:root {
  --color-primary: #140078;
  --color-hover-bg: #0d0052;
  --color-border: #f8ffff;
  --color-accent: #64c8ff;
  --color-text-main: #f8ffff;
  --color-text-sub: rgba(248, 255, 255, 0.7);
}

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

html {
  scroll-behavior: smooth;
  height: auto;
}

body {
  font-family: 'Noto Sans JP', sans-serif;
  background-color: var(--color-primary);
  color: var(--color-text-main);
  line-height: 1.6;
  width: 100%;
  min-height: 100vh;
}

/* =======================================
   固定ヘッダー
======================================= */
header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 60px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 2.5rem;
  background: rgba(20, 0, 120, 0.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
  z-index: 1000;
}

.logo {
  font-family: 'Montserrat', sans-serif;
  font-weight: 800;
  font-size: 1.3rem;
  letter-spacing: 0.05em;
}

.logo a {
  color: var(--color-text-main);
  text-decoration: none;
}

nav a {
  color: var(--color-text-main);
  text-decoration: none;
  margin-left: 2rem;
  font-size: 0.9rem;
  font-weight: 500;
  transition: color 0.2s;
}

nav a:hover {
  color: var(--color-accent);
}

/* =======================================
   ヒーローエリア（3分割アコーディオン）
======================================= */
.hero-accordion {
  position: relative;
  width: 100%;
  height: 100vh;
  height: 100dvh;
  padding-top: 60px;
  overflow: hidden;
  background-color: var(--color-primary);
}

.accordion-container {
  display: flex;
  width: 100%;
  height: 100%;
}

.accordion-item {
  flex: 1;
  height: 100%;
  position: relative;
  overflow: hidden;
  border-right: 1px solid var(--color-border);
  transition: flex 0.45s cubic-bezier(0.25, 1, 0.5, 1), background-color 0.35s ease;
  cursor: pointer;
  background-color: var(--color-primary);
}

.accordion-item:last-child {
  border-right: none;
}

.preview-title {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  white-space: nowrap;
  pointer-events: none;
  transition: opacity 0.25s ease;
}

.preview-title h2 {
  font-family: 'Montserrat', sans-serif;
  font-size: 2.8rem;
  font-weight: 800;
  letter-spacing: 0.1em;
  color: var(--color-text-main);
}

.detail-content {
  opacity: 0;
  visibility: hidden;
  padding: 5rem 3.5rem;
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  transition: opacity 0.3s ease 0.15s;
}

.detail-content h3 {
  font-family: 'Montserrat', sans-serif;
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--color-text-main);
  margin-bottom: 0.5rem;
}

.divider {
  width: 48px;
  height: 3px;
  background-color: var(--color-accent);
  margin-bottom: 1.5rem;
}

.detail-content .desc {
  font-size: 1rem;
  line-height: 1.8;
  max-width: 440px;
  color: var(--color-text-main);
  margin-bottom: 2rem;
}

.accordion-item:hover {
  flex: 3.5;
  background-color: var(--color-hover-bg) !important;
}

.accordion-item:hover .preview-title {
  opacity: 0;
}

.accordion-item:hover .detail-content {
  opacity: 1;
  visibility: visible;
}

.view-more {
  display: inline-block;
  margin-top: auto;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--color-text-main);
  text-decoration: none;
  border-bottom: 2px solid var(--color-accent);
  padding-bottom: 2px;
  width: fit-content;
  transition: transform 0.2s ease, color 0.2s ease;
}

.view-more:hover {
  color: var(--color-accent);
  transform: translateX(6px);
}

/* SNS リスト */
.sns-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  max-width: 320px;
}

.sns-list a {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.75rem 1.25rem;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  color: var(--color-text-main);
  text-decoration: none;
  font-weight: 600;
  transition: all 0.2s ease;
}

.sns-list a:hover {
  background-color: var(--color-accent);
  color: var(--color-primary);
  border-color: var(--color-accent);
  transform: translateX(4px);
}

/* =======================================
   スクロール誘導インジケーター（シンプル表示専用）
======================================= */
.scroll-indicator {
  position: fixed;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  color: var(--color-text-main);
  font-size: 0.75rem;
  font-family: 'Montserrat', sans-serif;
  letter-spacing: 0.15em;
  opacity: 0.8;
  transition: opacity 0.3s ease, visibility 0.3s ease;
  z-index: 900;
  pointer-events: none; /* マウスやタップの操作を完全に透過 */
  user-select: none;
}

.scroll-indicator.hidden {
  opacity: 0;
  visibility: hidden;
}

.arrow-down {
  color: var(--color-accent);
  font-size: 0.85rem;
  animation: bounce 1.8s infinite;
}

