/* 共通スタイル */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary-color: #007AFF;
  --bg-color: #ffffff;
  --text-color: #000000;
  --secondary-text: #666666;
  --border-color: #e5e5e7;
  --header-bg: #f2f2f7;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg-color: #000000;
    --text-color: #ffffff;
    --secondary-text: #8e8e93;
    --border-color: #38383a;
    --header-bg: #1c1c1e;
  }
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  line-height: 1.6;
  padding: 0;
  margin: 0;
}

.container {
  max-width: 800px;
  margin: 0 auto;
  padding: 20px;
}

header {
  background-color: var(--header-bg);
  border-bottom: 1px solid var(--border-color);
  padding: 20px 0;
  margin-bottom: 30px;
}

h1 {
  font-size: 28px;
  font-weight: 600;
  margin-bottom: 10px;
  color: var(--text-color);
}

h2 {
  font-size: 22px;
  font-weight: 600;
  margin-top: 30px;
  margin-bottom: 15px;
  color: var(--text-color);
}

h3 {
  font-size: 18px;
  font-weight: 600;
  margin-top: 20px;
  margin-bottom: 10px;
  color: var(--text-color);
}

p {
  margin-bottom: 15px;
  color: var(--text-color);
}

ul, ol {
  margin-left: 20px;
  margin-bottom: 15px;
}

li {
  margin-bottom: 8px;
  color: var(--text-color);
}

a {
  color: var(--primary-color);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.last-updated {
  color: var(--secondary-text);
  font-size: 14px;
  margin-bottom: 20px;
}

.section {
  margin-bottom: 30px;
}

.back-link {
  display: inline-block;
  margin-bottom: 20px;
  color: var(--primary-color);
  font-size: 16px;
}

.back-link:hover {
  text-decoration: underline;
}

.nav-links {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  margin-top: 20px;
}

.nav-link {
  background-color: var(--primary-color);
  color: white;
  padding: 12px 24px;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 500;
  display: inline-block;
  transition: opacity 0.2s;
}

.nav-link:hover {
  opacity: 0.8;
  text-decoration: none;
}

.support-contact {
  background-color: var(--header-bg);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 20px;
  margin-top: 30px;
}

.support-contact h3 {
  margin-top: 0;
}

.email-link {
  color: var(--primary-color);
  font-size: 18px;
  font-weight: 500;
}

/* モバイル対応 */
@media (max-width: 768px) {
  .container {
    padding: 15px;
  }

  h1 {
    font-size: 24px;
  }

  h2 {
    font-size: 20px;
  }

  h3 {
    font-size: 16px;
  }

  .nav-links {
    flex-direction: column;
    gap: 10px;
  }

  .nav-link {
    text-align: center;
  }
}