@import url('https://fonts.googleapis.com/css2?family=Noto+Serif+JP:wght@400;600;700&family=Shippori+Mincho:wght@500;700&display=swap');

/* ==========================================================================
   Sound Healing Room - 響きの待合室 - 
   Classic & Structured Design System (style.css)
   装飾を削ぎ落とし、読みやすさと信頼感を追求した伝統的なメディアデザイン
   ========================================================================== */

:root {
  --bg-page: #fcfcfc;
  --bg-surface: #ffffff;
  --bg-subtle: #f4f4f5;
  --bg-tint: #f8fafc;

  --border-light: #e4e4e7;
  --border-dark: #71717a;

  --text-main: #18181b;
  --text-sub: #3f3f46;
  --text-muted: #71717a;

  --primary: #1e3a8a;       /* 落ち着いた正統派の濃紺 */
  --primary-hover: #172554;
  --accent-navy: #0f172a;
  --youtube-red: #c00;

  --font-base: "Hiragino Kaku Gothic ProN", "Hiragino Sans", "Yu Gothic", Meiryo, sans-serif;
  --font-serif: "Shippori Mincho", "Noto Serif JP", "Hiragino Mincho ProN", "Yu Mincho", serif;
  
  --radius: 3px; /* 昔ながらの端正な微細角丸 */
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-base);
  background-color: var(--bg-page);
  color: var(--text-main);
  line-height: 1.85;
  letter-spacing: 0.03em;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: var(--primary);
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: color 0.15s ease;
}

a:hover {
  color: var(--primary-hover);
}

img, iframe {
  max-width: 100%;
  height: auto;
  border: none;
  display: block;
}

/* --- Containers --- */
.container {
  width: 100%;
  max-width: 1000px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.container-narrow {
  width: 100%;
  max-width: 780px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* --- Header (Traditional & Formal) --- */
.site-header {
  background-color: #ffffff;
  border-bottom: 2px solid #18181b;
  padding: 1.25rem 0;
  position: relative;
  z-index: 1000;
}

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

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  text-decoration: none !important;
}

.brand-logo-img {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1px solid var(--border-light);
}

.brand-title {
  display: flex;
  flex-direction: column;
}

.brand-title span:first-child {
  font-size: 1.2rem;
  font-weight: 800;
  color: #18181b;
  letter-spacing: 0.04em;
}

.brand-sub {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-weight: 500;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 1.75rem;
}

.nav-link {
  color: #27272a;
  font-size: 0.95rem;
  font-weight: 600;
  text-decoration: none !important;
  padding: 0.25rem 0;
  border-bottom: 2px solid transparent;
}

.nav-link:hover, .nav-link.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
}

.nav-cta {
  background: var(--youtube-red);
  color: #ffffff !important;
  padding: 0.5rem 1.15rem;
  border-radius: var(--radius);
  font-size: 0.875rem;
  font-weight: 700;
  text-decoration: none !important;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

.nav-cta:hover {
  background: #990000;
}

.menu-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border-light);
  padding: 0.35rem 0.6rem;
  font-size: 1.1rem;
  cursor: pointer;
}

/* --- Standard Buttons & Badges --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.65rem 1.4rem;
  font-size: 0.925rem;
  font-weight: 700;
  text-decoration: none !important;
  border-radius: var(--radius);
  transition: all 0.2s ease;
  cursor: pointer;
  line-height: 1.4;
}

.btn-primary {
  background: var(--primary);
  color: #ffffff !important;
  border: 1px solid var(--primary);
  box-shadow: 0 2px 6px rgba(30, 58, 138, 0.15);
}

.btn-primary:hover {
  background: var(--primary-hover);
  border-color: var(--primary-hover);
  transform: translateY(-1px);
  box-shadow: 0 4px 10px rgba(30, 58, 138, 0.25);
}

.btn-secondary {
  background: #ffffff;
  color: var(--primary) !important;
  border: 1px solid var(--primary);
}

.btn-secondary:hover {
  background: #f8fafc;
  border-color: var(--primary-hover);
  color: var(--primary-hover) !important;
  transform: translateY(-1px);
}

.btn-youtube {
  background: var(--youtube-red);
  color: #ffffff !important;
  border: 1px solid var(--youtube-red);
  box-shadow: 0 2px 6px rgba(204, 0, 0, 0.15);
}

