:root {
  --bg: #f3f7f4;
  --surface: #ffffff;
  --surface-alt: #fcfdfe;
  --ink: #141b17;
  --muted: #536258;
  --line: rgba(20, 27, 23, 0.08);
  --line-strong: rgba(20, 27, 23, 0.16);
  --accent: #225c43;
  --accent-light: #e6f3ec;
  --accent-hover: #194532;
  --warm: #cd7c34;
  --warm-light: #fdf5ee;
  --shadow-sm: 0 4px 12px rgba(20, 27, 23, 0.04);
  --shadow: 0 16px 40px rgba(20, 27, 23, 0.08);
  --shadow-hover: 0 24px 48px rgba(20, 27, 23, 0.14);
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
  --transition-fast: all 0.16s ease;
  font-family: "Inter", "Noto Sans JP", "Yu Gothic", system-ui, -apple-system, sans-serif;
}

* { 
  box-sizing: border-box; 
}

html { 
  scroll-behavior: smooth; 
  scroll-padding-top: 80px;
}

body { 
  margin: 0; 
  background: var(--bg); 
  color: var(--ink); 
  letter-spacing: -0.01em; 
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { 
  color: inherit; 
  text-decoration: none; 
}

/* スクロールバーのカスタマイズ */
::-webkit-scrollbar {
  width: 10px;
}
::-webkit-scrollbar-track {
  background: var(--bg);
}
::-webkit-scrollbar-thumb {
  background: rgba(20, 27, 23, 0.2);
  border-radius: var(--radius-sm);
  border: 2px solid var(--bg);
}
::-webkit-scrollbar-thumb:hover {
  background: rgba(20, 27, 23, 0.4);
}

/* ヘッダー */
.site-header {
  position: sticky; 
  top: 0; 
  z-index: 100;
  display: flex; 
  justify-content: space-between; 
  gap: 16px; 
  align-items: center;
  padding: 16px 24px;
  background: rgba(243, 247, 244, 0.85);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  transition: var(--transition-fast);
}

.site-header.scrolled {
  padding: 12px 24px;
  box-shadow: var(--shadow-sm);
}

.brand { 
  display: inline-flex; 
  align-items: center; 
  gap: 10px; 
  font-weight: 900; 
  font-size: 1.1rem;
}

.brand-icon { 
  width: 34px; 
  height: 34px; 
  border-radius: var(--radius-sm); 
  object-fit: cover; 
  border: 1px solid var(--line); 
}

.nav-menu { 
  display: flex; 
  gap: 8px; 
  flex-wrap: wrap; 
  font-size: 0.9rem; 
  font-weight: 700; 
}

.nav-menu a { 
  padding: 8px 14px; 
  border-radius: var(--radius-sm); 
  color: var(--muted);
  transition: var(--transition-fast);
}

.nav-menu a:hover,
.nav-menu a.active { 
  background: var(--accent-light); 
  color: var(--accent); 
}

/* ヒーローセクション */
.hero { 
  position: relative; 
  min-height: 85svh; 
  padding: 80px 24px; 
  display: flex;
  align-items: center;
  overflow: hidden; 
}

.hero::before {
  content: "";
  position: absolute; 
  inset: 0;
  background-image:
    linear-gradient(90deg, rgba(243, 247, 244, 0.98) 0%, rgba(243, 247, 244, 0.85) 50%, rgba(243, 247, 244, 0.2) 100%),
    url("../img/education-hero.png");
  background-position: center right;
  background-size: cover;
  z-index: 0;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 800px;
}

