/* Base Styles */
:root {
  /* Skin and Black Color System */
  --color-primary: #E8B895; /* Warm Peachy-Tan */
  --color-primary-dark: #D2A373; /* Deeper Tan */
  --color-primary-light: #F5E6D3; /* Light Tan */
  --color-secondary: #000000; /* Pure Black */
  --color-secondary-light: #333333; /* Dark Gray */
  --color-accent: #E8B895; /* Skin tone accent */
  --color-success: #10b981;
  --color-warning: #f59e0b;
  --color-error: #ef4444;
  --color-white: #ffffff;
  --color-black: #000000;

  /* Light Theme Colors */
  --bg-primary: #fafafa;
  --bg-secondary: #ffffff;
  --bg-tertiary: #f8f9fa;
  --text-primary: #000000;
  --text-secondary: #333333;
  --text-muted: #666666;
  --border-color: #e5e5e5;
  --shadow-color: rgba(0, 0, 0, 0.1);

  /* Typography */
  --font-family: 'Inter', system-ui, -apple-system, sans-serif;
  --font-size-base: 16px;
  --line-height-body: 1.6;
  --line-height-heading: 1.2;

  /* Spacing */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 16px;
  --space-4: 24px;
  --space-5: 32px;
  --space-6: 48px;
  --space-7: 64px;
  --space-8: 96px;

  /* Borders */
  --border-radius-sm: 6px;
  --border-radius-md: 10px;
  --border-radius-lg: 16px;
  --border-width: 1px;

  /* Shadows */
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
  --shadow-xl: 0 16px 40px rgba(0, 0, 0, 0.15);

  /* Transitions */
  --transition-fast: 200ms ease;
  --transition-normal: 300ms ease;
  --transition-slow: 500ms ease;
}

/* Dark Theme */
[data-theme="dark"] {
  --bg-primary: #0a0a0a;
  --bg-secondary: #1a1a1a;
  --bg-tertiary: #2a2a2a;
  --text-primary: #ffffff;
  --text-secondary: #e5e5e5;
  --text-muted: #a0a0a0;
  --border-color: #333333;
  --shadow-color: rgba(0, 0, 0, 0.3);
}

/* Reset and Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: var(--font-size-base);
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-family);
  line-height: var(--line-height-body);
  color: var(--text-primary);
  background-color: var(--bg-primary);
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

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

a:focus {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

h1, h2, h3, h4, h5, h6 {
  line-height: var(--line-height-heading);
  margin-bottom: var(--space-3);
  font-weight: 600;
  color: var(--text-primary);
}

/* Layout */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-3);
  width: 100%;
}

section {
  margin-bottom: var(--space-6);
  scroll-margin-top: 80px;
}

/* Theme Toggle */
.theme-toggle {
  position: fixed;
  top: 20px;
  right: 20px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: none;
  background: var(--color-primary);
  color: var(--color-black);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-lg);
  transition: all var(--transition-normal);
  z-index: 1000;
}

.theme-toggle:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
  background: var(--color-primary-dark);
}

.theme-toggle .moon-icon {
  display: none;
}

[data-theme="dark"] .theme-toggle .sun-icon {
  display: none;
}

[data-theme="dark"] .theme-toggle .moon-icon {
  display: block;
}

/* Header Styles */
.site-header {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
  color: var(--color-black);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-md);
  padding: var(--space-3) 0;
  backdrop-filter: blur(10px);
}

.header-content {
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: var(--space-3);
  align-items: center;
  position: relative;
}

.back-button {
  position: absolute;
  top: 0;
  left: 0;
  display: flex;
  align-items: center;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--border-radius-sm);
  background-color: rgba(0, 0, 0, 0.15);
  transition: all var(--transition-fast);
  font-size: 0.9rem;
  font-weight: 500;
  white-space: nowrap;
  z-index: 10;
  color: var(--color-black);
  border: 1px solid rgba(0, 0, 0, 0.1);
}

.back-button:hover,
.back-button:focus {
  background-color: rgba(0, 0, 0, 0.25);
  transform: translateY(-1px);
}

