/* ============================================
   RESPONSIVE ENHANCEMENTS - MOBILE-FIRST
   Production-Grade SaaS Responsive Design
   
   Breakpoint Strategy:
   - Mobile: < 640px (primary constraint)
   - Tablet: 640px - 1024px (adaptive enhancement)
   - Desktop: > 1024px (full capability)
   ============================================ */

/* ============================================
   CSS CUSTOM PROPERTIES - RESPONSIVE TOKENS
   ============================================ */
:root {
  /* Touch-friendly sizing */
  --touch-target-min: 44px;
  --touch-target-comfortable: 48px;
  
  /* Responsive spacing scale */
  --space-responsive-xs: clamp(0.25rem, 1vw, 0.5rem);
  --space-responsive-sm: clamp(0.5rem, 2vw, 1rem);
  --space-responsive-md: clamp(1rem, 3vw, 1.5rem);
  --space-responsive-lg: clamp(1.5rem, 4vw, 2.5rem);
  --space-responsive-xl: clamp(2rem, 5vw, 4rem);
  
  /* Responsive typography */
  --font-size-responsive-xs: clamp(0.6875rem, 1.5vw, 0.75rem);
  --font-size-responsive-sm: clamp(0.75rem, 1.8vw, 0.875rem);
  --font-size-responsive-base: clamp(0.875rem, 2vw, 1rem);
  --font-size-responsive-lg: clamp(1rem, 2.5vw, 1.125rem);
  --font-size-responsive-xl: clamp(1.25rem, 3vw, 1.5rem);
  --font-size-responsive-2xl: clamp(1.5rem, 4vw, 2rem);
  --font-size-responsive-3xl: clamp(1.75rem, 5vw, 2.5rem);
  --font-size-responsive-hero: clamp(2rem, 6vw, 2.75rem);
}

/* ============================================
   GLOBAL RESPONSIVE UTILITIES
   ============================================ */

/* Hide on specific breakpoints */
.hide-mobile { display: block; }
.hide-tablet { display: block; }
.hide-desktop { display: none; }
.show-mobile { display: none; }
.show-tablet { display: none; }

/* Touch-friendly tap targets */
.touch-target {
  min-height: var(--touch-target-min);
  min-width: var(--touch-target-min);
}

/* Safe area padding for notched devices */
.safe-area-padding {
  padding-left: env(safe-area-inset-left, 0);
  padding-right: env(safe-area-inset-right, 0);
}

/* ============================================
   NAVIGATION - MOBILE OPTIMIZATIONS
   ============================================ */

/* Mobile Navigation Overlay */
.mobile-nav-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 999;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.mobile-nav-overlay.active {
  opacity: 1;
}

/* Mobile Menu Panel */
.mobile-menu-panel {
  position: fixed;
  top: 0;
  right: -100%;
  width: min(320px, 85vw);
  height: 100vh;
  background: var(--bg-surface);
  z-index: 1000;
  transition: right 0.3s ease;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}

.mobile-menu-panel.active {
  right: 0;
}

.mobile-menu-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border-default);
}

.mobile-menu-close {
  width: var(--touch-target-min);
  height: var(--touch-target-min);
  display: flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-size: 1.25rem;
  cursor: pointer;
}

.mobile-nav-links {
  padding: 1rem 0;
}

.mobile-nav-link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.875rem 1.25rem;
  color: var(--text-primary);
  text-decoration: none;
  font-size: 1rem;
  font-weight: 500;
  transition: background 0.2s;
  min-height: var(--touch-target-min);
}

.mobile-nav-link:hover,
.mobile-nav-link.active {
  background: rgba(74, 158, 255, 0.1);
  color: #4a9eff;
}

.mobile-nav-link i {
  width: 20px;
  text-align: center;
  color: var(--text-muted);
}

.mobile-nav-link.active i {
  color: #4a9eff;
}

/* Mobile Auth Section */
.mobile-auth-section {
  padding: 1rem 1.25rem;
  border-top: 1px solid var(--border-default);
  margin-top: auto;
}

.mobile-auth-buttons {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.mobile-auth-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.875rem 1rem;
  border-radius: 10px;
  font-weight: 600;
  font-size: 0.9375rem;
  text-decoration: none;
  min-height: var(--touch-target-min);
  transition: all 0.2s;
}

.mobile-auth-btn.primary {
  background: linear-gradient(135deg, #4a9eff 0%, #0066cc 100%);
  color: white;
}