@keyframes bounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(6px); }
}

/* =======================================
   NEWS セクション
======================================= */
.news-section {
  padding: 6rem 2rem;
  background-color: var(--color-primary);
  border-top: 1px solid var(--color-border);
  min-height: 50vh;
  display: flex;
  justify-content: center;
}

.news-container {
  width: 100%;
  max-width: 860px;
}

.section-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  margin-bottom: 2.5rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--color-border);
}

.header-title-group h2 {
  font-family: 'Montserrat', sans-serif;
  font-size: 2rem;
  font-weight: 800;
  letter-spacing: 0.05em;
  color: var(--color-text-main);
  line-height: 1.1;
}

.header-title-group .sub-label {
  font-size: 0.85rem;
  color: var(--color-text-sub);
}

.news-more-btn {
  font-family: 'Montserrat', sans-serif;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--color-text-main);
  text-decoration: none;
  border-bottom: 2px solid var(--color-accent);
  padding-bottom: 2px;
  transition: color 0.2s ease, transform 0.2s ease;
}

.news-more-btn:hover {
  color: var(--color-accent);
  transform: translateX(4px);
}

.news-list {
  list-style: none;
  display: flex;
  flex-direction: column;
}

.news-item {
  display: flex;
  flex-direction: column;
  padding: 1.5rem 0;
  border-bottom: 1px solid var(--color-border);
}

.news-meta {
  display: flex;
  align-items: baseline;
  margin-bottom: 0.5rem;
}

.news-date {
  font-family: 'Montserrat', sans-serif;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-accent);
  min-width: 120px;
  flex-shrink: 0;
}

.news-item-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--color-text-main);
}

.news-item-title a {
  color: inherit;
  text-decoration: none;
  transition: color 0.2s;
}

.news-item-title a:hover {
  color: var(--color-accent);
}

.ext-icon {
  font-size: 0.8rem;
  color: var(--color-accent);
  margin-left: 0.2rem;
}

.news-item-content {
  font-size: 0.95rem;
  color: var(--color-text-main);
  line-height: 1.8;
  padding-left: 120px;
  opacity: 0.9;
}

.news-item-content p {
  margin-bottom: 0.5rem;
}

.news-item-content a {
  color: var(--color-accent);
}

.loading, .empty, .error {
  color: var(--color-text-sub);
  font-size: 0.9rem;
  padding: 2rem 0;
}

/* =======================================
   下層ページ共通スタイル (/about/, /news/)
======================================= */
.page-container {
  max-width: 860px;
  margin: 0 auto;
  padding: 120px 2rem 5rem;
  min-height: calc(100vh - 80px);
}

.page-title {
  font-family: 'Montserrat', sans-serif;
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--color-text-main);
  margin-bottom: 0.5rem;
}

.page-body {
  margin-top: 2.5rem;
  line-height: 1.9;
}

.page-body h4 {
  font-size: 1.25rem;
  color: var(--color-accent);
  margin: 2rem 0 0.8rem;
}

.news-all-list {
  margin-top: 2rem;
  list-style: none;
}

.back-link {
  display: inline-block;
  margin-top: 3rem;
  color: var(--color-accent);
  text-decoration: none;
  font-weight: 700;
  transition: transform 0.2s ease;
}

.back-link:hover {
  transform: translateX(-4px);
}

/* =======================================
   フッター
======================================= */
footer {
  padding: 2.5rem;
  text-align: center;
  background-color: var(--color-primary);
  border-top: 1px solid var(--color-border);
}

.copyright {
  font-family: 'Montserrat', sans-serif;
  font-size: 0.8rem;
  color: var(--color-text-sub);
}

/* =======================================
   レスポンシブ対応（スマホ向け）
======================================= */
@media (max-width: 768px) {
  header {
    padding: 0 1.25rem;
  }
  
  nav a {
    margin-left: 1rem;
    font-size: 0.85rem;
  }

  .accordion-container {
    flex-direction: column;
  }

  .accordion-item {
    border-right: none;
    border-bottom: 1px solid var(--color-border);
  }

  .preview-title h2 {
    font-size: 1.8rem;
  }

  .detail-content {
    padding: 2rem 1.5rem;
  }

  .detail-content h3 {
    font-size: 1.8rem;
  }

  .accordion-item:hover {
    flex: 2.5;
  }

  .scroll-indicator {
    bottom: 12px;
  }

  .news-meta {
    flex-direction: column;
    gap: 0.25rem;
  }

  .news-item-content {
    padding-left: 0;
    margin-top: 0.5rem;
  }
}