/* SkillUnlock Mobile Modern CSS - Optimized for Performance */

:root {
  --primary: #CCFF00;
  --secondary: #1A1A1A;
  --background: #121212;
  --text: #FFFFFF;
  --text-secondary: #CCCCCC;
  --border-radius-sm: 8px;
  --border-radius-md: 12px;
  --border-radius-lg: 16px;
  --header-height: 60px;
  --bottom-nav-height: 60px;
  --safe-area-inset-bottom: env(safe-area-inset-bottom, 0);
}

/* Base Styles */
body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--background);
  color: var(--text);
  margin: 0;
  padding: 0;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  padding-bottom: calc(var(--bottom-nav-height) + var(--safe-area-inset-bottom));
}

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

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

/* Accessibility improvements */
a:focus, button:focus, input:focus, select:focus, textarea:focus {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
}

a:focus:not(:focus-visible), button:focus:not(:focus-visible), 
input:focus:not(:focus-visible), select:focus:not(:focus-visible), 
textarea:focus:not(:focus-visible) {
  outline: none;
}

a:focus-visible, button:focus-visible, input:focus-visible, 
select:focus-visible, textarea:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
}

/* Container */
.container {
  width: 100%;
  padding-left: 1rem;
  padding-right: 1rem;
  margin-left: auto;
  margin-right: auto;
  box-sizing: border-box;
}

/* Mobile Header - Fixed with Glassmorphism */
.mobile-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  background: rgba(18, 18, 18, 0.85);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.mobile-header .logo {
  height: 32px;
  width: auto;
}

.mobile-header .search-button,
.mobile-header .menu-button,
.mobile-header .back-button {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text);
  border: none;
  cursor: pointer;
  transition: background-color 0.2s ease;
}

.mobile-header .search-button:hover,
.mobile-header .menu-button:hover,
.mobile-header .back-button:hover {
  background: rgba(255, 255, 255, 0.2);
}

/* Mobile Search Overlay */
.mobile-search-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(18, 18, 18, 0.98);
  z-index: 2000;
  display: flex;
  flex-direction: column;
  padding: 1rem;
  transform: translateY(-100%);
  transition: transform 0.3s ease;
}

.mobile-search-overlay.active {
  transform: translateY(0);
}

.mobile-search-overlay .search-header {
  display: flex;
  align-items: center;
  margin-bottom: 1rem;
}

.mobile-search-overlay .search-input {
  flex: 1;
  height: 48px;
  background: rgba(255, 255, 255, 0.1);
  border: none;
  border-radius: var(--border-radius-md);
  padding: 0 1rem;
  color: var(--text);
  font-size: 16px;
}

.mobile-search-overlay .close-button {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text);
  font-size: 24px;
  background: transparent;
  border: none;
  cursor: pointer;
}

/* Mobile Sidebar Menu */
.mobile-sidebar {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: 85%;
  max-width: 320px;
  background: var(--secondary);
  z-index: 2000;
  transform: translateX(-100%);
  transition: transform 0.3s ease;
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}

.mobile-sidebar.active {
  transform: translateX(0);
}

.sidebar-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 1999;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
}

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

.mobile-sidebar-header {
  height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.mobile-sidebar-content {
  flex: 1;
  padding: 1rem;
}

.mobile-sidebar-footer {
  padding: 1rem;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.mobile-nav-item {
  display: flex;
  align-items: center;
  padding: 0.75rem 0;
  color: var(--text);
  font-weight: 500;
}

.mobile-nav-item i {
  margin-right: 1rem;
  font-size: 1.25rem;
  color: var(--primary);
}

/* Mobile Bottom Navigation */
.mobile-bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: var(--bottom-nav-height);
  background: rgba(18, 18, 18, 0.95);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: space-around;
  padding-bottom: var(--safe-area-inset-bottom);
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  border-radius: var(--border-radius-lg) var(--border-radius-lg) 0 0;
}

.nav-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  font-size: 0.75rem;
  flex: 1;
}

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

.nav-item i {
  font-size: 1.5rem;
  margin-bottom: 0.25rem;
}

/* Hero Section */
.mobile-hero {
  position: relative;
  border-radius: var(--border-radius-lg);
  overflow: hidden;
  aspect-ratio: 16/9;
}

.mobile-hero-image {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.mobile-hero-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 1.5rem 1rem;
  background: linear-gradient(to top, rgba(0, 0, 0, 0.8), transparent);
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.mobile-hero-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0 0 0.5rem;
  color: var(--text);
  text-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}

.mobile-hero-subtitle {
  font-size: 0.875rem;
  margin: 0 0 1rem;
  color: var(--text-secondary);
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
}

.mobile-hero-button {
  display: inline-flex;
  align-items: center;
  background: var(--primary);
  color: #000;
  font-weight: 600;
  padding: 0.5rem 1rem;
  border-radius: var(--border-radius-md);
  font-size: 0.875rem;
}