.mobile-auth-btn.secondary {
  background: var(--bg-elevated);
  color: var(--text-primary);
  border: 1px solid var(--border-default);
}

/* ============================================
   CONTAINER RESPONSIVE ADJUSTMENTS
   ============================================ */
.container {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 1rem;
}

/* ============================================
   CARDS - TOUCH-FRIENDLY ENHANCEMENTS
   ============================================ */
.card-touch-friendly {
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
}

/* ============================================
   BUTTONS - MOBILE OPTIMIZATIONS
   ============================================ */
button,
.btn,
[role="button"] {
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
}

/* Ensure all interactive elements meet touch target size */
.btn-sm {
  min-height: var(--touch-target-min);
  padding: 0.5rem 1rem;
}

/* ============================================
   FORMS - MOBILE OPTIMIZATIONS
   ============================================ */
input,
select,
textarea {
  font-size: 16px; /* Prevents iOS zoom on focus */
  min-height: var(--touch-target-min);
}

/* ============================================
   SKELETON LOADERS - PERCEIVED PERFORMANCE
   ============================================ */
.skeleton {
  background: linear-gradient(
    90deg,
    var(--bg-elevated) 25%,
    var(--bg-surface) 50%,
    var(--bg-elevated) 75%
  );
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s infinite;
  border-radius: 4px;
}

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

.skeleton-text {
  height: 1em;
  margin-bottom: 0.5em;
}

.skeleton-text.short { width: 40%; }
.skeleton-text.medium { width: 70%; }
.skeleton-text.long { width: 100%; }

.skeleton-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
}

.skeleton-card {
  height: 200px;
  border-radius: 12px;
}

/* ============================================
   EMPTY STATES - RESPONSIVE
   ============================================ */
.empty-state-responsive {
  text-align: center;
  padding: var(--space-responsive-xl) var(--space-responsive-md);
}

.empty-state-responsive .empty-icon {
  width: clamp(60px, 15vw, 80px);
  height: clamp(60px, 15vw, 80px);
  margin: 0 auto 1.5rem;
}

.empty-state-responsive h3 {
  font-size: var(--font-size-responsive-xl);
  margin-bottom: 0.5rem;
}

.empty-state-responsive p {
  font-size: var(--font-size-responsive-base);
  max-width: 400px;
  margin: 0 auto;
}

/* ============================================
   LOADING STATES
   ============================================ */
.loading-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 9999;
}

.loading-spinner {
  width: 48px;
  height: 48px;
  border: 3px solid var(--border-default);
  border-top-color: #4a9eff;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

/* ============================================
   ERROR STATES - RESPONSIVE
   ============================================ */
.error-banner {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 1rem;
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid rgba(239, 68, 68, 0.2);
  border-radius: 10px;
  margin-bottom: 1rem;
}

.error-banner-icon {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #ef4444;
}

.error-banner-content {
  flex: 1;
  min-width: 0;
}

.error-banner-title {
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.error-banner-message {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

/* ============================================
   OFFLINE INDICATOR
   ============================================ */
.offline-indicator {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 0.75rem 1rem;
  background: #f59e0b;
  color: white;
  text-align: center;
  font-size: 0.875rem;
  font-weight: 500;
  z-index: 9999;
  transform: translateY(100%);
  transition: transform 0.3s ease;
}

.offline-indicator.show {
  transform: translateY(0);
}


/* ============================================
   TABLET BREAKPOINT (640px - 1024px)
   ============================================ */
@media (min-width: 640px) and (max-width: 1024px) {
  .hide-tablet { display: none !important; }
  .show-tablet { display: block !important; }
  
  .container {
    padding: 0 1.5rem;
  }
  
  /* Two-column layouts where appropriate */
  .tablet-grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.25rem;
  }
  
  /* Sidebar behavior - collapsible */
  .sidebar-collapsible {
    position: fixed;
    left: -280px;
    top: 64px;
    bottom: 0;
    width: 280px;
    background: var(--bg-surface);
    border-right: 1px solid var(--border-default);
    z-index: 100;
    transition: left 0.3s ease;
    overflow-y: auto;
  }
  
  .sidebar-collapsible.open {
    left: 0;
  }
  
  /* Hero sections - adjusted sizing */
  .hero-title {
    font-size: 2.25rem !important;
  }
  