.btn-youtube:hover {
  background: #a30000;
  border-color: #a30000;
  transform: translateY(-1px);
}

.badge {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.25rem 0.65rem;
  border-radius: var(--radius);
  letter-spacing: 0.04em;
}

/* --- Hero (バナー画像を活かした洗練されたダーク音響デザイン) --- */
.hero {
  background-color: #080c14;
  background-image: 
    linear-gradient(180deg, rgba(8, 12, 20, 0.7) 0%, rgba(8, 12, 20, 0.4) 50%, rgba(8, 12, 20, 0.85) 100%),
    url('images/hero-banner.png');
  background-position: center center;
  background-repeat: no-repeat;
  background-size: cover;
  border-bottom: 2px solid #1e293b;
  padding: 4.25rem 0 3rem;
  text-align: center;
  position: relative;
  overflow: hidden;
  color: #ffffff;
}

.hero::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, #1e3a8a 0%, #38bdf8 50%, #1e3a8a 100%);
  z-index: 3;
}

.hero-canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 1;
}

.hero-inner {
  max-width: 860px;
  margin: 0 auto;
  position: relative;
  z-index: 2;
}

.hero-tag-simple {
  display: inline-block;
  font-size: 0.825rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: #93c5fd;
  background: rgba(15, 23, 42, 0.65);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid rgba(147, 197, 253, 0.35);
  padding: 0.35rem 1.25rem;
  margin-bottom: 1.25rem;
  border-radius: 30px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.hero-title {
  font-family: var(--font-serif);
  font-size: clamp(2rem, 4.2vw, 2.75rem);
  font-weight: 700;
  color: #ffffff;
  line-height: 1.4;
  letter-spacing: 0.05em;
  margin-bottom: 1rem;
  text-shadow: 0 2px 12px rgba(0, 0, 0, 0.7);
}

.hero-lead-concise {
  font-size: 1.05rem;
  color: #cbd5e1;
  max-width: 680px;
  margin: 0 auto 1.85rem;
  line-height: 1.8;
  text-shadow: 0 1px 6px rgba(0, 0, 0, 0.6);
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 0.85rem;
  flex-wrap: wrap;
  margin-bottom: 2.25rem;
}

.hero-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.85rem;
  font-size: 0.95rem;
  font-weight: 700;
  text-decoration: none !important;
  border-radius: var(--radius);
  transition: all 0.2s ease;
  letter-spacing: 0.02em;
}

.hero-btn-primary {
  background: #2563eb;
  color: #ffffff !important;
  border: 1px solid #3b82f6;
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.4);
}

.hero-btn-primary:hover {
  background: #1d4ed8;
  border-color: #60a5fa;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(37, 99, 235, 0.55);
}

.hero-btn-secondary {
  background: rgba(255, 255, 255, 0.12);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  color: #ffffff !important;
  border: 1.5px solid rgba(255, 255, 255, 0.6);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.hero-btn-secondary:hover {
  background: rgba(255, 255, 255, 0.25);
  border-color: #ffffff;
  color: #ffffff !important;
  transform: translateY(-2px);
}

.btn-play-icon {
  font-size: 0.8rem;
  color: #93c5fd;
}

/* 3つの特徴バー（端的に横並び・グラスモーフィズム） */
.hero-features-bar {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 0.85rem;
  flex-wrap: wrap;
  padding-top: 1.85rem;
  border-top: 1px solid rgba(255, 255, 255, 0.15);
}

.feature-bar-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.85rem;
  color: #cbd5e1;
  background: rgba(15, 23, 42, 0.6);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  border: 1px solid rgba(255, 255, 255, 0.15);
  padding: 0.5rem 1.05rem;
  border-radius: var(--radius);
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.25);
}

.feature-bar-pill strong {
  color: #ffffff;
}

.pill-check {
  color: #38bdf8;
  font-size: 0.85rem;
}



@media (max-width: 768px) {
  .hero {
    padding: 2.25rem 0 1.75rem;
  }
  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }
  .hero-btn {
    width: 100%;
  }
  .hero-features-bar {
    flex-direction: column;
    align-items: stretch;
    gap: 0.5rem;
    padding-top: 1.25rem;
  }
  .feature-bar-pill {
    justify-content: flex-start;
  }
  .pc-only {
    display: none;
  }
}