.label { 
  display: inline-block;
  color: var(--accent); 
  font-size: 0.8rem; 
  font-weight: 900; 
  letter-spacing: 0.16em; 
  text-transform: uppercase; 
  margin-bottom: 16px;
  background: var(--accent-light);
  padding: 4px 12px;
  border-radius: 20px;
}

h1, h2, h3, h4, p { 
  margin-top: 0; 
}

h1 { 
  font-size: clamp(2.2rem, 6vw, 4.2rem); 
  line-height: 1.1; 
  margin-bottom: 24px; 
  font-weight: 900;
  letter-spacing: -0.02em;
}

h2 { 
  font-size: clamp(1.8rem, 4.5vw, 2.6rem); 
  line-height: 1.2; 
  margin-bottom: 32px; 
  font-weight: 900;
  letter-spacing: -0.01em;
}

p { 
  color: var(--muted); 
  line-height: 1.8; 
}

.hero p:not(.label) { 
  font-size: clamp(1.05rem, 2vw, 1.25rem); 
  margin-bottom: 36px;
  max-width: 680px;
  font-weight: 500;
}

/* ボタン */
.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 16px 32px;
  font-weight: 700;
  font-size: 1rem;
  border-radius: var(--radius-sm);
  transition: var(--transition-fast);
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 4px 14px rgba(34, 92, 67, 0.3);
}

.btn-primary:hover {
  background: var(--accent-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(34, 92, 67, 0.4);
}

.btn-secondary {
  background: transparent;
  color: var(--accent);
  border: 2px solid var(--accent);
}

.btn-secondary:hover {
  background: rgba(34, 92, 67, 0.05);
  transform: translateY(-2px);
}

.btn-secondary-light {
  background: rgba(255, 255, 255, 0.1);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.btn-secondary-light:hover {
  background: rgba(255, 255, 255, 0.2);
  border-color: rgba(255, 255, 255, 0.4);
}

/* ヒーローのスキルダイアグラム */
.diagram {
  position: absolute; 
  right: 48px; 
  bottom: 48px;
  display: grid; 
  grid-template-columns: repeat(2, minmax(110px, 1fr)); 
  gap: 16px;
  width: min(380px, 60vw);
  z-index: 1; 
  opacity: 0.85;
}

.diagram span {
  display: grid; 
  place-items: center;
  min-height: 90px;
  border: 1px solid var(--line-strong);
  background: rgba(255, 255, 255, 0.75);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: var(--shadow);
  font-weight: 800;
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  transition: var(--transition);
}

.diagram span:hover {
  transform: scale(1.05) translateY(-4px);
  background: var(--surface);
  border-color: var(--accent);
  color: var(--accent);
}

/* セクション共通 */
.section { 
  padding: 96px 24px; 
}

/* 概要（Approach） */
.card-grid { 
  display: grid; 
  gap: 24px; 
}

.card { 
  position: relative;
  padding: 40px 32px; 
  background: var(--surface); 
  border: 1px solid var(--line); 
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm); 
  transition: var(--transition);
  overflow: hidden;
}

.card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-hover);
  border-color: var(--line-strong);
}

.card-num {
  font-size: 3rem;
  font-weight: 900;
  color: var(--accent-light);
  line-height: 1;
  margin-bottom: 16px;
}

.card h3 {
  font-size: 1.4rem;
  font-weight: 800;
  margin-bottom: 16px;
}

.card p {
  font-size: 0.95rem;
  margin: 0;
}

/* 講師紹介（Profile） */
.profile-section {
  background: var(--surface-alt);
  border-block: 1px solid var(--line);
}

.profile-container {
  display: grid;
  gap: 32px;
}

.profile-card {
  display: grid;
  gap: 24px;
  padding: 40px 32px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

.profile-avatar-wrapper {
  display: flex;
  justify-content: center;
}

.profile-avatar {
  width: 140px;
  height: 140px;
  border-radius: 50%;
  object-fit: cover;
  border: 4px solid var(--accent-light);
  box-shadow: var(--shadow-sm);
}

.profile-text h3 {
  font-size: 1.6rem;
  margin-bottom: 8px;
  font-weight: 900;
}

.profile-title {
  color: var(--accent);
  font-weight: 700;
  font-size: 0.95rem;
  margin-bottom: 16px;
}

.profile-bio {
  font-size: 0.95rem;
  margin: 0;
  color: var(--muted);
}

.skills-card {
  padding: 40px 32px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

.skills-card h3 {
  font-size: 1.4rem;
  font-weight: 800;
  margin-bottom: 24px;
}