  .hero-description {
    font-size: 1rem !important;
  }
  
  /* Cards grid - 2 columns */
  .books-grid,
  .paths-grid,
  .features-grid {
    grid-template-columns: repeat(2, 1fr) !important;
  }
  
  /* Value grid - 2x2 */
  .value-grid {
    grid-template-columns: repeat(2, 1fr) !important;
  }
  
  /* Stats grid - 2x2 */
  .stats-grid {
    grid-template-columns: repeat(2, 1fr) !important;
  }
  
  /* Decision cards - stack on tablet */
  .decision-cards {
    grid-template-columns: 1fr !important;
    max-width: 500px;
    margin: 0 auto;
  }
  
  /* Features 5-column to 3-column */
  .features-grid-5 {
    grid-template-columns: repeat(3, 1fr) !important;
  }
  
  /* Career tools - single column */
  .career-tools-grid {
    grid-template-columns: 1fr !important;
  }
  
  /* Wizard grid - single column */
  .wizard-grid {
    grid-template-columns: 1fr !important;
  }
  
  .preview-panel {
    position: static !important;
    order: -1;
  }
  
  /* Content layout - single column with toggle */
  .content-layout {
    grid-template-columns: 1fr !important;
  }
  
  /* Hide desktop sidebars */
  .sidebar-left,
  .sidebar-right {
    display: none !important;
  }
  
  /* Show mobile category nav */
  .mobile-category-nav {
    display: block !important;
  }
  
  /* Principles grid - 2 columns */
  .principles-grid {
    grid-template-columns: repeat(2, 1fr) !important;
  }
  
  /* Why content - single column */
  .why-content {
    grid-template-columns: 1fr !important;
  }
  
  /* Focus areas - 2 columns */
  .focus-areas-grid {
    grid-template-columns: repeat(2, 1fr) !important;
  }
  
  /* Tech grid - 2 columns */
  .tech-grid {
    grid-template-columns: repeat(2, 1fr) !important;
  }
  
  /* Mission vision - single column */
  .mission-vision-grid {
    grid-template-columns: 1fr !important;
  }
  
  /* Features grid - single column */
  .features-grid {
    grid-template-columns: 1fr !important;
  }
  
  /* Roles grid - 2 columns */
  .roles-grid {
    grid-template-columns: repeat(2, 1fr) !important;
  }
  
  /* Steps grid - 3 columns */
  .steps-grid {
    grid-template-columns: repeat(3, 1fr) !important;
  }
  
  .steps-grid-5 {
    grid-template-columns: repeat(3, 1fr) !important;
  }
  
  /* Template options - 2 columns */
  .template-options {
    grid-template-columns: repeat(2, 1fr) !important;
  }
  
  /* Industry options - 3 columns */
  .industry-options {
    grid-template-columns: repeat(3, 1fr) !important;
  }
  
  /* Roadmap layout */
  .roadmap-timeline {
    padding-left: 40px !important;
  }
  
  /* Hero visual - hide on tablet */
  .hero-visual {
    display: none !important;
  }
  
  /* Hero content - full width */
  .hero-text-content {
    max-width: 100% !important;
    text-align: center;
  }
  
  .hero-actions {
    justify-content: center;
  }
  
  .hero-trust-row {
    justify-content: center;
  }
}

/* ============================================
   MOBILE BREAKPOINT (< 640px)
   ============================================ */
@media (max-width: 639px) {
  .hide-mobile { display: none !important; }
  .show-mobile { display: block !important; }
  
  .container {
    padding: 0 1rem;
  }
  
  /* Typography scaling */
  h1, .h1 {
    font-size: var(--font-size-responsive-2xl) !important;
    line-height: 1.2 !important;
  }
  
  h2, .h2 {
    font-size: var(--font-size-responsive-xl) !important;
  }
  
  h3, .h3 {
    font-size: var(--font-size-responsive-lg) !important;
  }
  
  /* Navigation - show hamburger, hide desktop nav */
  .navbar-nav {
    display: none !important;
  }
  
  .mobile-menu-toggle {
    display: flex !important;
  }
  
  .navbar-auth {
    display: none !important;
  }
  
  /* Hero section - mobile optimized */
  .hero-title {
    font-size: 1.75rem !important;
    text-align: center;
  }
  
  .hero-description {
    font-size: 0.9375rem !important;
    text-align: center;
  }
  
