:root {
  --bg: #f6f7fb;
  --panel: #ffffff;
  --panel-soft: #f0f3f8;
  --text: #1f2937;
  --muted: #6b7280;
  --line: #e5e7eb;
  --primary: #2563eb;
  --primary-soft: #dbeafe;
  --danger: #dc2626;
  --shadow: 0 20px 50px rgba(15, 23, 42, 0.08);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans JP", sans-serif;
  line-height: 1.75;
}

a {
  color: var(--primary);
}

img {
  max-width: 100%;
  display: block;
}

.seo-page {
  max-width: 100%;
  overflow-x: hidden;
}

/* ── ヘッダー ─────────────────────────────────────────────────────────── */

.seo-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 14px 20px;
  background: var(--panel);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 10;
}

.seo-header-back {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 8px 12px;
  border-radius: 10px;
  border: 1px solid var(--line);
  background: var(--panel);
  color: var(--text);
  font-size: 13px;
  font-weight: 700;
  text-decoration: none;
  white-space: nowrap;
}

.seo-header-back:hover {
  background: var(--panel-soft);
}

.seo-header-logo {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 16px;
  font-weight: 900;
  color: var(--text);
  text-decoration: none;
}

.seo-header-logo img {
  width: 28px;
  height: 28px;
  border-radius: 8px;
}

.seo-header-cta {
  display: inline-flex;
  align-items: center;
  padding: 8px 16px;
  border-radius: 10px;
  background: var(--primary);
  color: #fff;
  font-size: 13px;
  font-weight: 800;
  text-decoration: none;
  white-space: nowrap;
}

.seo-header-cta:hover {
  filter: brightness(1.05);
}

/* ── 本文レイアウト ───────────────────────────────────────────────────── */

.seo-main {
  max-width: 760px;
  margin: 0 auto;
  padding: 32px 20px 8px;
}

.seo-main h1 {
  font-size: 26px;
  font-weight: 900;
  line-height: 1.4;
  margin: 0 0 12px;
  color: var(--text);
}

.seo-main h2 {
  font-size: 19px;
  font-weight: 800;
  margin: 36px 0 12px;
  color: var(--text);
  padding-top: 4px;
}

.seo-main h3 {
  font-size: 16px;
  font-weight: 800;
  margin: 20px 0 8px;
  color: var(--text);
}

.seo-main p {
  margin: 0 0 14px;
  color: var(--text);
}

.seo-main ul,
.seo-main ol {
  margin: 0 0 14px;
  padding-left: 1.4em;
}

.seo-main li {
  margin-bottom: 6px;
}

.seo-lead {
  font-size: 15px;
  color: var(--muted);
  margin-bottom: 20px;
}

.seo-eyebrow {
  display: inline-block;
  font-size: 12px;
  font-weight: 800;
  color: var(--primary);
  background: var(--primary-soft);
  padding: 4px 10px;
  border-radius: 999px;
  margin-bottom: 12px;
}

.seo-updated {
  font-size: 12px;
  color: var(--muted);
  margin: -8px 0 20px;
}

/* ── ヒーロー（ランディング用） ───────────────────────────────────────── */

.seo-hero {
  max-width: 760px;
  margin: 0 auto;
  padding: 40px 20px 12px;
  text-align: center;
}

.seo-hero h1 {
  font-size: 30px;
}

.seo-hero-lead {
  font-size: 16px;
  color: var(--muted);
  max-width: 560px;
  margin: 0 auto 24px;
}

.seo-hero-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 16px 32px;
  border-radius: 14px;
  background: var(--primary);
  color: #fff;
  font-size: 16px;
  font-weight: 900;
  text-decoration: none;
  box-shadow: var(--shadow);
}

.seo-hero-cta:hover {
  filter: brightness(1.05);
}

.seo-hero-note {
  margin-top: 10px;
  font-size: 12px;
  color: var(--muted);
}

/* ── カード / グリッド ────────────────────────────────────────────────── */

.seo-card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 14px;
  margin: 20px 0 28px;
}

.seo-card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 18px;
}

.seo-card-icon {
  font-size: 24px;
  margin-bottom: 8px;
}

.seo-card h3 {
  margin: 0 0 6px;
  font-size: 15px;
}

.seo-card p {
  margin: 0;
  font-size: 13px;
  color: var(--muted);
}

.seo-steps {
  counter-reset: seo-step;
  list-style: none;
  margin: 20px 0 28px;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.seo-steps li {
  counter-increment: seo-step;
  position: relative;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 16px 16px 16px 56px;
  margin: 0;
}