.skills-checklist {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 16px;
}

.skills-checklist li {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px 20px;
  background: var(--bg);
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  font-weight: 700;
  font-size: 0.95rem;
  transition: var(--transition-fast);
}

.skills-checklist li:hover {
  transform: translateX(4px);
  border-color: var(--accent);
  background: var(--accent-light);
  color: var(--accent);
}

.check-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-size: 0.85rem;
  font-weight: bold;
}

/* 実績（Record） */
.record { 
  background: var(--surface); 
  border-bottom: 1px solid var(--line); 
}

.timeline { 
  display: grid; 
  gap: 24px; 
}

.timeline-item { 
  padding: 36px 32px; 
  border-left: 4px solid var(--accent); 
  background: var(--accent-light); 
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  transition: var(--transition);
}

.timeline-item:hover {
  transform: translateX(4px);
  background: #def0e6;
}

.timeline-date { 
  display: inline-block; 
  margin-bottom: 12px; 
  color: var(--warm); 
  font-weight: 800; 
  font-size: 0.9rem;
  background: var(--warm-light);
  padding: 2px 10px;
  border-radius: 4px;
}

.timeline-item h3 {
  font-size: 1.35rem;
  font-weight: 800;
  margin-bottom: 12px;
}

.timeline-item p {
  margin: 0;
  font-size: 0.95rem;
}

/* よくある質問（FAQ） */
.faq-section {
  background: var(--surface-alt);
  border-bottom: 1px solid var(--line);
}

.faq-container {
  max-width: 800px;
  margin: 0 auto;
  display: grid;
  gap: 16px;
}

.faq-item {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: var(--transition);
}

.faq-item:hover {
  border-color: var(--line-strong);
}

.faq-question {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  text-align: left;
  background: transparent;
  border: none;
  padding: 24px;
  font-size: 1.05rem;
  font-weight: 800;
  color: var(--ink);
  cursor: pointer;
  outline: none;
}

.faq-icon {
  position: relative;
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  margin-left: 16px;
}

.faq-icon::before,
.faq-icon::after {
  content: "";
  position: absolute;
  background-color: var(--muted);
  transition: var(--transition);
}

/* 横棒 */
.faq-icon::before {
  top: 9px;
  left: 2px;
  width: 16px;
  height: 2px;
}

/* 縦棒 */
.faq-icon::after {
  top: 2px;
  left: 9px;
  width: 2px;
  height: 16px;
}

.faq-item.active .faq-icon::after {
  transform: rotate(90deg);
  opacity: 0;
}

.faq-item.active .faq-icon::before {
  background-color: var(--accent);
}

.faq-answer {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.3s ease;
}

.faq-item.active .faq-answer {
  grid-template-rows: 1fr;
}

.faq-answer-inner {
  overflow: hidden;
}

.faq-answer p {
  padding: 0 24px 24px;
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.75;
}

/* 問い合わせ（Contact） */
.form-section { 
  background: #101613; 
  color: #fff; 
}

.form-section p.label {
  background: rgba(255, 255, 255, 0.1);
  color: rgba(255, 255, 255, 0.9);
}

.form-section h2 {
  color: #fff;
}

.contact-desc {
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: 40px;
  max-width: 600px;
}

.form-container {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-lg);
  padding: 32px;
  max-width: 900px;
  margin: 0 auto;
}

.google-form { 
  width: 100%; 
  min-height: 600px; 
  border: 1px solid rgba(255, 255, 255, 0.1); 
  border-radius: var(--radius-md);
  background: #ffffff; 
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.form-fallback {
  margin-top: 24px;
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.form-fallback p {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.5);
  margin-bottom: 16px;
}

/* フッター */
.site-footer { 
  padding: 80px 24px 32px; 
  background: #0d1210; 
  color: rgba(255, 255, 255, 0.7); 
  border-top: 1px solid rgba(255, 255, 255, 0.08); 
}

.footer-grid { 
  display: grid; 
  gap: 40px; 
  max-width: 1200px; 
  margin: 0 auto; 
}