  .hero-badge {
    margin: 0 auto 1rem !important;
  }
  
  .hero-text-content {
    text-align: center;
  }
  
  .hero-actions {
    flex-direction: column;
    gap: 0.75rem;
  }
  
  .hero-actions a,
  .hero-actions button {
    width: 100%;
    justify-content: center;
  }
  
  .hero-trust-row {
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
  }
  
  .hero-visual {
    display: none !important;
  }
  
  /* Announcement bar - compact */
  .announcement-content {
    flex-wrap: wrap;
    gap: 0.5rem;
    font-size: 0.75rem;
  }
  
  .announcement-text {
    flex: 1 1 100%;
    text-align: center;
    order: 2;
  }
  
  .announcement-badge {
    order: 1;
  }
  
  .announcement-link {
    order: 3;
    width: 100%;
    justify-content: center;
    padding-top: 0.5rem;
  }
  
  /* Value grid - single column */
  .value-grid {
    grid-template-columns: 1fr !important;
    gap: 1rem !important;
  }
  
  .value-card {
    padding: 1.25rem !important;
  }
  
  /* Section headers - centered */
  .section-header-row {
    flex-direction: column;
    text-align: center;
  }
  
  .section-title-block {
    flex-direction: column;
    text-align: center;
  }
  
  .view-all-link {
    margin-top: 0.5rem;
  }
  
  /* Features grid - single column */
  .features-grid-5 {
    grid-template-columns: 1fr !important;
    gap: 0.75rem !important;
  }
  
  .feature-card-compact {
    flex-direction: row;
    text-align: left;
    padding: 1rem !important;
    gap: 1rem;
  }
  
  .feature-icon-sm {
    margin-bottom: 0 !important;
    flex-shrink: 0;
  }
  
  .feature-content-sm {
    flex: 1;
    min-width: 0;
  }
  
  .feature-arrow {
    margin-top: 0 !important;
    opacity: 1 !important;
    transform: none !important;
  }
  
  /* Career tools - single column */
  .career-tools-section {
    padding: 1.25rem !important;
  }
  
  .career-tools-header {
    flex-direction: column;
    text-align: center;
    gap: 0.75rem;
  }
  
  .career-tools-grid {
    grid-template-columns: 1fr !important;
  }
  
  .career-tool-card {
    flex-direction: column;
  }
  
  /* Paths grid - single column */
  .paths-grid {
    grid-template-columns: 1fr !important;
  }
  
  .path-card {
    padding: 1rem !important;
  }
  
  /* Books grid - single column on small screens */
  .books-grid,
  .home-books-row {
    grid-template-columns: 1fr !important;
  }
  
  .book-card {
    display: grid;
    grid-template-columns: 100px 1fr;
    gap: 1rem;
  }
  
  .book-cover {
    aspect-ratio: 3/4;
  }
  
  .book-info {
    padding: 0.5rem 0 !important;
  }
  
  /* Stats grid - 2x2 */
  .stats-grid {
    grid-template-columns: repeat(2, 1fr) !important;
    gap: 1rem !important;
  }
  
  .stat-card {
    padding: 1rem !important;
  }
  
  .stat-value {
    font-size: 1.5rem !important;
  }
  
  /* CTA section */
  .cta-card {
    padding: 2rem 1.25rem !important;
  }
  
  .cta-buttons {
    flex-direction: column;
    width: 100%;
  }
  
  .cta-buttons a,
  .cta-buttons button {
    width: 100%;
    justify-content: center;
  }
  
  /* Quick actions */
  .quick-actions-card {
    flex-direction: column;
    text-align: center;
    gap: 1.5rem;
  }
  
  .quick-actions-buttons {
    flex-direction: column;
    width: 100%;
  }
  
  .quick-actions-buttons a {
    width: 100%;
    justify-content: center;
  }
  
  /* Decision cards - single column */
  .decision-cards {
    grid-template-columns: 1fr !important;
  }
  
  .decision-card {
    padding: 1.25rem !important;
  }
  
  /* Steps grid - 2 columns */
  .steps-grid {
    grid-template-columns: repeat(2, 1fr) !important;
    gap: 0.75rem !important;
  }
  
  .steps-grid-5 {
    grid-template-columns: repeat(2, 1fr) !important;
  }
  
  .step-card {
    padding: 1rem 0.75rem !important;
  }
  
  .step-card h4 {
    font-size: 0.8125rem !important;
  }
  
  .step-card p {
    font-size: 0.6875rem !important;
  }
  
  /* Features grid - single column */
  .features-grid {
    grid-template-columns: 1fr !important;
  }
  
