:root {
      --bg-soft: #f5f7fb;
      --primary: #4fb3d9;
      --primary-strong: #3da0c7;
      --accent: #7ac7b8;
      --text-main: #1f2d3d;
      --text-sub: #516274;
      --border-soft: #e3e8f0;
      --danger: #e55959;
    }

    * {
      box-sizing: border-box;
    }

    body {
      margin: 0;
      padding: 16px;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
      background: var(--bg-soft);
      color: var(--text-main);
      line-height: 1.7;
      min-height: 100vh;
      display: flex;
      flex-direction: column;
      align-items: center;
    }

    .card {
      background: #fff;
      width: 100%;
      max-width: 480px;
      padding: 22px 22px 20px;
      border-radius: 16px;
      box-shadow: 0 14px 30px rgba(31, 45, 61, 0.10);
      margin-bottom: 20px;
    }

    .logo {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 18px;
      color: var(--primary);
      margin-bottom: 4px;
    }

    .site-name {
      font-size: 22px;
      font-weight: 700;
      margin: 4px 0 6px;
      color: var(--text-main);
    }

    .tagline {
      font-size: 14px;
      color: var(--text-sub);
      margin: 0 0 18px;
    }

    h1 {
      font-size: 22px;
      margin: 10px 0 12px;
      line-height: 1.5;
      color: var(--text-main);
    }

    .lead {
      font-size: 15px;
      color: var(--text-sub);
      margin: 0 0 22px;
      white-space: pre-line;
    }

    h2 {
      font-size: 17px;
      margin: 0 0 10px;
      color: var(--text-main);
    }

    ul {
      margin: 0 0 22px 18px;
      padding: 0;
      color: var(--text-sub);
      font-size: 15px;
      display: grid;
      gap: 8px;
    }

    .primary-btn,
    .secondary-btn {
      display: inline-flex;
      justify-content: center;
      align-items: center;
      width: 100%;
      padding: 14px 16px;
      border-radius: 12px;
      font-weight: 700;
      font-size: 16px;
      text-decoration: none;
      border: none;
      cursor: pointer;
      transition: transform 0.1s ease, box-shadow 0.2s ease, filter 0.2s ease;
      margin-bottom: 10px;
    }

    .primary-btn {
      background: linear-gradient(135deg, var(--primary), var(--accent));
      color: #fff;
      box-shadow: 0 10px 20px rgba(79, 179, 217, 0.25);
    }

    .primary-btn:hover {
      filter: brightness(1.05);
      box-shadow: 0 12px 22px rgba(79, 179, 217, 0.28);
    }

    .primary-btn:active,
    .secondary-btn:active {
      transform: translateY(1px);
      box-shadow: 0 8px 16px rgba(79, 179, 217, 0.20);
    }

    .secondary-btn {
      background: #ffffff;
      color: var(--primary-strong);
      border: 1px solid var(--border-soft);
    }

    .btn-note {
      font-size: 13px;
      color: var(--text-sub);
      margin: 0 0 16px;
    }

    .note {
      font-size: 12px;
      color: var(--text-sub);
      background: #f7f9fd;
      border: 1px solid var(--border-soft);
      border-radius: 10px;
      padding: 12px;
      line-height: 1.6;
    }

    footer {
      width: 100%;
      text-align: center;
      margin: 18px 0 12px;
      color: #718097;
      font-size: 13px;
    }

    /* かんたんチェック用フォーム */
    .section-title {
      font-size: 18px;
      font-weight: 700;
      margin: 4px 0 10px;
    }

    .step-label {
      font-size: 13px;
      font-weight: 600;
      letter-spacing: 0.03em;
      text-transform: uppercase;
      color: var(--primary-strong);
      margin-bottom: 4px;
    }

    .field {
      margin-bottom: 18px;
    }

    .field label {
      display: block;
      font-size: 14px;
      font-weight: 600;
      margin-bottom: 4px;
    }

    .field small {
      display: block;
      font-size: 12px;
      color: var(--text-sub);
      margin-top: 2px;
    }

    .radio-group {
      display: grid;
      gap: 6px;
      margin-top: 6px;
    }

    .radio-item {
      display: flex;
      align-items: center;
      gap: 6px;
      font-size: 14px;
      color: var(--text-main);
    }

    input[type="number"],
    input[type="text"] {
      width: 100%;
      padding: 10px 11px;
      font-size: 15px;
      border-radius: 10px;
      border: 1px solid var(--border-soft);
      outline: none;
      transition: border-color 0.15s ease, box-shadow 0.15s ease;
    }

    input[type="number"]:focus,
    input[type="text"]:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 1px rgba(79, 179, 217, 0.2);
    }

    .inline-suffix {
      display: flex;
      align-items: center;
      gap: 6px;
    }

    .inline-suffix span {
      font-size: 14px;
      color: var(--text-sub);
    }

    .helper {
      font-size: 12px;
      color: var(--text-sub);
      margin: 0 0 16px;
    }

    .error {
      font-size: 12px;
      color: var(--danger);
      margin-top: 4px;
    }

