/* --- CSS Variables & Reset --- */
:root {
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  --accent-green: #059669;
  --accent-green-light: #ecfdf5;
  --accent-purple: #7c3aed;
  --accent-purple-light: #f5f3ff;
  --accent-amber: #d97706;
  --accent-amber-light: #fffbeb;
  --accent-cyan: #0891b2;
  --accent-cyan-light: #ecfeff;
  --text-main: #1e293b;
  --text-muted: #475569;
  --bg-body: #f8fafc;
  --bg-card: #ffffff;
  --border: #e2e8f0;
  --border-focus: #94a3b8;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 12px 28px -6px rgba(0, 0, 0, 0.1);
  --font-family: 'Inter', 'Noto Sans JP', -apple-system, BlinkMacSystemFont, sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-body);
  color: var(--text-main);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

code {
  font-family: Consolas, Monaco, 'Andale Mono', monospace;
  background-color: #f1f5f9;
  color: #0f172a;
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.88em;
  border: 1px solid #e2e8f0;
}

/* --- Container & Utilities --- */
.container {
  width: 100%;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 84px 0;
}

.section-header {
  margin-bottom: 44px;
}

.section-badge {
  display: inline-block;
  padding: 5px 14px;
  background-color: #dbeafe;
  color: #1e40af;
  font-size: 0.85rem;
  font-weight: 700;
  border-radius: 9999px;
  margin-bottom: 12px;
}

.step-badge {
  display: inline-block;
  padding: 6px 16px;
  font-size: 0.85rem;
  font-weight: 700;
  border-radius: 9999px;
  margin-bottom: 14px;
  letter-spacing: 0.02em;
}

.prep-badge {
  background-color: var(--accent-amber-light);
  color: var(--accent-amber);
  border: 1px solid #fde68a;
}

.basic-badge {
  background-color: var(--accent-green-light);
  color: var(--accent-green);
  border: 1px solid #a7f3d0;
}

.api-badge {
  background-color: var(--accent-cyan-light);
  color: var(--accent-cyan);
  border: 1px solid #a5f3fc;
}

.advanced-badge {
  background-color: var(--accent-purple-light);
  color: var(--accent-purple);
  border: 1px solid #ddd6fe;
}

.section-title {
  font-size: 2.15rem;
  font-weight: 800;
  margin-bottom: 14px;
  letter-spacing: -0.02em;
  line-height: 1.3;
}

.section-description {
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 860px;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 24px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: all 0.2s ease;
  cursor: pointer;
  border: 1px solid transparent;
}

.btn-primary {
  background-color: var(--primary);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.25);
}

.btn-primary:hover {
  background-color: var(--primary-hover);
  transform: translateY(-1px);
}

.btn-secondary {
  background-color: #ffffff;
  color: var(--text-main);
  border-color: var(--border);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background-color: #f1f5f9;
  border-color: var(--border-focus);
}

/* --- Header / Nav --- */
.site-header {
  position: sticky;
  top: 0;
  background-color: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  z-index: 100;
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.3rem;
  font-weight: 800;
  text-decoration: none;
  color: var(--text-main);
  letter-spacing: -0.03em;
}

.nav-logo-img {
  width: 36px;
  height: 36px;
  object-fit: contain;
}

.logo-accent {
  color: var(--primary);
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 20px;
}

.nav-menu a {
  text-decoration: none;
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 600;
  transition: color 0.2s;
}

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

.lang-btn {
  display: flex;
  align-items: center;
  gap: 8px;
  background: #ffffff;
  border: 1px solid var(--border);
  padding: 6px 14px;
  border-radius: 9999px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-main);
  cursor: pointer;
  transition: all 0.2s ease;
}

.lang-code {
  font-size: 0.72rem;
  font-weight: 800;
  background: #eff6ff;
  color: var(--primary);
  padding: 2px 6px;
  border-radius: 4px;
}

.lang-btn:hover {
  background: #f1f5f9;
  border-color: var(--border-focus);
}

/* --- Hero Section --- */
.hero-section {
  padding: 84px 0 56px;
  text-align: center;
  background: linear-gradient(180deg, #ffffff 0%, var(--bg-body) 100%);
}

