:root {
  --primary-color: #141e3a;
  --secondary-color: #c9c67d;
  --accent-color: #2c7af5;
  --text-color: #333333;
  --light-text-color: #666666;
  --light-bg-color: #f8f9fa;
  --border-color: #dddddd;
  --footer-color: #141e3a;
  --header-height: 80px;
  --container-width: 1200px;
  --sidebar-width: 280px;
}

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

html {
  font-size: 62.5%;
  scroll-behavior: smooth;
}

body {
  font-family: 'Helvetica Neue', Arial, 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;
  font-size: 1.6rem;
  line-height: 1.6;
  color: var(--text-color);
  background-color: #ffffff;
}

a {
  color: var(--accent-color);
  text-decoration: none;
  transition: color 0.3s ease;
}

a:hover {
  text-decoration: underline;
}

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

.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.header {
  background-color: #fff;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: var(--header-height);
}

.logo {
  display: flex;
  align-items: center;
}

.logo img {
  height: 60px;
}

/* Navigation */
.nav {
  display: flex;
}

.nav-list {
  display: flex;
  list-style: none;
}

.nav-item {
  position: relative;
  margin-left: 10px;
}

.nav-link {
  display: block;
  padding: 10px 15px;
  color: var(--text-color);
  font-weight: 500;
  transition: all 0.3s ease;
}

.nav-link:hover {
  color: var(--accent-color);
  text-decoration: none;
}

.nav-item.active .nav-link {
  color: var(--accent-color);
  font-weight: bold;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 2.4rem;
  cursor: pointer;
  color: var(--text-color);
}

/* Main Content */
.main {
  padding: 40px 0;
  min-height: calc(100vh - var(--header-height) - 100px);
}

.content-wrapper {
  display: flex;
  gap: 40px;
}

.content {
  flex: 1;
}

.sidebar {
  width: var(--sidebar-width);
}

/* Page Header */
.page-header {
  margin-bottom: 30px;
  padding-bottom: 15px;
  border-bottom: 2px solid var(--primary-color);
}

.page-title {
  font-size: 2.8rem;
  color: var(--primary-color);
  font-weight: bold;
}

/* Breadcrumb */
.breadcrumb {
  display: flex;
  list-style: none;
  margin-bottom: 20px;
  font-size: 1.4rem;
  color: var(--light-text-color);
}

.breadcrumb-item:not(:last-child)::after {
  content: "›";
  margin: 0 10px;
}

/* Cards */
.card {
  background-color: #fff;
  border-radius: 8px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
  overflow: hidden;
  margin-bottom: 30px;
}

.card-header {
  padding: 15px 20px;
  background-color: var(--primary-color);
  color: #fff;
}

.card-title {
  font-size: 1.8rem;
  margin: 0;
}

.card-body {
  padding: 20px;
}

/* Sidebar */
.sidebar-section {
  margin-bottom: 30px;
}

.sidebar-title {
  font-size: 1.8rem;
  margin-bottom: 15px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--primary-color);
  color: var(--primary-color);
}

.sidebar-list {
  list-style: none;
}

.sidebar-item {
  margin-bottom: 10px;
}

.sidebar-link {
  display: block;
  padding: 10px 15px;
  background-color: var(--primary-color);
  color: #fff;
  border-radius: 4px;
  transition: all 0.3s ease;
}

.sidebar-link:hover {
  background-color: #1c2a51;
  text-decoration: none;
}

.contact-info {
  background-color: var(--light-bg-color);
  padding: 20px;
  border-radius: 8px;
}

.contact-info h3 {
  color: var(--text-color);
  margin-bottom: 10px;
}

.contact-info p {
  color: var(--light-text-color);
  margin-bottom: 5px;
}

/* Footer */
.footer {
  background-color: var(--footer-color);
  color: #fff;
  padding: 30px 0;
}

.footer-inner {
  text-align: center;
}

.copyright {
  font-size: 1.4rem;
}

/* News List */
.news-list {
  list-style: none;
}

.news-item {
  padding: 15px 0;
  border-bottom: 1px solid var(--border-color);
}

.news-date {
  font-weight: bold;
  margin-bottom: 5px;
  display: block;
}

/* Tables */
.table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 20px;
}

.table th,
.table td {
  padding: 12px 15px;
  text-align: left;
  border: 1px solid var(--border-color);
}

.table th {
  background-color: var(--light-bg-color);
  font-weight: bold;
}

/* Responsive */
@media (max-width: 992px) {
  .content-wrapper {
    flex-direction: column;
  }

  .sidebar {
    width: 100%;
  }
}

@media (max-width: 768px) {
  .header-inner {
    flex-direction: column;
    height: auto;
    padding: 15px 0;
  }

  .logo {
    margin-bottom: 15px;
  }

  .nav {
    width: 100%;
  }

  .nav-list {
    flex-direction: column;
    width: 100%;
  }

  .nav-item {
    margin-left: 0;
    margin-bottom: 5px;
  }

  .nav-link {
    padding: 10px;
    text-align: center;
  }

  .nav-toggle {
    display: block;
    position: absolute;
    top: 20px;
    right: 20px;
  }

  .nav.active .nav-list {
    display: flex;
  }

  .nav:not(.active) .nav-list {
    display: none;
  }
}

/* Utility Classes */
.text-center {
  text-align: center;
}

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: 10px; }
.mt-2 { margin-top: 20px; }
.mt-3 { margin-top: 30px; }
.mt-4 { margin-top: 40px; }

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: 10px; }
.mb-2 { margin-bottom: 20px; }
.mb-3 { margin-bottom: 30px; }
.mb-4 { margin-bottom: 40px; }

.p-0 { padding: 0; }
.p-1 { padding: 10px; }
.p-2 { padding: 20px; }
.p-3 { padding: 30px; }
.p-4 { padding: 40px; }

/* Specific Page Styles */
.chairman-greeting {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  align-items: flex-start;
}

.chairman-image {
  width: 150px;
  margin-right: 20px;
  margin-bottom: 20px;
  float: left;
}

.rotary-songs {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 20px;
}

.rotary-song {
  background-color: var(--light-bg-color);
  padding: 20px;
  border-radius: 8px;
}

.rotary-song h3 {
  margin-bottom: 15px;
  color: var(--primary-color);
}