.footer-col h4 { 
  margin: 0 0 20px; 
  font-size: 0.85rem; 
  color: rgba(255, 255, 255, 0.4); 
  letter-spacing: 0.16em; 
  text-transform: uppercase; 
  font-weight: 800; 
}

.footer-brand { 
  display: flex; 
  align-items: center; 
  gap: 12px; 
  margin-bottom: 24px; 
}

.footer-icon { 
  width: 44px; 
  height: 44px; 
  border-radius: var(--radius-sm); 
  object-fit: cover; 
  border: 1px solid rgba(255, 255, 255, 0.15); 
}

.footer-brand strong { 
  display: block; 
  color: rgba(255, 255, 255, 0.95); 
  font-size: 1.1rem; 
}

.footer-brand small { 
  display: block; 
  color: rgba(255, 255, 255, 0.5); 
  font-size: 0.8rem; 
  margin-top: 2px; 
}

.footer-copy { 
  margin: 0; 
  font-size: 0.85rem; 
  color: rgba(255, 255, 255, 0.4); 
}

.footer-links { 
  list-style: none; 
  padding: 0; 
  margin: 0; 
  display: grid; 
  gap: 12px; 
}

.footer-links a { 
  display: inline-block; 
  color: rgba(255, 255, 255, 0.7); 
  font-size: 0.95rem; 
  transition: var(--transition-fast); 
}

.footer-links a:hover { 
  color: var(--warm); 
  transform: translateX(2px);
}

.footer-bottom { 
  display: flex; 
  justify-content: space-between; 
  align-items: center; 
  gap: 18px; 
  max-width: 1200px; 
  margin: 48px auto 0; 
  padding-top: 24px; 
  border-top: 1px solid rgba(255, 255, 255, 0.08); 
  font-size: 0.85rem; 
  color: rgba(255, 255, 255, 0.4); 
}

.footer-bottom a { 
  color: rgba(255, 255, 255, 0.7); 
}

.footer-bottom a:hover { 
  color: var(--warm); 
}

/* ページ上部へ戻るボタン */
.back-to-top-btn {
  position: fixed;
  bottom: 24px;
  right: 24px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--surface);
  color: var(--ink);
  border: 1px solid var(--line-strong);
  box-shadow: var(--shadow);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  font-weight: bold;
  cursor: pointer;
  z-index: 99;
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px);
  transition: var(--transition);
}

.back-to-top-btn.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top-btn:hover {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
}

/* スクロールアニメーション表示用のクラス */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease, transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* レスポンシブ幅（デスクトップ） */
@media (min-width: 760px) {
  .site-header, .hero, .section, .site-footer {
    padding-left: clamp(40px, 8vw, 120px);
    padding-right: clamp(40px, 8vw, 120px);
  }
  
  .card-grid { 
    grid-template-columns: repeat(3, 1fr); 
  }
  
  .profile-container {
    grid-template-columns: 1.2fr 1fr;
    align-items: start;
  }
  
  .profile-card {
    grid-template-columns: 140px 1fr;
    align-items: start;
  }
  
  .profile-avatar-wrapper {
    justify-content: flex-start;
  }
  
  .timeline { 
    grid-template-columns: repeat(2, 1fr); 
  }
  
  .footer-grid { 
    grid-template-columns: 1.5fr 1fr 1fr; 
    gap: 64px; 
  }
}

/* スマートフォンでのヒーロー調整 */
@media (max-width: 759px) {
  .hero {
    min-height: 80svh;
    padding-top: 60px;
    padding-bottom: 240px; /* ダイアグラム用のスペース */
  }
  
  .hero::before {
    background-image:
      linear-gradient(180deg, rgba(243, 247, 244, 0.97) 0%, rgba(243, 247, 244, 0.9) 70%, rgba(243, 247, 244, 0.4) 100%),
      url("../img/education-hero.png");
    background-position: top center;
  }
  
  .diagram {
    right: 50%;
    transform: translateX(50%);
    bottom: 40px;
    width: calc(100% - 48px);
  }
  
  .form-container {
    padding: 16px 8px;
  }
  
  .google-form {
    min-height: 520px;
  }
}