/* --- Structured Section Layout --- */
.section {
  padding: 3rem 0;
}

.section-header {
  margin-bottom: 2rem;
  border-bottom: 2px solid #18181b;
  padding-bottom: 0.75rem;
}

.section-title {
  font-size: 1.45rem;
  font-weight: 800;
  color: #18181b;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.section-desc {
  font-size: 0.925rem;
  color: var(--text-sub);
  margin-top: 0.35rem;
}

/* --- Channel 4 Categories Grid --- */
.channel-category-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

.category-box {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-top: 3px solid var(--primary);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.02);
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.category-box:hover {
  border-color: #cbd5e1;
  transform: translateY(-2px);
}

.category-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.75rem;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.category-badge {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--primary);
  background: #eff6ff;
  border: 1px solid #bfdbfe;
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius);
}

.category-title {
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 700;
  color: #0f172a;
  margin: 0;
}

.category-desc {
  font-size: 0.9rem;
  color: var(--text-sub);
  line-height: 1.7;
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

.category-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.25rem;
  padding-top: 1rem;
  border-top: 1px solid #f1f5f9;
}

.category-link-item {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none !important;
  display: inline-flex;
  align-items: center;
}

.category-link-item:hover {
  color: var(--primary-hover);
  text-decoration: underline !important;
}

.category-link-item.yt-link {
  color: var(--youtube-red);
}

.category-link-item.yt-link:hover {
  color: #a30000;
}

@media (max-width: 960px) {
  .channel-category-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
}

/* --- Traditional Article & Guide Cards --- */
.portal-grid,
.quick-portal-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.portal-box,
.portal-card {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-top: 3px solid var(--primary);
  padding: 1.5rem;
  text-decoration: none !important;
  color: inherit;
  display: flex;
  flex-direction: column;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.portal-box:hover,
.portal-card:hover {
  border-color: var(--border-dark);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.06);
}

.portal-box-meta,
.portal-card-badge {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--primary);
  background: #f1f5f9;
  padding: 0.2rem 0.5rem;
  border-radius: 3px;
  width: fit-content;
  margin-bottom: 0.75rem;
}

.portal-card-badge.highlight {
  color: #b45309;
  background: #fef3c7;
  border: 1px solid #fde68a;
}

.portal-box-title,
.portal-card-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: #18181b;
  margin-bottom: 0.6rem;
  line-height: 1.45;
}

.portal-box-desc,
.portal-card-desc {
  font-size: 0.9rem;
  color: var(--text-sub);
  line-height: 1.7;
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

.portal-box-link,
.portal-card-link {
  font-size: 0.875rem;
  font-weight: 700;
  color: var(--primary);
  margin-top: auto;
}

/* --- Frequency List Index (Structured Table Format) --- */
.freq-index-table {
  width: 100%;
  border-collapse: collapse;
  background: #ffffff;
  border: 1px solid var(--border-light);
  margin-bottom: 2rem;
}

.freq-index-table th, .freq-index-table td {
  padding: 0.9rem 1.1rem;
  border-bottom: 1px solid var(--border-light);
  text-align: left;
  font-size: 0.925rem;
}

.freq-index-table th {
  background: var(--bg-subtle);
  font-weight: 700;
  color: #18181b;
  width: 25%;
}

.freq-index-table tr:hover td {
  background: #fbfbfb;
}

/* --- Responsive Article Data Tables --- */
.data-table-wrap {
  width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin: 1.5rem 0 2rem;
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  background: #ffffff;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  min-width: 560px; /* スマホ表示でも列が極端に潰れず横スクロールで快適に読める */
}

.data-table th, .data-table td {
  padding: 0.85rem 1rem;
  border-bottom: 1px solid var(--border-light);
  border-right: 1px solid var(--border-light);
  text-align: left;
  font-size: 0.925rem;
  line-height: 1.6;
}

.data-table th:last-child, .data-table td:last-child {
  border-right: none;
}

.data-table th {
  background: var(--bg-subtle);
  font-weight: 700;
  color: #18181b;
  white-space: nowrap;
}

.data-table tr:hover td {
  background: #fbfbfb;
}

/* --- Buttons (Clean & Solid) --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.6rem;
  font-size: 0.95rem;
  font-weight: 700;
  border-radius: var(--radius);
  text-decoration: none !important;
  cursor: pointer;
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--primary);
  color: #ffffff !important;
}