  /* Roles grid - single column */
  .roles-grid {
    grid-template-columns: 1fr !important;
  }
  
  /* Process tabs - scrollable */
  .process-tabs {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    padding-bottom: 0.5rem;
    margin-bottom: 2rem !important;
  }
  
  .process-tab {
    white-space: nowrap;
    padding: 0.75rem 1rem !important;
    font-size: 0.8125rem !important;
  }
  
  /* Page headers - compact */
  .books-page-header,
  .library-page-header,
  .roadmap-page-header,
  .about-header-section {
    padding: 1.5rem 0 2rem !important;
  }
  
  .header-content h1 {
    font-size: 1.5rem !important;
  }
  
  .header-subtitle {
    font-size: 0.875rem !important;
  }
  
  .header-meta {
    flex-wrap: wrap;
    gap: 0.75rem !important;
    padding: 0.75rem 1rem !important;
  }
  
  .meta-divider {
    display: none !important;
  }
  
  .meta-item {
    flex: 1 1 auto;
    justify-content: center;
  }
  
  /* Header stats - compact */
  .header-stats {
    flex-direction: row !important;
    gap: 1rem !important;
    padding: 1rem !important;
  }
  
  .stat-divider {
    width: 1px !important;
    height: 30px !important;
  }
  
  .stat-number {
    font-size: 1.25rem !important;
  }
  
  /* Trust indicators - compact */
  .trust-indicators {
    flex-direction: row !important;
    flex-wrap: wrap;
    gap: 0.75rem !important;
    padding: 1rem !important;
  }
  
  .trust-divider {
    display: none !important;
  }
  
  .trust-stat {
    flex: 1 1 auto;
    min-width: 80px;
  }
  
  .trust-value {
    font-size: 1.25rem !important;
  }
  
  /* Content layout - single column */
  .content-layout {
    grid-template-columns: 1fr !important;
  }
  
  /* Hide sidebars on mobile */
  .sidebar-left,
  .sidebar-right,
  .books-sidebar,
  .library-sidebar {
    display: none !important;
  }
  
  /* Show mobile category nav */
  .mobile-category-nav {
    display: block !important;
  }
  
  /* Section headers - compact */
  .books-section-header,
  .library-section-header {
    flex-direction: column;
    gap: 1rem !important;
  }
  
  .section-title-group h2 {
    font-size: 1.25rem !important;
  }
  
  .section-controls {
    width: 100%;
    justify-content: space-between;
  }
  
  /* Container cards - reduced padding */
  .books-container-card,
  .library-container-card {
    padding: 1rem !important;
    border-radius: 12px !important;
  }
  
  /* Access banner - stack */
  .access-banner {
    flex-direction: column;
    text-align: center;
    gap: 0.75rem !important;
  }
  
  .access-btn {
    width: 100%;
    justify-content: center;
  }
  
  /* Pagination - compact */
  .pagination-wrapper {
    flex-wrap: wrap;
    gap: 0.75rem !important;
  }
  
  .pagination-btn {
    flex: 1;
    justify-content: center;
    min-width: 120px;
  }
  
  /* Wizard pages */
  .wizard-header {
    padding: 0.75rem 0 1rem !important;
  }
  
  .wizard-nav {
    flex-wrap: wrap;
    gap: 0.75rem !important;
  }
  
  .wizard-title {
    order: -1;
    width: 100%;
    text-align: center;
  }
  
  .wizard-title h1 {
    font-size: 1.125rem !important;
  }
  
  .wizard-content {
    padding: 1.5rem 0 3rem !important;
  }
  
  .wizard-grid {
    grid-template-columns: 1fr !important;
  }
  
  .preview-panel {
    display: none !important;
  }
  
  .config-section {
    padding: 1.25rem !important;
    border-radius: 12px !important;
  }
  
  .section-header {
    flex-direction: column;
    gap: 0.75rem !important;
  }
  
  .section-icon {
    width: 40px !important;
    height: 40px !important;
  }
  
  .section-header h2 {
    font-size: 1rem !important;
  }
  
  /* Role options - compact */
  .role-options {
    gap: 0.625rem !important;
  }
  
  .role-card {
    padding: 0.875rem !important;
  }
  
  .role-icon {
    width: 40px !important;
    height: 40px !important;
  }
  
  .role-info h3 {
    font-size: 0.875rem !important;
  }
  
  .role-info p {
    font-size: 0.75rem !important;
  }
  
  /* Template options - single column */
  .template-options {
    grid-template-columns: 1fr !important;
  }
  
