/* ============================================================
   API Compass - Design System
   Japanese API Catalog Site
   ============================================================ */

/* --- CSS Custom Properties --- */
:root {
  /* Background */
  --bg-main: #0a0e1a;
  --bg-card: #111827;
  --bg-secondary: #1a2035;
  --bg-glass: rgba(17, 24, 39, 0.7);

  /* Brand Colors */
  --color-primary: #3b82f6;
  --color-primary-hover: #2563eb;
  --color-primary-light: rgba(59, 130, 246, 0.15);
  --color-secondary: #8b5cf6;
  --color-secondary-hover: #7c3aed;
  --color-secondary-light: rgba(139, 92, 246, 0.15);
  --color-accent: #06b6d4;
  --color-accent-light: rgba(6, 182, 212, 0.15);

  /* Semantic Colors */
  --color-success: #10b981;
  --color-success-light: rgba(16, 185, 129, 0.15);
  --color-warning: #f59e0b;
  --color-warning-light: rgba(245, 158, 11, 0.15);

  /* Text */
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;

  /* Border */
  --border-color: #1e293b;
  --border-hover: rgba(255, 255, 255, 0.12);

  /* Misc */
  --radius: 14px;
  --radius-sm: 8px;
  --radius-pill: 9999px;
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.25);
  --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.35);
  --transition: 0.2s ease;
  --header-height: 64px;

  /* Typography */
  --font-family: system-ui, -apple-system, 'Noto Sans JP', sans-serif;
  --line-height-ja: 1.8;
}

/* --- Light Theme --- */
[data-theme="light"] {
  --bg-main: #f5f7fa;
  --bg-card: #ffffff;
  --bg-secondary: #eef1f6;
  --bg-glass: rgba(255, 255, 255, 0.8);
  --text-primary: #1a1a2e;
  --text-secondary: #4a5568;
  --text-muted: #718096;
  --border-color: #e0e0e0;
  --border-hover: rgba(0, 0, 0, 0.12);
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.12);
  --color-primary-light: rgba(59, 130, 246, 0.1);
  --color-secondary-light: rgba(139, 92, 246, 0.1);
  --color-accent-light: rgba(6, 182, 212, 0.1);
  --color-success-light: rgba(16, 185, 129, 0.1);
  --color-warning-light: rgba(245, 158, 11, 0.1);
}

[data-theme="light"] .site-header {
  background: rgba(245, 247, 250, 0.85);
}

[data-theme="light"] .hero__title {
  background: linear-gradient(135deg, #1a1a2e 0%, var(--color-primary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

[data-theme="light"] .tag {
  background: rgba(0, 0, 0, 0.05);
}

[data-theme="light"] .popularity-badge .score-bar {
  background: rgba(0, 0, 0, 0.1);
}

[data-theme="light"] .ranking-score__bar {
  background: rgba(0, 0, 0, 0.08);
}

[data-theme="light"] .modal__score-bar {
  background: rgba(0, 0, 0, 0.08);
}

[data-theme="light"] .modal-overlay {
  background: rgba(0, 0, 0, 0.4);
}


/* --- Reset & Base --- */

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 16px);
}

body {
  font-family: var(--font-family);
  font-weight: 400;
  background: var(--bg-main);
  color: var(--text-primary);
  line-height: var(--line-height-ja);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color 0.3s ease, color 0.3s ease;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition);
}

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

img {
  max-width: 100%;
  display: block;
}


/* --- Typography --- */

h1, h2, h3, h4, h5, h6 {
  color: var(--text-primary);
  font-weight: 700;
  line-height: 1.3;
}

h1 { font-size: 2.25rem; }
h2 { font-size: 1.75rem; }
h3 { font-size: 1.25rem; }

p {
  color: var(--text-secondary);
  line-height: var(--line-height-ja);
}


/* --- Layout --- */

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 24px;
}

.flex {
  display: flex;
  align-items: center;
  gap: 12px;
}

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

.flex--wrap {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.flex--col {
  display: flex;
  flex-direction: column;
  gap: 12px;
}