.hero-badge {
  display: inline-block;
  padding: 6px 16px;
  background-color: #eff6ff;
  border: 1px solid #bfdbfe;
  color: #1d4ed8;
  font-size: 0.85rem;
  font-weight: 700;
  border-radius: 9999px;
  margin-bottom: 20px;
}

.hero-title {
  font-size: 2.85rem;
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.03em;
  margin-bottom: 22px;
}

.hero-subtitle {
  font-size: 1.15rem;
  color: var(--text-muted);
  max-width: 720px;
  margin: 0 auto 34px;
  line-height: 1.75;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

/* --- Ad Box Styling --- */
.ad-wrapper {
  margin: 16px auto;
  text-align: center;
}

.ad-label {
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  color: #94a3b8;
  margin-bottom: 6px;
}

.ad-box {
  background: #ffffff;
  border: 1px dashed #cbd5e1;
  border-radius: var(--radius-sm);
  min-height: 96px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  padding: 8px;
}

/* --- SecreAI 4 Pillars Grid --- */
.pillars-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-bottom: 48px;
}

.pillar-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 28px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s, box-shadow 0.2s;
}

.pillar-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.highlight-pillar {
  border: 2px solid #93c5fd;
  background: linear-gradient(145deg, #ffffff 0%, #f8fbff 100%);
}

.pillar-num {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  color: var(--primary);
  background: var(--primary-light);
  padding: 3px 10px;
  border-radius: 4px;
  margin-bottom: 12px;
}

.pillar-card h3 {
  font-size: 1.22rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--text-main);
}

.pillar-card p {
  font-size: 0.96rem;
  color: var(--text-muted);
  line-height: 1.65;
}

/* --- Main Hub Showcase --- */
.hub-showcase {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 40px;
  box-shadow: var(--shadow-md);
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 36px;
  align-items: center;
}

.hub-showcase-text h3 {
  font-size: 1.45rem;
  font-weight: 800;
  margin-bottom: 14px;
}

.hub-showcase-text p {
  font-size: 0.98rem;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.hub-points {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 28px;
  font-size: 0.95rem;
}

.hub-points li {
  position: relative;
  padding-left: 16px;
  border-left: 3px solid var(--primary);
}

.featured-actions {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.hub-showcase-img {
  text-align: center;
}

.screenshot-img {
  width: 100%;
  height: auto;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-md);
  cursor: zoom-in;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.screenshot-img:hover {
  transform: scale(1.015);
  box-shadow: var(--shadow-lg);
}

.img-caption {
  display: block;
  font-size: 0.8rem;
  color: #64748b;
  margin-top: 8px;
}

/* --- Preparation / Prerequisites Section --- */
.prep-section {
  background-color: #ffffff;
  border-top: 1px solid var(--border);
}

.prep-columns {
  display: grid;
  grid-template-columns: 1fr 1.25fr;
  gap: 32px;
}

.prep-group {
  background: var(--bg-body);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 28px;
}

.prep-group-title {
  font-size: 1.22rem;
  font-weight: 800;
  margin-bottom: 8px;
  color: var(--text-main);
}

.prep-group-sub {
  font-size: 0.92rem;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.prep-cards {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.prep-card {
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 20px;
  box-shadow: var(--shadow-sm);
}

.prep-card.req-card {
  border-left: 4px solid var(--primary);
}

.prep-card-top {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 8px;
}

.prep-card-top h4 {
  font-size: 1.08rem;
  font-weight: 700;
}

.status-tag {
  font-size: 0.72rem;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 4px;
}

.tag-required {
  background-color: #dbeafe;
  color: #1e40af;
}

.tag-rec {
  background-color: #d1fae5;
  color: #065f46;
}

.tag-optional {
  background-color: #f1f5f9;
  color: #475569;
}

.prep-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 12px;
  line-height: 1.55;
}

.prep-link {
  display: inline-flex;
  align-items: center;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
}

.prep-link:hover {
  color: var(--primary-hover);
  text-decoration: underline;
}