  /* Wizard footer */
  .wizard-footer {
    flex-direction: column;
    gap: 0.75rem !important;
  }
  
  .btn-footer-primary,
  .btn-footer-secondary {
    width: 100%;
    justify-content: center;
  }
  
  /* Roadmap page */
  .roadmap-hero {
    padding: 2rem 0 3rem !important;
  }
  
  .roadmap-content {
    padding: 2rem 0 3rem !important;
  }
  
  /* About page */
  .about-section {
    padding: 2.5rem 0 !important;
  }
  
  .section-intro {
    flex-direction: column;
    text-align: center;
  }
  
  .why-content {
    grid-template-columns: 1fr !important;
  }
  
  .principles-grid {
    grid-template-columns: 1fr !important;
  }
  
  .focus-areas-grid {
    grid-template-columns: 1fr !important;
  }
  
  .tech-grid {
    grid-template-columns: 1fr !important;
  }
  
  .mission-vision-grid {
    grid-template-columns: 1fr !important;
  }
  
  .features-grid {
    grid-template-columns: 1fr !important;
  }
  
  /* Roadmap detail page */
  .roadmap-detail-page .content-layout {
    grid-template-columns: 1fr !important;
  }
  
  .roadmap-detail-page .sidebar {
    display: none !important;
  }
  
  .roadmap-section-header {
    flex-direction: column;
    gap: 1rem !important;
  }
  
  .legend {
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.75rem !important;
  }
  
  .visual-roadmap {
    padding: 1.5rem !important;
  }
  
  .timeline-phase {
    padding-left: 40px !important;
  }
  
  .phase-node {
    width: 44px !important;
    height: 44px !important;
  }
  
  .phase-label {
    font-size: 0.875rem !important;
  }
  
  .skills-branch {
    margin-left: 16px !important;
    padding-left: 1.25rem !important;
  }
  
  .skill-node {
    padding: 0.625rem 0.75rem !important;
  }
  
  .skill-name {
    font-size: 0.75rem !important;
  }
  
  /* Page actions */
  .page-actions {
    flex-direction: column;
    gap: 0.75rem !important;
  }
  
  .btn-action-primary,
  .btn-action-secondary {
    width: 100%;
    justify-content: center;
  }
}

/* ============================================
   VERY SMALL SCREENS (< 375px)
   ============================================ */
@media (max-width: 374px) {
  .container {
    padding: 0 0.75rem;
  }
  
  .hero-title {
    font-size: 1.5rem !important;
  }
  
  .hero-actions a,
  .hero-actions button {
    padding: 0.75rem 1rem !important;
    font-size: 0.875rem !important;
  }
  
  .stats-grid {
    grid-template-columns: 1fr !important;
  }
  
  .steps-grid,
  .steps-grid-5 {
    grid-template-columns: 1fr !important;
  }
  
  .header-stats {
    flex-direction: column !important;
  }
  
  .stat-divider {
    width: 60px !important;
    height: 1px !important;
  }
}

/* ============================================
   LARGE DESKTOP (> 1440px)
   ============================================ */
@media (min-width: 1440px) {
  .container {
    max-width: 1400px;
  }
  
  /* Larger spacing for big screens */
  .home-section {
    padding: 5rem 0;
  }
  
  .hero-title {
    font-size: 3rem !important;
  }
}

/* ============================================
   REDUCED MOTION PREFERENCES
   ============================================ */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  
  .skeleton {
    animation: none;
    background: var(--bg-elevated);
  }
  
  .floating-icon {
    animation: none;
  }
  
  .hero-glow {
    animation: none;
  }
}

/* ============================================
   HIGH CONTRAST MODE
   ============================================ */
@media (prefers-contrast: high) {
  .btn-hero-primary,
  .btn-cta-primary,
  .card-cta {
    border: 2px solid currentColor;
  }
  