/* --- Site Header --- */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--header-height);
  background: rgba(10, 14, 26, 0.8);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-color);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.site-header__logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 8px;
}

.site-header__logo span {
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.site-header__nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-link {
  color: var(--text-secondary);
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 500;
  transition: color var(--transition), background var(--transition);
}

.nav-link:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.05);
}

.nav-link.active {
  color: var(--color-primary);
  background: var(--color-primary-light);
}


/* --- Hero Section --- */

.hero {
  position: relative;
  padding: calc(var(--header-height) + 64px) 0 64px;
  text-align: center;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 500px;
  background: radial-gradient(
    ellipse at center,
    rgba(59, 130, 246, 0.12) 0%,
    rgba(139, 92, 246, 0.06) 40%,
    transparent 70%
  );
  pointer-events: none;
}

.hero__title {
  font-size: 2.75rem;
  font-weight: 800;
  margin-bottom: 16px;
  background: linear-gradient(135deg, var(--text-primary) 0%, var(--color-primary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero__subtitle {
  font-size: 1.15rem;
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto 40px;
}


/* --- Sections --- */

.section {
  padding: 64px 0;
}

.section__title {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 32px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.section__title::before {
  content: '';
  display: inline-block;
  width: 4px;
  height: 28px;
  background: linear-gradient(180deg, var(--color-primary), var(--color-secondary));
  border-radius: 2px;
}


/* --- Search Bar --- */

.search-bar {
  position: relative;
  max-width: 640px;
  margin: 0 auto;
}

.search-bar__input {
  width: 100%;
  padding: 16px 20px 16px 52px;
  font-size: 1rem;
  font-family: var(--font-family);
  color: var(--text-primary);
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.search-bar__input::placeholder {
  color: var(--text-muted);
}

.search-bar__input:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-light);
}

.search-bar__icon {
  position: absolute;
  left: 18px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  pointer-events: none;
}


/* --- Filter --- */

.filter-group {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 24px 0;
}

.filter-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  font-size: 0.85rem;
  font-family: var(--font-family);
  font-weight: 500;
  color: var(--text-secondary);
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-pill);
  cursor: pointer;
  transition: all var(--transition);
  user-select: none;
}

.filter-chip:hover {
  color: var(--text-primary);
  border-color: var(--border-hover);
  background: var(--bg-secondary);
}

.filter-chip.active {
  color: var(--color-primary);
  background: var(--color-primary-light);
  border-color: var(--color-primary);
}


/* --- API Card --- */

.api-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
  display: flex;
  flex-direction: column;
}

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

.api-card__header {
  padding: 20px 20px 0;
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
}

.api-card__header h3 {
  font-size: 1.1rem;
  font-weight: 600;
}

.api-card__header h3 a {
  color: var(--text-primary);
}

.api-card__header h3 a:hover {
  color: var(--color-primary);
}

.api-card__body {
  padding: 12px 20px 20px;
  flex: 1;
}

.api-card__body p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.api-card__tags {
  padding: 0 20px 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: auto;
}


/* --- Tags & Badges --- */

.tag {
  display: inline-flex;
  align-items: center;
  padding: 3px 10px;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: var(--radius-pill);
  background: rgba(255, 255, 255, 0.06);
  color: var(--text-secondary);
  letter-spacing: 0.3px;
}

.tag--free {
  color: var(--color-success);
  background: var(--color-success-light);
}

.tag--paid {
  color: var(--color-warning);
  background: var(--color-warning-light);
}

.tag--freemium {
  color: var(--color-primary);
  background: var(--color-primary-light);
}

.category-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-accent);
  background: var(--color-accent-light);
  border-radius: var(--radius-sm);
}


/* --- Buttons --- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 24px;
  font-size: 0.9rem;
  font-family: var(--font-family);
  font-weight: 600;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
  white-space: nowrap;
}

.btn--primary {
  color: #fff;
  background: var(--color-primary);
  border-color: var(--color-primary);
}

.btn--primary:hover {
  background: var(--color-primary-hover);
  border-color: var(--color-primary-hover);
  color: #fff;
}