    /* 結果表示 */
    .result-card {
      background: #f7f9fd;
      border-radius: 14px;
      border: 1px solid var(--border-soft);
      padding: 14px 14px 12px;
      margin-top: 14px;
      display: none;
    }

    .result-label {
      font-size: 13px;
      font-weight: 600;
      color: var(--primary-strong);
      margin-bottom: 4px;
      text-transform: uppercase;
      letter-spacing: 0.04em;
    }

    .result-main {
      font-size: 18px;
      font-weight: 700;
      margin: 4px 0 8px;
    }

    .badge {
      display: inline-block;
      padding: 3px 8px;
      border-radius: 999px;
      font-size: 11px;
      font-weight: 600;
      margin-left: 6px;
      background: #e2f3ff;
      color: var(--primary-strong);
    }

    .result-summary {
      font-size: 14px;
      color: var(--text-sub);
      margin: 0 0 8px;
    }

    .result-list {
      margin: 6px 0 8px;
      padding-left: 18px;
      font-size: 13px;
      color: var(--text-sub);
    }

    .result-meta {
      font-size: 12px;
      color: var(--text-sub);
      margin: 4px 0 0;
    }

    /* 都道府県リスト */
    .prefecture-title {
      font-size: 18px;
      font-weight: 700;
      margin: 6px 0 12px;
      color: var(--text-main);
    }

    .prefecture-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
      gap: 10px 12px;
      margin-top: 10px;
      padding: 0;
      list-style: none;
    }

    .prefecture-grid li {
      margin: 0;
    }

    .prefecture-link {
      display: block;
      padding: 10px 12px;
      border-radius: 12px;
      text-decoration: none;
      background: #f7f9fd;
      color: var(--text-main);
      border: 1px solid var(--border-soft);
      font-size: 14px;
      font-weight: 600;
      transition: background 0.15s ease, transform 0.1s ease, box-shadow 0.2s ease;
    }

    .prefecture-link:hover {
      background: #eef6fb;
      box-shadow: 0 10px 18px rgba(31, 45, 61, 0.08);
    }

    .prefecture-link:active {
      transform: translateY(1px);
      box-shadow: 0 6px 12px rgba(31, 45, 61, 0.08);
    }

    /* 市区町村リスト */
    .city-section {
      margin-top: 6px;
    }

    .pref-accordion {
      display: grid;
      gap: 10px;
    }

    .pref-toggle {
      width: 100%;
      text-align: left;
      padding: 12px 12px;
      border: 1px solid var(--border-soft);
      border-radius: 12px;
      background: #ffffff;
      color: var(--text-main);
      font-weight: 700;
      font-size: 15px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      transition: border-color 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
    }

    .pref-toggle:hover,
    .pref-toggle:focus {
      outline: none;
      border-color: var(--primary);
      box-shadow: 0 0 0 1px rgba(79, 179, 217, 0.14);
      background: #f9fcff;
    }

    .pref-toggle span {
      font-size: 13px;
      color: var(--text-sub);
      font-weight: 600;
    }

    .city-list {
      margin: 6px 0 0 18px;
      padding: 0;
      color: var(--text-sub);
      font-size: 14px;
      display: grid;
      gap: 6px;
      list-style: disc;
    }

    .city-link {
      color: var(--text-main);
      text-decoration: none;
      font-weight: 600;
    }

    .city-link:hover,
    .city-link:focus {
      color: var(--primary-strong);
      text-decoration: underline;
      outline: none;
    }

    @media (min-width: 768px) {
      body {
        padding: 32px;
      }

      .card {
        padding: 28px 30px 26px;
      }
    }
 /* 都道府県ボタン全体のレイアウト */
#accordion-container {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 12px 16px;
  padding: 12px 0;
  margin-top: 16px;
  background: #ffffff;
  border: 1px solid var(--border-soft);
  border-radius: 16px;
  box-shadow: 0 6px 18px rgba(31, 45, 61, 0.06);
}


/* 都道府県ボタンのデザイン */
.pref-button {
  background-color: #f0f0f5;
  border: 1px solid #ccc;
  border-radius: 8px;
  padding: 10px 12px;
  font-size: 1rem;
  cursor: pointer;
  transition: background-color 0.2s ease, box-shadow 0.2s ease;
  box-shadow: 0 1px 2px rgba(0,0,0,0.05);
  text-align: center;
}

/* ホバー時や展開時の視覚フィードバック */

.pref-button.active {
  background-color: #cce5ff !important;
  border-color: #66aaff !important;
  color: #1f2d3d !important; /* 任意：強調したい場合はここも変更 */
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}
.pref-button.active:focus {
  background-color: #cce5ff;
}

/* 市区町村リスト表示部 */
.city-list {
  grid-column: 1 / -1;
  padding: 8px 16px;
  background-color: #fafafa;
  border-left: 4px solid #d0d0d0;
  border-radius: 4px;
  margin-bottom: 12px;
}

.city-list ul {
  padding-left: 1.2em;
  margin: 0;
  font-size: 0.95rem;
}

.city-list li {
  margin: 2px 0;
}