* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", sans-serif;
  color: #1a1f2b;
  line-height: 1.75;
  background: #fff;
}
.container { max-width: 960px; margin: 0 auto; padding: 0 24px; }

.site-header { border-bottom: 1px solid #e0e4ea; padding: 16px 0; }
.site-header .container { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px; }
.site-title { font-size: 1.15rem; font-weight: 700; color: #1a1f2b; text-decoration: none; }
.site-nav a { margin-left: 20px; color: #333a48; text-decoration: none; font-size: 0.95rem; }
.site-nav a:hover { text-decoration: underline; }

.breadcrumb { padding: 12px 0 0; font-size: 0.85rem; color: #5a6272; }
.breadcrumb ol { list-style: none; display: flex; gap: 6px; padding: 0; margin: 0; }
.breadcrumb li:not(:last-child)::after { content: "›"; margin-left: 6px; }
.breadcrumb a { color: #2b4c7e; text-decoration: none; }

.hero { background: #eef1f6; padding: 32px 0; }
.hero h1 { font-size: 1.7rem; margin: 0 0 10px; color: #1a1f2b; }
.hero p { margin: 0; color: #333a48; max-width: 640px; }

main.container { padding-top: 32px; padding-bottom: 48px; }
main h2 { font-size: 1.3rem; margin-top: 40px; }
main p { color: #333a48; max-width: 680px; }

.field-row { margin-bottom: 16px; max-width: 420px; }
.field-row label { display: block; font-weight: 600; margin-bottom: 6px; font-size: 0.9rem; }
.field-row select,
.field-row input[type="number"] {
  width: 100%;
  padding: 8px 10px;
  font-size: 1rem;
  border: 1px solid #ccc;
  border-radius: 6px;
}
button.btn-primary {
  background: #2b4c7e;
  color: #fff;
  border: none;
  padding: 10px 20px;
  font-size: 1rem;
  border-radius: 6px;
  cursor: pointer;
}
button.btn-primary:hover { background: #1e3a63; }

.result-box {
  border: 1px solid #d7dae0;
  border-radius: 10px;
  padding: 20px;
  margin-top: 16px;
  max-width: 520px;
}
.result-box .index-up { color: #b23c3c; font-weight: 700; }
.result-box .index-down { color: #2b6a4f; font-weight: 700; }

.disclaimer {
  background: #f6f7f9;
  border-left: 3px solid #9aa3b5;
  padding: 12px 16px;
  font-size: 0.9rem;
  color: #5a6272;
  margin-top: 20px;
  max-width: 680px;
}

table.pref-table { width: 100%; border-collapse: collapse; margin-top: 16px; font-size: 0.9rem; }
table.pref-table th, table.pref-table td { padding: 6px 10px; border-bottom: 1px solid #e5e7eb; text-align: right; }
table.pref-table th:first-child, table.pref-table td:first-child { text-align: left; }
table.pref-table tr.highlight { background: #eef1f6; font-weight: 700; }
.table-scroll { overflow-x: auto; }

.card-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 16px; margin: 24px 0; }
.card { display: block; border: 1px solid #d7dae0; border-radius: 10px; padding: 18px; text-decoration: none; color: inherit; }
.card:hover { border-color: #2b4c7e; }
.card h3 { margin: 0 0 8px; font-size: 1.05rem; }
.card p { margin: 0; font-size: 0.9rem; color: #5a6272; }

.site-footer { border-top: 1px solid #e0e4ea; padding: 20px 0; margin-top: 40px; }
.site-footer p { font-size: 0.85rem; color: #5a6272; margin: 0; }

@media (max-width: 640px) {
  .site-header .container { flex-direction: column; align-items: flex-start; }
  .site-nav a { margin-left: 0; margin-right: 16px; }
}