.prep-multi-links {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
}

/* --- Basic Guide Section (Step 1-2-3) --- */
.guide-basic-section {
  background-color: var(--bg-body);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.basic-steps-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.step-card {
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  display: flex;
  flex-direction: column;
  position: relative;
  box-shadow: var(--shadow-sm);
}

.step-number {
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.05em;
  color: var(--accent-green);
  background: var(--accent-green-light);
  border: 1px solid #a7f3d0;
  align-self: flex-start;
  padding: 4px 10px;
  border-radius: 6px;
  margin-bottom: 14px;
}

.step-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.step-card p {
  font-size: 0.93rem;
  color: var(--text-muted);
  margin-bottom: 20px;
  flex-grow: 1;
}

.step-img-box {
  margin-top: auto;
}

.step-img-box .screenshot-img {
  max-height: 360px;
  object-fit: contain;
  background: #f1f5f9;
}

/* --- API Endpoints Section & Table --- */
.api-section {
  background-color: #ffffff;
  border-bottom: 1px solid var(--border);
}

.api-table-wrapper {
  overflow-x: auto;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

.api-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.92rem;
}

.api-table th {
  background-color: #f8fafc;
  color: var(--text-main);
  font-weight: 700;
  padding: 14px 18px;
  border-bottom: 2px solid var(--border);
  white-space: nowrap;
}

.api-table td {
  padding: 13px 18px;
  border-bottom: 1px solid var(--border);
  vertical-align: middle;
}

.api-table tr:last-child td {
  border-bottom: none;
}

.api-table tr:hover {
  background-color: #f8fafc;
}

.method-tag {
  font-size: 0.72rem;
  font-weight: 800;
  background: #dbeafe;
  color: #1e40af;
  padding: 2px 7px;
  border-radius: 4px;
}

/* --- Advanced Guide Section (Interactive Tabs) --- */
.guide-advanced-section {
  background-color: var(--bg-body);
  border-bottom: 1px solid var(--border);
}

.adv-tabs-container {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  overflow: hidden;
}

.adv-tabs-nav {
  display: flex;
  flex-wrap: wrap;
  background: #f1f5f9;
  border-bottom: 1px solid var(--border);
  padding: 8px 8px 0;
  gap: 6px;
}

.adv-tab-btn {
  padding: 12px 20px;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-muted);
  background: transparent;
  border: 1px solid transparent;
  border-bottom: none;
  border-radius: 10px 10px 0 0;
  cursor: pointer;
  transition: all 0.15s ease;
  font-family: inherit;
}

.adv-tab-btn:hover {
  color: var(--text-main);
  background: rgba(255, 255, 255, 0.6);
}

.adv-tab-btn.active {
  background: #ffffff;
  color: var(--accent-purple);
  border-color: var(--border);
  position: relative;
  top: 1px;
}

.adv-tabs-content {
  padding: 36px;
}

.adv-tab-pane {
  display: none;
}

.adv-tab-pane.active {
  display: block;
  animation: fadeIn 0.25s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: translateY(0); }
}

.adv-pane-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 36px;
  align-items: center;
}

.adv-usecase-tag {
  display: inline-block;
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--accent-purple);
  background: var(--accent-purple-light);
  padding: 4px 12px;
  border-radius: 6px;
  margin-bottom: 12px;
}

.adv-pane-info h3 {
  font-size: 1.45rem;
  font-weight: 800;
  margin-bottom: 12px;
}

.adv-pane-info p {
  font-size: 0.98rem;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.adv-feature-points {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.adv-feature-points li {
  font-size: 0.95rem;
  color: var(--text-main);
  padding-left: 16px;
  border-left: 3px solid #c4b5fd;
  line-height: 1.6;
}

.adv-pane-img {
  text-align: center;
}

.adv-pane-img .screenshot-img {
  max-height: 460px;
  width: auto;
  max-width: 100%;
  object-fit: contain;
}

/* --- Tools Grid --- */
.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(330px, 1fr));
  gap: 24px;
}

.tool-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 28px;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-sm);
  transition: all 0.2s ease;
}

