/* Root Variables for Chic Bookish Aesthetic */
:root {
  --text-dark: #2A3A29;
  --bg-color: #FDFBF7;
  --accent-gold: #C19A6B;
  --accent-gray: #E0DCD3;
  --transition: all 0.3s ease;
  --nav-bg: #FFFFFF;
}

body {
  margin: 0;
  padding: 0;
  font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
  color: var(--text-dark);
  background-color: var(--bg-color);
  line-height: 1.6;
}

/* Header */
.site-header {
  background-color: var(--nav-bg);
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
}

.logo a {
  text-decoration: none;
  font-size: 1.5rem;
  font-weight: bold;
  color: var(--text-dark);
}

/* Navigation - 2 Line Layout Rule */
.nav-menu {
  display: flex;
  list-style: none;
  gap: 1.5rem;
  align-items: center;
  flex-wrap: wrap;           /* 2行レイアウト対応 */
  max-width: 900px;          /* ナビゲーション全体の最大幅制限 */
  justify-content: center;   /* メニュー項目を中央配置 */
  margin: 0 auto;
  padding: 0 1rem 1rem;
}

.nav-item a {
  text-decoration: none;
  font-weight: 500;
  color: var(--text-dark);
  padding: 0.4rem 0.8rem;
  border-radius: 8px;
  transition: var(--transition);
  font-size: 0.9rem;         /* 適切なフォントサイズ */
  white-space: nowrap;       /* 項目内の改行を防止 */
}

.nav-item a:hover {
  background-color: var(--accent-gray);
  color: var(--accent-gold);
}

/* Hamburger */
.hamburger {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  flex-direction: column;
  gap: 5px;
}
.hamburger span {
  width: 25px;
  height: 3px;
  background-color: var(--text-dark);
  transition: var(--transition);
}

/* Hero Section */
.hero {
  position: relative;
  width: 100%;
  height: 60vh;
  min-height: 400px;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-image {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 1;
}

/* No blur on hero-image */
.hero-text {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 2rem;
  background: rgba(0,0,0,0.3);
  border-radius: 10px;
}

/* Text visibility rules */
.hero-text h2, .hero-text p {
  color: #FFFFFF;
  text-shadow: 2px 2px 8px rgba(0,0,0,0.8), -1px -1px 0 #000, 1px -1px 0 #000, -1px 1px 0 #000, 1px 1px 0 #000;
  margin: 0;
}
.hero-text h2 {
  font-size: 3rem;
  margin-bottom: 0.5rem;
}
.hero-text p {
  font-size: 1.2rem;
  font-weight: bold;
}

/* Container */
.container {
  max-width: 1200px;
  margin: 2rem auto;
  padding: 0 1rem;
}

/* Top Page Layout */
.overview, .news-section, .content-body {
  background: #FFF;
  padding: 2rem;
  margin-bottom: 2rem;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.news-list {
  list-style: none;
  padding: 0;
}
.news-list li {
  margin-bottom: 1rem;
  border-bottom: 1px solid var(--accent-gray);
  padding-bottom: 0.5rem;
}
.news-list .date {
  font-weight: bold;
  color: var(--accent-gold);
  margin-right: 1rem;
}
.news-list a {
  text-decoration: none;
  color: var(--text-dark);
}

/* Two Column Layout */
.two-column {
  display: flex;
  gap: 2rem;
  flex-wrap: nowrap;
}

.main-column {
  flex: 3;
  background: #FFF;
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.side-column {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 2rem;
  min-width: 300px;
}

.toc, .related-links, .side-banner {
  background: #FFF;
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.toc ul, .related-links ul {
  list-style: none;
  padding: 0;
}
.toc li, .related-links li {
  margin-bottom: 0.5rem;
}
.toc a, .related-links a {
  text-decoration: none;
  color: var(--accent-gold);
}

.banner-container {
  margin: 1.5rem 0;
  text-align: center;
}

.banner-container img {
  max-width: 100%;
  height: auto;
}

/* Footer */
.site-footer {
  background-color: var(--text-dark);
  color: #FFF;
  text-align: center;
  padding: 2rem;
  margin-top: 4rem;
}

.footer-links {
  margin-top: 1rem;
}

.footer-links a {
  color: var(--accent-gold);
  text-decoration: none;
  margin: 0 1rem;
}

/* Responsive */
@media (max-width: 768px) {
  .two-column {
    flex-direction: column;
  }
  .side-column {
    width: 100%;
    min-width: auto;
  }
  .hamburger {
    display: flex;
  }
  .main-nav {
    display: none;
    width: 100%;
    background-color: var(--nav-bg);
  }
  .main-nav.active {
    display: block;
  }
  .nav-menu {
    flex-direction: column;
    padding: 1rem;
  }
  .header-inner {
    flex-wrap: wrap;
  }
}