.seo-steps li::before {
  content: counter(seo-step);
  position: absolute;
  left: 16px;
  top: 16px;
  width: 26px;
  height: 26px;
  border-radius: 999px;
  background: var(--primary);
  color: #fff;
  font-size: 13px;
  font-weight: 900;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.seo-steps strong {
  display: block;
  margin-bottom: 4px;
  font-size: 14px;
}

.seo-steps span {
  font-size: 13px;
  color: var(--muted);
}

/* ── FAQ ──────────────────────────────────────────────────────────────── */

.seo-faq-list {
  list-style: none;
  margin: 20px 0 28px;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.seo-faq-item {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 16px 18px;
}

.seo-faq-q {
  font-weight: 800;
  font-size: 14px;
  margin: 0 0 6px;
  display: flex;
  gap: 8px;
}

.seo-faq-q::before {
  content: "Q";
  flex-shrink: 0;
  color: var(--primary);
}

.seo-faq-a {
  font-size: 13px;
  color: var(--muted);
  margin: 0;
  display: flex;
  gap: 8px;
}

.seo-faq-a::before {
  content: "A";
  flex-shrink: 0;
  color: var(--muted);
  font-weight: 800;
}

/* ── CTAボックス ──────────────────────────────────────────────────────── */

.seo-cta-box {
  max-width: 760px;
  margin: 32px auto;
  padding: 28px 24px;
  border-radius: 20px;
  background: linear-gradient(135deg, var(--primary-soft), #fff);
  border: 1px solid var(--primary-soft);
  text-align: center;
}

.seo-cta-box p {
  margin: 0 0 14px;
  font-size: 14px;
  color: var(--text);
  font-weight: 700;
}

.seo-cta-box a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: 12px;
  background: var(--primary);
  color: #fff;
  font-size: 15px;
  font-weight: 900;
  text-decoration: none;
}

.seo-cta-box a:hover {
  filter: brightness(1.05);
}

/* ── 関連リンクnav ────────────────────────────────────────────────────── */

.seo-related {
  max-width: 760px;
  margin: 0 auto;
  padding: 8px 20px 40px;
}

.seo-related h2 {
  font-size: 14px;
  color: var(--muted);
  font-weight: 800;
  margin: 0 0 12px;
}

.seo-related-groups {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
}

.seo-related-group h3 {
  font-size: 12px;
  color: var(--muted);
  font-weight: 800;
  margin: 0 0 8px;
}

.seo-related-group ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.seo-related-group a {
  font-size: 13px;
  text-decoration: none;
  color: var(--text);
  border-bottom: 1px dashed var(--line);
  padding-bottom: 2px;
  display: inline-block;
}

.seo-related-group a:hover {
  color: var(--primary);
  border-color: var(--primary);
}

/* ── フッター ─────────────────────────────────────────────────────────── */

.seo-footer {
  border-top: 1px solid var(--line);
  background: var(--panel);
  padding: 24px 20px 32px;
}

.seo-footer-inner {
  max-width: 760px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.seo-footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.seo-footer-links a {
  font-size: 12px;
  color: var(--muted);
  text-decoration: none;
}

.seo-footer-links a:hover {
  color: var(--primary);
}

.seo-footer-meta {
  font-size: 12px;
  color: var(--muted);
}

/* ── 記事（ブログ・キーワードページ）用の見た目調整 ──────────────────── */

.seo-article-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 18px;
}

.seo-tag {
  font-size: 11px;
  font-weight: 800;
  color: var(--primary);
  background: var(--primary-soft);
  padding: 3px 10px;
  border-radius: 999px;
}

/* ── レスポンシブ ─────────────────────────────────────────────────────── */

@media (max-width: 480px) {
  .seo-header {
    padding: 12px 14px;
  }

  .seo-header-logo span {
    display: none;
  }

  .seo-main,
  .seo-hero,
  .seo-related {
    padding-left: 16px;
    padding-right: 16px;
  }

  .seo-main h1,
  .seo-hero h1 {
    font-size: 22px;
  }

  .seo-cta-box {
    margin: 24px 16px;
    padding: 22px 18px;
  }
}