.btn-primary:hover {
  background: var(--primary-hover);
}

.btn-secondary {
  background: #ffffff;
  border: 1px solid var(--border-dark);
  color: #18181b !important;
}

.btn-secondary:hover {
  background: var(--bg-subtle);
}

.btn-youtube {
  background: var(--youtube-red);
  color: #ffffff !important;
}

.btn-youtube:hover {
  background: #990000;
}

/* --- Article Detail Styling (長文読書に最適化したレイアウト) --- */
.article-header {
  padding: 2.5rem 0 1.5rem;
  border-bottom: 1px solid var(--border-light);
  margin-bottom: 2rem;
}

.article-category {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 0.5rem;
}

.article-title {
  font-size: clamp(1.6rem, 3.5vw, 2.15rem);
  font-weight: 800;
  color: #09090b;
  line-height: 1.4;
  margin-bottom: 0.85rem;
}

.article-meta {
  color: var(--text-muted);
  font-size: 0.85rem;
  display: flex;
  gap: 1rem;
  align-items: center;
}

.article-content {
  font-size: 1.05rem;
  line-height: 1.95;
  color: #27272a;
}

.article-content h2 {
  font-size: 1.45rem;
  font-weight: 800;
  color: #09090b;
  margin: 3rem 0 1.25rem;
  padding: 0.4rem 0 0.4rem 0.75rem;
  border-left: 5px solid var(--primary);
  border-bottom: 1px solid var(--border-light);
  background: #fbfbfb;
}

.article-content h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: #18181b;
  margin: 2rem 0 0.75rem;
  padding-bottom: 0.3rem;
  border-bottom: 1px dotted var(--border-light);
}

.article-content p {
  margin-bottom: 1.65rem;
}

.article-content ul, .article-content ol {
  margin-bottom: 1.75rem;
  padding-left: 1.5rem;
}

.article-content li {
  margin-bottom: 0.5rem;
}

.article-content strong {
  font-weight: 700;
  color: #09090b;
}

/* --- Table of Contents (プロ仕様・開閉式目次ボックス) --- */
.toc-box {
  background: #ffffff;
  border: 1px solid #c7d7ee;
  border-radius: 6px;
  padding: 1.25rem 1.6rem;
  margin: 2.25rem 0;
  box-shadow: 0 2px 8px rgba(30, 58, 138, 0.04);
}

.toc-header {
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  list-style: none;
  user-select: none;
  padding: 0.25rem 0;
}

.toc-header::-webkit-details-marker {
  display: none;
}

.toc-header::marker {
  display: none;
}

.toc-title {
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--primary);
  letter-spacing: 0.05em;
}

.toc-toggle {
  font-size: 0.85rem;
  color: #2563eb;
  font-weight: 500;
}

.toc-toggle-state::after {
  content: "閉じる";
}

.toc-box:not([open]) .toc-toggle-state::after {
  content: "開く";
}

.toc-box:not([open]) {
  padding-bottom: 1.25rem;
}

.toc-content {
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px dashed #dbeafe;
}

.toc-list {
  list-style: none;
  padding-left: 0;
  margin-bottom: 0;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.toc-list li {
  font-size: 0.95rem;
  line-height: 1.6;
}

.toc-list a {
  color: #1e3a8a;
  text-decoration: underline;
  text-underline-offset: 3px;
  font-weight: 600;
  transition: color 0.15s ease;
}

.toc-list a:hover {
  color: #2563eb;
  text-decoration-thickness: 2px;
}

.toc-list li.toc-sub,
.toc-list li:has(> a[href*="-"]) {
  padding-left: 1.25rem;
  font-size: 0.9rem;
}

.toc-list li.toc-sub a {
  font-weight: 400;
}

/* --- PubMed Research Box --- */
.research-box {
  background: #ffffff;
  border: 2px solid #94a3b8;
  padding: 1.5rem;
  margin: 2.25rem 0;
}

.research-box-title {
  font-size: 1.05rem;
  font-weight: 800;
  color: var(--primary);
  margin-bottom: 0.85rem;
  border-bottom: 1px solid #cbd5e1;
  padding-bottom: 0.5rem;
}

.research-box-list {
  list-style: square;
  padding-left: 1.5rem;
  margin-bottom: 1rem;
}

