/* Reset and Base Styles */
*, *::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-sans);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  min-height: 100vh;
  overflow-x: hidden;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.2;
  margin-bottom: var(--space-md);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.75rem; }
h4 { font-size: 1.5rem; }
h5 { font-size: 1.25rem; }
h6 { font-size: 1.125rem; }

p {
  margin-bottom: var(--space-md);
}

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

a:hover {
  color: var(--brand-secondary);
}

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

/* Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: var(--bg-primary);
  border-bottom: 1px solid var(--border-light);
  z-index: var(--z-sticky);
  backdrop-filter: blur(10px);
  background: rgba(var(--bg-primary-rgb, 255, 255, 255), 0.9);
}

[data-theme="dark"] .header {
  background: rgba(15, 15, 15, 0.9);
}

.header-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  flex: 0 0 auto;
}

.logo-text {
  font-size: 1.5rem;
  font-weight: 700;
  background: var(--brand-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  /* Adjust baseline for Tamil characters */
  display: inline-block;
  position: relative;
  top: -2px; /* Move text up to compensate for ஐ character */
  line-height: 1.2; /* Add some breathing room */
  padding: 4px 0; /* Add padding to prevent clipping */
  font-family: 'Noto Sans Tamil', var(--font-sans);
}

/* Navigation */
.nav {
  flex: 1 1 auto;
  display: flex;
  justify-content: center;
}

.nav-list {
  display: flex;
  list-style: none;
  gap: var(--space-xl);
  margin: 0;
  padding: 0;
  flex-wrap: wrap;
  justify-content: center;
}

.nav-link {
  color: var(--text-secondary);
  font-weight: 500;
  transition: color var(--transition-fast);
  position: relative;
}

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

.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--brand-primary);
}

/* Header Controls */
.header-controls {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  flex: 0 0 auto;
}

.search-toggle,
.theme-toggle,
.mobile-menu-toggle {
  background: none;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  padding: var(--space-sm);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.search-toggle:hover,
.theme-toggle:hover,
.mobile-menu-toggle:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

/* Language Toggle */
.lang-toggle {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-full);
  padding: var(--space-xs) var(--space-md);
  cursor: pointer;
  font-size: 0.875rem;
  font-weight: 500;
  transition: all var(--transition-fast);
}

.lang-toggle.compact {
  padding: var(--space-xs) var(--space-sm);
  min-width: auto;
  font-weight: 600;
}

.lang-toggle:hover {
  background: var(--bg-hover);
  border-color: var(--border-color);
}

.lang-toggle.compact:hover {
  background: var(--brand-primary);
  border-color: var(--brand-primary);
  color: white;
}

.lang-toggle.compact:hover .lang-current,
.lang-toggle.compact:hover .lang-separator,
.lang-toggle.compact:hover .lang-switch {
  color: white;
}

.lang-current {
  color: var(--brand-primary);
  font-weight: 700;
  /* Fix Tamil baseline alignment */
  display: inline-block;
  line-height: 1;
  vertical-align: middle;
  position: relative;
}

/* Specific adjustment for Tamil characters in toggle */
.lang-toggle.compact .lang-current,
.lang-toggle.compact .lang-switch {
  font-size: 1rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 1.5em;
  height: 1.4em;
}

/* When showing Tamil character, adjust baseline */
.lang-toggle.compact .tamil-char {
  position: relative;
  top: -1px; /* Very slight upward adjustment */
  font-family: 'Noto Sans Tamil', var(--font-sans);
}

/* Fine-tune based on content */
.lang-toggle.compact {
  font-family: var(--font-sans), 'Noto Sans Tamil', sans-serif;
  letter-spacing: 0;
}

.lang-separator {
  color: var(--text-tertiary);
  margin: 0 2px;
  vertical-align: middle;
}

.lang-switch {
  color: var(--text-secondary);
  /* Fix Tamil baseline alignment */
  display: inline-block;
  line-height: 1;
  vertical-align: middle;
  position: relative;
}

/* Theme Toggle Icons */
.theme-toggle .moon-icon {
  display: none;
}

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

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

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
}

/* Search Overlay */
.search-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.8);
  z-index: var(--z-modal);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
}

.search-overlay.active {
  opacity: 1;
  visibility: visible;
}

.search-container {
  width: 90%;
  max-width: 600px;
  position: relative;
}

.search-input {
  width: 100%;
  padding: var(--space-lg) var(--space-xl);
  font-size: 1.25rem;
  background: var(--bg-primary);
  border: 2px solid var(--border-color);
  border-radius: var(--radius-xl);
  color: var(--text-primary);
  outline: none;
}

