink); font-weight: 700; background: var(--field); }