.btn--ghost {
  color: var(--text-secondary);
  background: transparent;
  border-color: var(--border-color);
}

.btn--ghost:hover {
  color: var(--text-primary);
  border-color: var(--border-hover);
  background: rgba(255, 255, 255, 0.04);
}


/* --- Stats Bar --- */

.stats-bar {
  display: flex;
  justify-content: center;
  gap: 48px;
  padding: 32px 0;
}

.stat-item {
  text-align: center;
}

.stat-item__value {
  font-size: 2rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.stat-item__label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: 4px;
}


/* --- Site Footer --- */

.site-footer {
  border-top: 1px solid var(--border-color);
  padding: 48px 0 32px;
  margin-top: 64px;
}

.site-footer__inner {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 40px;
}

.site-footer__brand {
  font-weight: 700;
  font-size: 1rem;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.site-footer__text {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.site-footer__links {
  display: flex;
  gap: 24px;
}

.site-footer__links a {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.site-footer__links a:hover {
  color: var(--text-primary);
}

.site-footer__copyright {
  text-align: center;
  padding-top: 32px;
  margin-top: 32px;
  border-top: 1px solid var(--border-color);
  font-size: 0.8rem;
  color: var(--text-muted);
}


/* --- Keyframe Animations --- */

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in {
  animation: fadeIn 0.5s ease forwards;
}

.slide-up {
  animation: slideUp 0.5s ease forwards;
}

.stagger-1 { animation-delay: 0.05s; }
.stagger-2 { animation-delay: 0.1s; }
.stagger-3 { animation-delay: 0.15s; }
.stagger-4 { animation-delay: 0.2s; }
.stagger-5 { animation-delay: 0.25s; }
.stagger-6 { animation-delay: 0.3s; }


/* --- Utility Classes --- */

.text-center { text-align: center; }
.text-sm { font-size: 0.85rem; }
.text-muted { color: var(--text-secondary); }
.mt-8 { margin-top: 8px; }
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mt-32 { margin-top: 32px; }
.mb-8 { margin-bottom: 8px; }
.mb-16 { margin-bottom: 16px; }
.mb-24 { margin-bottom: 24px; }
.gap-8 { gap: 8px; }
.gap-16 { gap: 16px; }
.gap-24 { gap: 24px; }


/* --- Responsive: Tablet (768px - 1024px) --- */

@media (max-width: 1024px) {
  .container {
    padding: 0 20px;
  }

  .grid {
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
  }

  .hero__title {
    font-size: 2.25rem;
  }

  .stats-bar {
    gap: 32px;
  }

  .site-footer__inner {
    flex-direction: column;
    gap: 24px;
  }
}


/* --- Responsive: Mobile (< 768px) --- */

@media (max-width: 768px) {
  :root {
    --header-height: 56px;
  }

  .container {
    padding: 0 16px;
  }

  .grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .hero {
    padding: calc(var(--header-height) + 40px) 0 40px;
  }

  .hero__title {
    font-size: 1.75rem;
  }

  .hero__subtitle {
    font-size: 1rem;
    margin-bottom: 32px;
  }

  .section {
    padding: 40px 0;
  }

  .section__title {
    font-size: 1.35rem;
    margin-bottom: 24px;
  }

  .site-header__nav {
    display: none;
  }

  .mobile-menu-btn {
    display: block;
  }

  .search-bar__input {
    padding: 14px 16px 14px 44px;
    font-size: 0.95rem;
  }

  .stats-bar {
    flex-wrap: wrap;
    gap: 24px;
    justify-content: center;
  }

  .stat-item__value {
    font-size: 1.5rem;
  }

  .filter-group {
    overflow-x: auto;
    flex-wrap: nowrap;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    margin: 16px -16px;
    padding: 0 16px;
  }