.search-input:focus {
  border-color: var(--brand-primary);
}

.search-close {
  position: absolute;
  right: var(--space-lg);
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  color: var(--text-tertiary);
  cursor: pointer;
  padding: var(--space-sm);
}

/* Main Content */
.main {
  margin-top: 64px;
  min-height: calc(100vh - 64px);
}

/* Hero Section */
.hero {
  padding: var(--space-3xl) 0;
  background: var(--bg-secondary);
  position: relative;
  overflow: hidden;
}

.hero-content {
  text-align: center;
  position: relative;
  z-index: 1;
}

.hero-title {
  font-size: 3rem;
  font-weight: 700;
  margin-bottom: var(--space-lg);
  background: var(--brand-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-2xl);
}

.hero-actions {
  display: flex;
  gap: var(--space-md);
  justify-content: center;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  padding: var(--space-md) var(--space-xl);
  font-weight: 600;
  border-radius: var(--radius-lg);
  transition: all var(--transition-fast);
  cursor: pointer;
  border: none;
  font-size: 1rem;
}

.btn-primary {
  background: var(--brand-primary);
  color: white;
}

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

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

.btn-secondary:hover {
  background: var(--bg-hover);
  border-color: var(--brand-primary);
}

/* AI Animation */
.hero-visual {
  position: absolute;
  top: 0;
  right: 0;
  width: 50%;
  height: 100%;
  opacity: 1.0;
}

.ai-animation {
  position: relative;
  width: 100%;
  height: 100%;
}

.ai-particle {
  position: absolute;
  width: 4px;
  height: 4px;
  background: var(--brand-primary);
  border-radius: 50%;
  animation: float 6s infinite ease-in-out;
}

.ai-particle:nth-child(1) { top: 20%; left: 20%; animation-delay: 0s; }
.ai-particle:nth-child(2) { top: 40%; left: 60%; animation-delay: 1s; }
.ai-particle:nth-child(3) { top: 60%; left: 30%; animation-delay: 2s; }
.ai-particle:nth-child(4) { top: 80%; left: 70%; animation-delay: 3s; }

@keyframes float {
  0%, 100% { transform: translateY(0) scale(1); }
  50% { transform: translateY(-20px) scale(1.2); }
}

/* Sections */
.section {
  padding: var(--space-3xl) 0;
}

.section-title {
  text-align: center;
  margin-bottom: var(--space-2xl);
}

.section-footer {
  text-align: center;
  margin-top: var(--space-2xl);
}

.view-all-link {
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
}

/* Grids */
.models-grid,
.tools-grid,
.news-grid {
  display: grid;
  gap: var(--space-lg);
}

.models-grid {
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
}

.tools-grid {
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
}

.news-grid {
  grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
}

/* Cards */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-xl);
  padding: var(--space-lg);
  transition: all var(--transition-base);
  cursor: pointer;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
  border-color: var(--brand-primary);
}

/* Footer */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-light);
  padding: var(--space-2xl) 0;
  margin-top: var(--space-3xl);
}

.footer-content {
  text-align: center;
}

.footer-logo {
  font-size: 1.25rem;
  font-weight: 700;
  background: var(--brand-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  /* Same baseline adjustment as header logo */
  display: inline-block;
  position: relative;
  top: -2px; /* Match header logo positioning */
  line-height: 1.2; /* Add some breathing room */
  padding: 4px 0; /* Add padding to prevent clipping */
  font-family: 'Noto Sans Tamil', var(--font-sans);
}

.footer-tagline {
  color: var(--text-secondary);
  margin-top: var(--space-sm);
}

.footer-links {
  display: flex;
  gap: var(--space-xl);
  justify-content: center;
  margin: var(--space-xl) 0;
}

.footer-links a {
  color: var(--text-secondary);
}

.footer-copyright {
  color: var(--text-tertiary);
  font-size: 0.875rem;
}

/* Mobile Navigation */
.mobile-nav {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: var(--bg-primary);
  border-top: 1px solid var(--border-light);
  z-index: var(--z-sticky);
}

.mobile-nav-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-sm);
  color: var(--text-tertiary);
  font-size: 0.75rem;
}

.mobile-nav-item.active {
  color: var(--brand-primary);
}

/* Loading States */
.loading {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-2xl);
}

.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--border-light);
  border-top-color: var(--brand-primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Utility Classes */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}