.logo-container {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  justify-self: center;
  margin-left: var(--space-8);
}

.logo {
  background-color: var(--color-white);
  border-radius: var(--border-radius-md);
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-fast);
}

.logo:hover {
  transform: scale(1.05);
}

.logo-text {
  font-weight: 700;
  color: var(--color-secondary);
  font-size: 1.5rem;
  font-family: monospace;
}

.site-title h1 {
  font-size: 1.5rem;
  margin-bottom: 0;
  color: var(--color-black);
}

.site-title p {
  font-size: 0.875rem;
  opacity: 0.8;
  color: var(--color-black);
}

.search-container {
  position: relative;
  width: 100%;
  max-width: 300px;
  justify-self: end;
}

.search-icon {
  position: absolute;
  top: 50%;
  left: var(--space-3);
  transform: translateY(-50%);
  color: rgba(0, 0, 0, 0.6);
  pointer-events: none;
}

#search-input {
  width: 100%;
  padding: var(--space-2) var(--space-2) var(--space-2) var(--space-6);
  border-radius: var(--border-radius-md);
  border: 1px solid rgba(0, 0, 0, 0.2);
  background-color: rgba(255, 255, 255, 0.9);
  color: var(--color-black);
  font-size: 0.9rem;
  transition: all var(--transition-fast);
  backdrop-filter: blur(5px);
}

#search-input::placeholder {
  color: rgba(0, 0, 0, 0.6);
}

#search-input:focus {
  outline: none;
  border-color: var(--color-primary-dark);
  background-color: var(--color-white);
  box-shadow: 0 0 0 3px rgba(232, 184, 149, 0.2);
}

/* Mobile Responsive Header */
@media (max-width: 768px) {
  .header-content {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
    align-items: center;
    padding-top: var(--space-6);
  }

  .back-button {
    position: absolute;
    top: 0;
    left: 0;
    padding: var(--space-1) var(--space-2);
    font-size: 0.85rem;
  }

  .logo-container {
    margin-left: 0;
    justify-self: auto;
  }

  .search-container {
    width: 100%;
    max-width: none;
    justify-self: auto;
  }

  .theme-toggle {
    top: 15px;
    right: 15px;
    width: 40px;
    height: 40px;
  }
}

/* Introduction Section */
.intro-section {
  margin-top: var(--space-5);
}

.intro-card {
  background-color: var(--bg-secondary);
  border-radius: var(--border-radius-lg);
  padding: var(--space-5);
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
  transition: all var(--transition-normal);
}

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

.intro-card h2 {
  color: var(--text-primary);
  font-size: 1.75rem;
  margin-bottom: var(--space-3);
}

.intro-card p {
  color: var(--text-secondary);
  font-size: 1.1rem;
  line-height: 1.6;
  margin-bottom: var(--space-4);
}

.intro-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  margin-top: var(--space-4);
}

.btn {
  display: inline-flex;
  align-items: center;
  padding: var(--space-3) var(--space-4);
  border-radius: var(--border-radius-md);
  font-weight: 600;
  font-size: 0.95rem;
  transition: all var(--transition-fast);
  cursor: pointer;
  text-decoration: none;
  border: none;
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left var(--transition-normal);
}

.btn:hover::before {
  left: 100%;
}

.btn:focus {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
  color: var(--color-black);
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  background: linear-gradient(135deg, var(--color-primary-dark), var(--color-primary));
}

.btn-secondary {
  background-color: var(--bg-secondary);
  color: var(--text-primary);
  border: 2px solid var(--color-primary);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background-color: var(--color-primary);
  color: var(--color-black);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

/* Section Titles */
.section-title {
  font-size: 2rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--space-3);
  padding-bottom: var(--space-2);
  border-bottom: 3px solid var(--color-primary);
  display: inline-block;
  position: relative;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -3px;
  left: 0;
  width: 50%;
  height: 3px;
  background: var(--color-primary-dark);
  border-radius: 2px;
}

