* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Hiragino Kaku Gothic ProN', 'ヒラギノ角ゴ ProN W3', sans-serif;
  line-height: 1.6;
  color: #333;
  background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
  min-height: 100vh;
}

/* ヘッダー */
header {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 1rem 0;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  position: sticky;
  top: 0;
  z-index: 100;
}

header nav {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

header .logo {
  font-size: 1.5rem;
  font-weight: bold;
  text-decoration: none;
  color: white;
  letter-spacing: 0.5px;
}

header nav a {
  color: white;
  text-decoration: none;
  margin-left: 2rem;
  transition: opacity 0.3s ease;
  font-size: 0.95rem;
}

header nav a:hover {
  opacity: 0.8;
}

/* メインコンテナ */
.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 3rem 2rem;
}

/* ページセクション */
section {
  background: white;
  border-radius: 12px;
  padding: 3rem;
  margin-bottom: 2rem;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  animation: slideIn 0.6s ease-out;
}

@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

h1 {
  font-size: 2.5rem;
  color: #667eea;
  margin-bottom: 1rem;
  border-bottom: 3px solid #764ba2;
  padding-bottom: 0.5rem;
}

h2 {
  font-size: 1.8rem;
  color: #667eea;
  margin-top: 2rem;
  margin-bottom: 1rem;
}

h3 {
  font-size: 1.3rem;
  color: #764ba2;
  margin-top: 1.5rem;
  margin-bottom: 0.8rem;
}

p {
  margin-bottom: 1rem;
  line-height: 1.8;
  text-align: justify;
}

ul, ol {
  margin-left: 2rem;
  margin-bottom: 1rem;
}

li {
  margin-bottom: 0.8rem;
  line-height: 1.8;
}

/* ホームページ用スタイル */
.hero {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  text-align: center;
  padding: 4rem 2rem;
  border-radius: 12px;
  margin-bottom: 2rem;
}

.hero h1 {
  color: white;
  border-bottom: none;
  font-size: 3rem;
  margin-bottom: 1rem;
}

.hero p {
  font-size: 1.1rem;
  margin-bottom: 0;
}

.links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.link-card {
  background: linear-gradient(135deg, #667eea15 0%, #764ba215 100%);
  padding: 2rem;
  border-radius: 12px;
  border-left: 4px solid #667eea;
  text-decoration: none;
  color: inherit;
  transition: all 0.3s ease;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.link-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 20px rgba(102, 126, 234, 0.2);
  border-left-color: #764ba2;
}

.link-card h3 {
  color: #667eea;
  margin-top: 0;
}

/* テーブル */
table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1rem;
}

th, td {
  border: 1px solid #ddd;
  padding: 0.8rem;
  text-align: left;
}

th {
  background-color: #667eea;
  color: white;
}

tr:nth-child(even) {
  background-color: #f9f9f9;
}

/* フッター */
footer {
  background: #333;
  color: white;
  text-align: center;
  padding: 2rem;
  margin-top: 3rem;
}

footer p {
  margin-bottom: 0.5rem;
  text-align: center;
}

footer a {
  color: #667eea;
  text-decoration: none;
}

footer a:hover {
  text-decoration: underline;
}

/* レスポンシブ */
@media (max-width: 768px) {
  h1 {
    font-size: 1.8rem;
  }

  h2 {
    font-size: 1.3rem;
  }

  section {
    padding: 1.5rem;
  }

  .container {
    padding: 1.5rem;
  }

  header nav {
    padding: 0 1rem;
  }

  header nav a {
    margin-left: 1rem;
    font-size: 0.85rem;
  }

  .hero h1 {
    font-size: 2rem;
  }

  .links {
    grid-template-columns: 1fr;
  }
}