  .feature-card-compact,
  .path-card,
  .book-card {
    border-width: 2px;
  }
}

/* ============================================
   PRINT STYLES
   ============================================ */
@media print {
  .navbar,
  .mobile-menu-toggle,
  .mobile-nav-overlay,
  .mobile-menu-panel,
  .announcement-bar,
  .cta-section,
  footer {
    display: none !important;
  }
  
  .container {
    max-width: 100%;
    padding: 0;
  }
  
  .hero-bg-effects,
  .hero-glow,
  .floating-icon {
    display: none !important;
  }
  
  body {
    background: white;
    color: black;
  }
}

/* ============================================
   NAVIGATION DROPDOWN - BOOKS MENU
   Unified entry point for Books & My Library
   ============================================ */

/* Desktop Dropdown Container */
.nav-dropdown {
  position: relative;
}

.nav-dropdown-trigger {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-size: 0.9375rem;
  font-weight: 500;
  padding: 0.5rem 0.75rem;
  cursor: pointer;
  transition: color 0.2s ease;
  font-family: inherit;
}

.nav-dropdown-trigger:hover,
.nav-dropdown-trigger.active {
  color: #4a9eff;
}

.nav-dropdown-chevron {
  font-size: 0.625rem;
  transition: transform 0.2s ease;
}

.nav-dropdown-trigger[aria-expanded="true"] .nav-dropdown-chevron {
  transform: rotate(180deg);
}

/* Dropdown Panel */
.nav-dropdown-panel {
  position: absolute;
  top: calc(100% + 0.5rem);
  left: 50%;
  transform: translateX(-50%) scale(0.95);
  min-width: 280px;
  background: var(--bg-surface);
  border: 1px solid var(--border-default);
  border-radius: 12px;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
  opacity: 0;
  visibility: hidden;
  transition: all 0.2s ease;
  z-index: 1000;
  overflow: hidden;
}

.nav-dropdown-panel.show {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) scale(1);
}

/* Dropdown Items */
.nav-dropdown-item {
  display: flex;
  align-items: flex-start;
  gap: 0.875rem;
  padding: 1rem 1.25rem;
  text-decoration: none;
  color: var(--text-primary);
  transition: background 0.15s ease;
  border-bottom: 1px solid var(--border-default);
}

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

.nav-dropdown-item:hover {
  background: rgba(74, 158, 255, 0.08);
}

.nav-dropdown-item-disabled {
  cursor: default;
  opacity: 0.7;
}

.nav-dropdown-item-disabled:hover {
  background: transparent;
}

.nav-dropdown-icon {
  width: 40px;
  height: 40px;
  background: rgba(74, 158, 255, 0.1);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.nav-dropdown-icon i {
  font-size: 1rem;
  color: #4a9eff;
}

.nav-dropdown-content {
  display: flex;
  flex-direction: column;
  gap: 0.125rem;
}

.nav-dropdown-title {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--text-primary);
}

.nav-dropdown-desc {
  font-size: 0.8125rem;
  color: var(--text-secondary);
  line-height: 1.4;
}

.nav-dropdown-login-link {
  color: #4a9eff;
  text-decoration: none;
  font-weight: 500;
}

.nav-dropdown-login-link:hover {
  text-decoration: underline;
}

/* ============================================
   MOBILE NAVIGATION - BOOKS SECTION
   ============================================ */
.mobile-nav-section {
  border-bottom: 1px solid var(--border-default);
  padding-bottom: 0.5rem;
  margin-bottom: 0.5rem;
}

.mobile-nav-section-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1.25rem;
  color: var(--text-muted);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.mobile-nav-section-header i {
  width: 20px;
  text-align: center;
  font-size: 0.875rem;
}

.mobile-nav-section-items {
  padding-left: 0.5rem;
}

.mobile-nav-sublink {
  padding-left: 2.5rem !important;
}

.mobile-nav-sublink i {
  font-size: 0.875rem;
}

.mobile-nav-disabled {
  opacity: 0.5;
  cursor: default;
  pointer-events: none;
}

.mobile-nav-disabled small {
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* ============================================
   RESPONSIVE ADJUSTMENTS FOR DROPDOWN
   ============================================ */
@media (max-width: 1024px) {
  .nav-dropdown-panel {
    min-width: 260px;
  }
}

@media (max-width: 768px) {
  /* Hide desktop dropdown on mobile */
  .nav-dropdown {
    display: none;
  }
}

@media (min-width: 769px) {
  /* Hide mobile books section on desktop */
  .mobile-nav-section {
    display: none;
  }
}