.section-description {
  color: var(--text-secondary);
  margin-bottom: var(--space-5);
  font-size: 1.1rem;
  line-height: 1.6;
}

/* Categories Section */
.categories-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-4);
}

@media (min-width: 640px) {
  .categories-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .categories-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.category-card {
  background-color: var(--bg-secondary);
  border-radius: var(--border-radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
  border: 1px solid var(--border-color);
  position: relative;
}

.category-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-primary-dark));
}

.category-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.category-header {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
  color: var(--color-black);
  padding: var(--space-4);
}

.category-header h3 {
  margin: 0;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-black);
}

.category-header p {
  margin: var(--space-2) 0 0;
  font-size: 0.9rem;
  opacity: 0.9;
  color: var(--color-black);
}

.category-body {
  padding: var(--space-4);
}

.tag-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  padding: 0;
}

.tag-item {
  width: 100%;
}

.tag-link {
  display: block;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--border-radius-sm);
  transition: all var(--transition-fast);
  border: 1px solid transparent;
}

.tag-link:hover,
.tag-link:focus {
  background-color: var(--color-primary-light);
  border-color: var(--color-primary);
  transform: translateX(4px);
}

.tag-name {
  font-family: 'Fira Code', monospace;
  color: var(--text-primary);
  font-weight: 600;
  font-size: 0.9rem;
}

/* Alphabetical Section */
.alphabetical-container {
  background-color: var(--bg-secondary);
  border-radius: var(--border-radius-lg);
  padding: var(--space-4);
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
}

.alphabetical-container .tag-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: var(--space-2);
}

.tag-element {
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--bg-tertiary);
  border-radius: var(--border-radius-sm);
  padding: var(--space-2) var(--space-3);
  font-family: 'Fira Code', monospace;
  font-weight: 600;
  color: var(--text-primary);
  transition: all var(--transition-fast);
  text-align: center;
  min-height: 44px;
  text-decoration: none;
  border: 1px solid var(--border-color);
  font-size: 0.85rem;
}

.tag-element:hover,
.tag-element:focus {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
  color: var(--color-black);
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
  border-color: var(--color-primary-dark);
}

/* Footer */
.site-footer {
  background-color: var(--color-black);
  color: var(--color-white);
  padding: var(--space-5) 0;
  margin-top: var(--space-8);
}

.footer-content {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

@media (min-width: 768px) {
  .footer-content {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }
}

.copyright p {
  font-size: 0.875rem;
  color: #cccccc;
}

.footer-links {
  display: flex;
  gap: var(--space-4);
}

.footer-links a {
  color: #cccccc;
  font-size: 0.875rem;
  transition: color var(--transition-fast);
}

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

/* Animations */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  animation: fadeIn 0.8s ease-out forwards;
}

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

.delay-100 { animation-delay: 100ms; }
.delay-200 { animation-delay: 200ms; }
.delay-300 { animation-delay: 300ms; }
.delay-400 { animation-delay: 400ms; }

/* No Results */
.no-results {
  padding: var(--space-5);
  text-align: center;
  color: var(--text-muted);
  font-style: italic;
}

/* Page Transition */
.page-transition {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
  z-index: 9999;
  transform: translateY(100%);
  transition: transform 0.5s ease-in-out;
  pointer-events: none;
  display: flex;
  align-items: center;
  justify-content: center;
}

.page-transition.active {
  transform: translateY(0);
  pointer-events: all;
}

.page-transition::before {
  content: 'Loading...';
  color: var(--color-black);
  font-size: 1.5rem;
  font-weight: 600;
}

/* Scrollbar Styling */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-tertiary);
}

::-webkit-scrollbar-thumb {
  background: var(--color-primary);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-primary-dark);
}

/* Mobile Optimizations */
@media (max-width: 480px) {
  .intro-card {
    padding: var(--space-4);
  }
  
  .section-title {
    font-size: 1.5rem;
  }
  
  .btn {
    width: 100%;
    justify-content: center;
  }
  
  .alphabetical-container .tag-list {
    grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
  }
}