.tool-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--border-focus);
}

.tool-card-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 14px;
}

.tool-icon {
  width: 52px;
  height: 52px;
  object-fit: contain;
  border-radius: 10px;
  flex-shrink: 0;
}

.extension-icon-badge {
  width: 52px;
  height: 52px;
  background: linear-gradient(135deg, #fef3c7 0%, #fde68a 100%);
  color: #b45309;
  font-weight: 800;
  font-size: 1.1rem;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid #fcd34d;
  flex-shrink: 0;
}

.tool-type-badge {
  align-self: flex-start;
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 9999px;
  background-color: #f1f5f9;
  color: #475569;
  margin-bottom: 6px;
}

.chrome-card .chrome-badge {
  background-color: #fef3c7;
  color: #b45309;
}

.tool-name {
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1.2;
}

.tool-desc {
  font-size: 0.94rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 18px;
  flex-grow: 1;
}

.tool-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 18px;
}

.tool-tags span {
  font-size: 0.75rem;
  background: #f8fafc;
  border: 1px solid var(--border);
  padding: 2px 8px;
  border-radius: 4px;
  color: #64748b;
}

.tool-footer {
  border-top: 1px solid var(--border);
  padding-top: 14px;
}

.tool-link {
  font-size: 0.94rem;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.tool-link:hover {
  color: var(--primary-hover);
  text-decoration: underline;
}

/* --- Contact Section --- */
.contact-section {
  text-align: center;
  background-color: #ffffff;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.contact-container .section-description {
  margin: 0 auto 28px;
}

/* --- Footer --- */
.site-footer {
  background-color: #ffffff;
  padding: 40px 0;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.footer-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
  text-align: center;
}

.footer-title {
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--text-main);
}

.footer-sub {
  font-size: 0.85rem;
  color: #94a3b8;
}

.footer-links {
  display: flex;
  gap: 20px;
}

.footer-links a {
  color: var(--text-muted);
  text-decoration: none;
}

.footer-links a:hover {
  color: var(--primary);
  text-decoration: underline;
}

.footer-copy {
  font-size: 0.8rem;
  color: #94a3b8;
  margin-top: 6px;
}

/* --- Modal & Lightbox Styling --- */
.modal {
  display: none;
  position: fixed;
  z-index: 1000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(15, 23, 42, 0.72);
  backdrop-filter: blur(4px);
  overflow-y: auto;
}

.modal-content {
  background-color: #ffffff;
  margin: 80px auto;
  padding: 36px;
  border-radius: var(--radius-md);
  max-width: 680px;
  position: relative;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
  line-height: 1.7;
}

.modal-content h2 {
  margin-bottom: 16px;
  font-size: 1.4rem;
}

.modal-content h3 {
  margin: 18px 0 8px;
  font-size: 1.1rem;
}

.modal-content p {
  color: #475569;
  font-size: 0.95rem;
  margin-bottom: 12px;
}

.modal-close {
  position: absolute;
  top: 18px;
  right: 22px;
  font-size: 28px;
  font-weight: 700;
  color: #94a3b8;
  cursor: pointer;
}

.modal-close:hover {
  color: var(--text-main);
}

/* Image Lightbox */
.image-lightbox {
  text-align: center;
  padding: 40px 20px;
}

.lightbox-close {
  color: #ffffff;
  font-size: 38px;
  top: 20px;
  right: 32px;
}

.lightbox-img {
  max-width: 92%;
  max-height: 82vh;
  border-radius: var(--radius-sm);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
  margin-top: 20px;
}

.lightbox-caption {
  color: #e2e8f0;
  margin-top: 14px;
  font-size: 0.95rem;
}

/* --- Responsive Layout --- */
@media (max-width: 960px) {
  .pillars-grid,
  .prep-columns,
  .basic-steps-grid,
  .hub-showcase,
  .adv-pane-grid {
    grid-template-columns: 1fr;
  }
  .hero-title {
    font-size: 2.1rem;
  }
  .hub-showcase,
  .adv-tabs-content {
    padding: 24px;
  }
  .nav-menu a {
    display: none;
  }
}