/* Content Sections */
.mobile-content-section {
  margin-bottom: 2rem;
}

.mobile-section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
}

.mobile-section-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 0;
}

.mobile-section-link {
  color: var(--primary);
  font-size: 0.875rem;
  display: flex;
  align-items: center;
}

/* Cards Layout */
.mobile-cards-row {
  display: flex;
  overflow-x: auto;
  gap: 1rem;
  padding: 0.25rem 0.25rem 0.5rem;
  scroll-snap-type: x mandatory;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

.mobile-cards-row::-webkit-scrollbar {
  display: none;
}

.mobile-card {
  min-width: 160px;
  width: 160px;
  border-radius: var(--border-radius-md);
  overflow: hidden;
  background: var(--secondary);
  scroll-snap-align: start;
}

.mobile-card-wide {
  min-width: 280px;
  width: 280px;
}

.mobile-card-image {
  width: 100%;
  aspect-ratio: 2/3;
  object-fit: cover;
  background-color: #2a2a2a; /* Placeholder color */
}

.mobile-card-content {
  padding: 0.75rem;
}

.mobile-card-title {
  font-size: 0.875rem;
  font-weight: 500;
  margin: 0 0 0.5rem;
  line-height: 1.3;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.mobile-card-meta {
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  color: var(--text-secondary);
}

/* Category Pills */
.mobile-category-pills {
  display: flex;
  overflow-x: auto;
  gap: 0.75rem;
  padding: 0.5rem 0 1.5rem;
  scroll-snap-type: x mandatory;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
  margin: 0 -1rem;
  padding-left: 1rem;
  padding-right: 1rem;
}

.mobile-category-pills::-webkit-scrollbar {
  display: none;
}

.mobile-category-pill {
  display: flex;
  align-items: center;
  padding: 0.5rem 1rem;
  background: var(--secondary);
  border-radius: 9999px;
  font-size: 0.875rem;
  white-space: nowrap;
  scroll-snap-align: start;
}

.mobile-category-pill.active {
  background: var(--primary);
  color: #000;
  font-weight: 500;
}

/* Grid Layouts */
.mobile-grid {
  display: grid;
  gap: 1rem;
}

.mobile-grid-3 {
  grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
  gap: 0.75rem;
}

/* Video Player */
.mobile-video-player {
  width: 100%;
  aspect-ratio: 16/9;
  background: #000;
  margin-bottom: 1rem;
  position: relative;
  overflow: hidden;
  border-radius: var(--border-radius-sm);
}

/* Skeleton Loading */
.skeleton {
  background: linear-gradient(90deg, #2a2a2a 25%, #333 50%, #2a2a2a 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s infinite;
  border-radius: var(--border-radius-sm);
}

@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* Utility Classes */
.mobile-pt-header {
  padding-top: var(--header-height);
}

.mobile-pb-nav {
  padding-bottom: var(--bottom-nav-height);
}

.mobile-rounded-lg {
  border-radius: var(--border-radius-lg);
}

.mobile-rounded-md {
  border-radius: var(--border-radius-md);
}

.mobile-rounded-sm {
  border-radius: var(--border-radius-sm);
}

/* Buttons */
.mobile-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1rem;
  border-radius: var(--border-radius-md);
  font-weight: 500;
  font-size: 0.875rem;
  transition: all 0.2s ease;
  border: none;
  cursor: pointer;
}

.mobile-btn:active {
  transform: translateY(1px);
}

.mobile-btn-primary {
  background: var(--primary);
  color: #000;
}

.mobile-btn-secondary {
  background: var(--secondary);
  color: var(--text);
}

.mobile-btn-outline {
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.2);
  color: var(--text);
}

/* Glassmorphism */
.mobile-glass {
  background: rgba(26, 26, 26, 0.8);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.05);
}

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

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

.mobile-fade-in {
  animation: fadeIn 0.3s ease;
}

.mobile-slide-up {
  animation: slideUp 0.3s ease;
}

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

/* High Contrast Mode */
@media (prefers-contrast: high) {
  :root {
    --primary: #FFFF00;
    --text: #FFFFFF;
    --text-secondary: #FFFFFF;
    --background: #000000;
    --secondary: #333333;
  }
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* Performance Optimizations */
.will-change-transform {
  will-change: transform;
}

.backface-visibility-hidden {
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
}

/* Lazy Loading */
.mobile-lazy-image {
  opacity: 0;
  transition: opacity 0.3s ease;
}

.mobile-lazy-image.loaded {
  opacity: 1;
}

/* Print Styles */
@media print {
  .mobile-header,
  .mobile-bottom-nav,
  .mobile-sidebar,
  .mobile-search-overlay {
    display: none !important;
  }
  
  body {
    background: #fff;
    color: #000;
  }
}