.research-box-list li {
  margin-bottom: 0.65rem;
  font-size: 0.95rem;
}

.research-source {
  font-size: 0.825rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border-light);
  padding-top: 0.75rem;
  margin-top: 0.75rem;
}

/* --- Traditional Disclaimer Box --- */
.disclaimer-box {
  background: #fafaf9;
  border: 1px solid #d6d3d1;
  padding: 1.15rem 1.35rem;
  margin: 2rem 0;
  font-size: 0.9rem;
  color: #57534e;
  line-height: 1.7;
}

.disclaimer-title {
  font-weight: 800;
  color: #292524;
  margin-bottom: 0.4rem;
}

/* --- Video Embed Section --- */
.video-feature-card {
  background: #ffffff;
  border: 1px solid var(--border-light);
  padding: 1.5rem;
  margin: 2.5rem 0;
}

.video-container {
  position: relative;
  width: 100%;
  padding-bottom: 56.25%;
  height: 0;
  background: #000000;
}

.video-container iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

.video-meta {
  padding-top: 1.25rem;
}

.video-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 0.6rem;
}

.video-desc {
  font-size: 0.925rem;
  color: var(--text-sub);
  margin-bottom: 1.25rem;
}

.video-cta-group {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

/* --- FAQ Traditional Accordion --- */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin: 2rem 0;
}

.faq-item {
  border: 1px solid var(--border-light);
  background: #ffffff;
}

.faq-question {
  padding: 1rem 1.25rem;
  font-weight: 700;
  font-size: 1rem;
  color: #18181b;
  cursor: pointer;
  list-style: none;
  background: #fafafa;
}

.faq-question::-webkit-details-marker {
  display: none;
}

.faq-answer {
  padding: 1rem 1.25rem;
  font-size: 0.95rem;
  color: var(--text-sub);
  line-height: 1.8;
  border-top: 1px solid var(--border-light);
}

/* --- Breadcrumb --- */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin: 1.25rem 0;
  flex-wrap: wrap;
}

.breadcrumb a {
  color: var(--text-sub);
  text-decoration: none;
}

.breadcrumb a:hover {
  text-decoration: underline;
}

/* --- Footer --- */
.site-footer {
  margin-top: auto;
  background-color: #ffffff;
  border-top: 2px solid #18181b;
  padding: 3rem 0 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 2.5rem;
  margin-bottom: 2.5rem;
}

.footer-brand,
.footer-brand-title {
  font-size: 1.15rem;
  font-weight: 800;
  color: #18181b;
  margin-bottom: 0.5rem;
}

.footer-desc,
.footer-brand-desc {
  color: var(--text-sub);
  font-size: 0.9rem;
  line-height: 1.75;
}

.footer-col-title,
.footer-heading {
  font-size: 0.95rem;
  font-weight: 800;
  color: #18181b;
  margin-bottom: 0.85rem;
  border-bottom: 1px solid var(--border-light);
  padding-bottom: 0.4rem;
}

.footer-links,
.footer-nav {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  padding-left: 0;
  margin: 0;
}

.footer-links a,
.footer-nav a {
  color: var(--text-sub);
  font-size: 0.9rem;
  text-decoration: underline;
  text-underline-offset: 2px;
}

.footer-links a:hover,
.footer-nav a:hover {
  color: var(--primary);
}

.footer-bottom {
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-light);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.825rem;
  color: var(--text-muted);
  flex-wrap: wrap;
  gap: 0.75rem;
}

@media (max-width: 768px) {
  /* Layout & Containers */
  .container,
  .container-narrow {
    padding: 0 1.15rem;
  }

  .site-header {
    position: relative;
    z-index: 1000;
    padding: 0.85rem 0;
  }

  .menu-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    background: #ffffff;
    border: 1px solid var(--border-light);
    border-radius: var(--radius);
    padding: 0.4rem 0.65rem;
    font-size: 1.25rem;
    cursor: pointer;
    color: #18181b;
  }

  .main-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    width: 100%;
    background: #ffffff;
    border-bottom: 3px solid var(--primary);
    box-shadow: 0 12px 28px rgba(0, 0, 0, 0.18);
    flex-direction: column;
    padding: 0.75rem 1.25rem 1.25rem;
    gap: 0.25rem;
    z-index: 1001;
  }