  .filter-group::-webkit-scrollbar {
    display: none;
  }

  .filter-chip {
    flex-shrink: 0;
  }

  .site-footer__links {
    flex-direction: column;
    gap: 12px;
  }

  h1 { font-size: 1.75rem; }
  h2 { font-size: 1.35rem; }
}


/* --- Theme Toggle --- */

.site-header__actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.theme-toggle {
  background: none;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-pill);
  padding: 6px 12px;
  font-size: 1.1rem;
  cursor: pointer;
  color: var(--text-secondary);
  transition: all var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
  line-height: 1;
}

.theme-toggle:hover {
  border-color: var(--border-hover);
  color: var(--text-primary);
  background: var(--bg-secondary);
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: var(--text-secondary);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 4px;
}


/* --- Autocomplete --- */

.search-bar {
  position: relative;
}

.autocomplete-list {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  margin-top: 4px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-lg);
  z-index: 50;
  max-height: 320px;
  overflow-y: auto;
  display: none;
}

.autocomplete-list.visible {
  display: block;
}

.autocomplete-item {
  padding: 10px 16px;
  font-size: 0.9rem;
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 10px;
  transition: background var(--transition), color var(--transition);
  border-bottom: 1px solid var(--border-color);
}

.autocomplete-item:last-child {
  border-bottom: none;
}

.autocomplete-item:hover,
.autocomplete-item.active {
  background: var(--color-primary-light);
  color: var(--text-primary);
}

.autocomplete-item__name {
  font-weight: 600;
  color: var(--text-primary);
}

.autocomplete-item__name-ja {
  font-size: 0.8rem;
  color: var(--text-muted);
}


/* --- Favorite Button --- */

.favorite-btn {
  background: none;
  border: none;
  font-size: 1.2rem;
  cursor: pointer;
  padding: 2px;
  line-height: 1;
  color: var(--text-muted);
  transition: all var(--transition);
  flex-shrink: 0;
}

.favorite-btn:hover {
  transform: scale(1.2);
}

.favorite-btn.favorited {
  color: #ef4444;
}

.favorite-filter-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  font-size: 0.78rem;
  font-weight: 500;
  font-family: var(--font-family);
  border-radius: var(--radius-pill);
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition);
}

.favorite-filter-btn:hover {
  border-color: var(--border-hover);
  color: var(--text-primary);
}

.favorite-filter-btn.active {
  color: #ef4444;
  background: rgba(239, 68, 68, 0.1);
  border-color: #ef4444;
}

.favorite-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 18px;
  height: 18px;
  padding: 0 5px;
  font-size: 0.7rem;
  font-weight: 700;
  color: #fff;
  background: #ef4444;
  border-radius: var(--radius-pill);
}


/* --- Affiliate Disclosure --- */

.affiliate-disclosure {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-align: center;
  margin-top: 12px;
  opacity: 0.7;
}


/* --- Premium Report CTA --- */

.premium-report-cta {
  background: linear-gradient(135deg, rgba(139, 92, 246, 0.06) 0%, rgba(59, 130, 246, 0.06) 100%);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 40px 32px;
  text-align: center;
}

.premium-report-cta h3 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.premium-report-cta p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  max-width: 520px;
  margin: 0 auto 8px;
  line-height: 1.7;
}

.premium-report-cta .cta-note {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.cta-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  font-size: 0.9rem;
  font-weight: 600;
  font-family: var(--font-family);
  color: #fff;
  background: linear-gradient(135deg, var(--color-secondary), var(--color-primary));
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  text-decoration: none;
  transition: all var(--transition);
}

.cta-btn:hover {
  opacity: 0.9;
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(139, 92, 246, 0.3);
  color: #fff;
}

[data-theme="light"] .premium-report-cta {
  background: linear-gradient(135deg, rgba(139, 92, 246, 0.05) 0%, rgba(59, 130, 246, 0.05) 100%);
}

@media (max-width: 768px) {
  .premium-report-cta {
    padding: 28px 20px;
  }

  .premium-report-cta h3 {
    font-size: 1.1rem;
  }
}


/* --- Smooth transitions for theme switch --- */

.site-header,
.api-card,
.ranking-item,
.modal,
.search-bar__input,
.filter-chip,
.sort-btn,
.category-nav__item,
.about-section,
.premium-report-cta,
.site-footer {
  transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}