  .main-nav.is-open,
  .main-nav.active {
    display: flex;
  }

  .main-nav .nav-link {
    display: block;
    width: 100%;
    padding: 0.75rem 0.5rem;
    font-size: 1rem;
    font-weight: 700;
    color: #18181b;
    border-bottom: 1px solid var(--border-light);
    text-align: center;
    text-decoration: none !important;
  }

  .main-nav .nav-link:hover,
  .main-nav .nav-link.active {
    color: var(--primary);
    background: rgba(30, 58, 138, 0.05);
    border-radius: var(--radius);
    border-bottom-color: var(--border-light);
  }

  .main-nav .nav-cta {
    display: flex;
    width: 100%;
    justify-content: center;
    padding: 0.8rem 1rem;
    margin-top: 0.6rem;
    font-size: 0.95rem;
  }

  /* Section & Typography on Mobile */
  .section {
    padding: 2.25rem 0;
  }

  .section-header {
    margin-bottom: 1.5rem;
  }

  .section-title {
    font-size: 1.3rem;
  }

  .article-title {
    font-size: 1.45rem;
    line-height: 1.38;
    margin-bottom: 0.75rem;
  }

  .article-meta {
    flex-wrap: wrap;
    gap: 0.4rem 0.85rem;
    font-size: 0.8rem;
    line-height: 1.4;
  }

  .article-content {
    font-size: 0.985rem;
    line-height: 1.85;
  }

  .article-content h2 {
    font-size: 1.25rem;
    margin: 2.25rem 0 0.95rem;
    padding: 0.4rem 0.5rem 0.4rem 0.7rem;
    line-height: 1.4;
  }

  .article-content h3 {
    font-size: 1.1rem;
    margin: 1.65rem 0 0.6rem;
    line-height: 1.4;
  }

  .article-content p {
    margin-bottom: 1.35rem;
  }

  .article-content ul,
  .article-content ol {
    padding-left: 1.25rem;
    margin-bottom: 1.4rem;
  }

  /* Content Boxes */
  .toc-box,
  .info-box,
  .research-box,
  .disclaimer-box {
    padding: 1.15rem 1rem;
    margin: 1.5rem 0;
    font-size: 0.925rem;
  }

  /* Video Feature Card & CTAs */
  .video-feature-card {
    padding: 1rem;
    margin: 1.75rem 0;
  }

  .video-title {
    font-size: 1.05rem;
    line-height: 1.45;
  }

  .video-desc {
    font-size: 0.875rem;
    line-height: 1.65;
    margin-bottom: 1rem;
  }

  .video-cta-group {
    flex-direction: column;
    gap: 0.65rem;
  }

  .video-cta-group .btn {
    width: 100%;
    justify-content: center;
  }

  /* Grid Layouts & Cards */
  .portal-grid,
  .quick-portal-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  .portal-box,
  .portal-card {
    padding: 1.15rem 1rem;
  }

  /* Tables on Mobile */
  .data-table-wrap {
    margin: 1.25rem 0 1.5rem;
    box-shadow: inset -4px 0 6px rgba(0, 0, 0, 0.04);
  }

  .data-table th,
  .data-table td {
    padding: 0.65rem 0.75rem;
    font-size: 0.85rem;
  }

  /* Breadcrumb & Navigation */
  .breadcrumb {
    font-size: 0.8rem;
    margin: 0.85rem 0;
    gap: 0.35rem;
  }

  /* FAQ Accordion */
  .faq-question {
    padding: 0.85rem 1rem;
    font-size: 0.95rem;
  }

  .faq-answer {
    padding: 0.85rem 1rem;
    font-size: 0.9rem;
    line-height: 1.7;
  }

  /* Footer */
  .site-footer {
    padding: 2.25rem 0 1.5rem;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 1.75rem;
    margin-bottom: 1.75rem;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 1.6rem;
    line-height: 1.3;
  }

  .hero-tag-simple {
    font-size: 0.75rem;
    padding: 0.3rem 0.7rem;
  }

  .hero-lead-concise {
    font-size: 0.9rem;
    line-height: 1.6;
  }

  .article-title {
    font-size: 1.3rem;
  }

  .brand-title span:first-child {
    font-size: 1.05rem;
  }

  .brand-sub {
    font-size: 0.7rem;
  }

  .brand-logo-img {
    width: 38px;
    height: 38px;
  }
}