/* ============================================================
   StudyHub Responsive Breakpoints
   ============================================================ */

/* ── 360px+ Small Mobile ── */
@media (min-width: 360px) {
  .class-cards {
    gap: var(--space-3);
  }
  
  .subject-grid {
    gap: var(--space-3);
  }
}

/* ── 414px+ Large Mobile ── */
@media (min-width: 414px) {
  .hero-banner {
    padding: var(--space-6);
  }
  
  .hero-content h3 {
    font-size: var(--text-2xl);
  }
  
  .quiz-question {
    font-size: var(--text-xl);
  }
}

/* ── 480px+ Phablet ── */
@media (min-width: 480px) {
  .subject-grid {
    grid-template-columns: repeat(4, 1fr);
  }
  
  .auth-form-container {
    padding: var(--space-8);
  }
}

/* ── 768px+ Tablet ── */
@media (min-width: 768px) {
  :root {
    --header-height: 64px;
    --bottom-nav-height: 0px;
  }
  
  body {
    font-size: var(--text-md);
  }
  
  .container {
    padding: 0 var(--space-6);
  }
  
  /* Hide bottom nav on tablet+ */
  .bottom-nav {
    display: none;
  }
  
  /* Remove bottom padding for nav */
  .page-content {
    padding-bottom: var(--space-6);
  }
  
  /* Show desktop navigation in header */
  .desktop-nav {
    display: flex;
  }
  
  .mobile-only {
    display: none !important;
  }
  
  /* Auth pages */
  .auth-page {
    align-items: center;
    justify-content: center;
    padding: var(--space-6);
  }
  
  .auth-form-container {
    border-radius: var(--radius-2xl);
    max-width: 440px;
    width: 100%;
    box-shadow: var(--shadow-lg);
  }
  
  .auth-header {
    padding: var(--space-6);
  }
  
  /* Home page */
  .home-content {
    max-width: 800px;
    margin: 0 auto;
  }
  
  .hero-banner {
    min-height: 180px;
    padding: var(--space-8);
  }
  
  .hero-illustration {
    width: 140px;
    height: 140px;
  }
  
  .class-cards {
    max-width: 600px;
    margin: 0 auto;
    gap: var(--space-4);
  }
  
  .subject-grid {
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-4);
    max-width: 800px;
    margin: 0 auto;
  }
  
  .subject-card {
    padding: var(--space-5) var(--space-4);
  }
  
  .subject-card-icon {
    width: 56px;
    height: 56px;
  }
  
  .subject-card-name {
    font-size: var(--text-sm);
  }
  
  /* Subject list */
  .subject-list {
    max-width: 700px;
    margin: 0 auto;
  }
  
  /* Chapter list */
  .chapter-list {
    max-width: 700px;
    margin: 0 auto;
  }
  
  /* Resource list */
  .resource-list {
    max-width: 700px;
    margin: 0 auto;
  }
  
  /* Quiz */
  .quiz-question-container {
    max-width: 700px;
    margin: 0 auto;
  }
  
  /* Profile */
  .profile-content {
    max-width: 600px;
    margin: 0 auto;
  }
  
  /* Search */
  .search-results {
    max-width: 700px;
    margin: 0 auto;
  }
  
  /* Downloads */
  .downloads-list {
    max-width: 700px;
    margin: 0 auto;
  }
  
  /* Result */
  .result-stats {
    max-width: 500px;
    margin: 0 auto;
  }
  
  /* Splash */
  .splash-logo {
    width: 150px;
    height: 150px;
  }
  
  .splash-brand {
    font-size: var(--text-5xl);
  }
  
  /* Modals */
  .modal {
    max-width: 480px;
  }
  
  /* Toast */
  .toast-container {
    left: auto;
    max-width: 400px;
  }
}

/* ── 1024px+ Desktop ── */
@media (min-width: 1024px) {
  /* Show sidebar layout */
  .app-layout {
    display: flex;
  }
  
  .app-sidebar {
    width: var(--sidebar-width);
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    background: var(--bg-card);
    border-right: 1px solid var(--border-light);
    display: flex;
    flex-direction: column;
    overflow-y: auto;
    z-index: var(--z-sticky);
  }
  
  .app-sidebar .sidebar-logo {
    padding: var(--space-5) var(--space-4);
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: var(--text-xl);
    font-weight: var(--font-bold);
    color: var(--primary);
    border-bottom: 1px solid var(--border-light);
  }
  
  .app-sidebar .sidebar-nav {
    flex: 1;
    padding: var(--space-3) var(--space-2);
  }
  
  .app-sidebar .sidebar-item {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-3) var(--space-4);
    font-size: var(--text-base);
    font-weight: var(--font-medium);
    color: var(--text-secondary);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    cursor: pointer;
    text-decoration: none;
    min-height: 44px;
    margin-bottom: 2px;
  }
  
  .app-sidebar .sidebar-item:hover {
    background: var(--gray-50);
    color: var(--text-primary);
  }
  
  .app-sidebar .sidebar-item.active {
    background: var(--primary-50);
    color: var(--primary);
    font-weight: var(--font-semibold);
  }
  
  .app-sidebar .sidebar-item svg {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
  }
  
  /* Main content with sidebar */
  .app-main {
    margin-left: var(--sidebar-width);
    flex: 1;
    min-height: 100vh;
  }
  
  .app-main .app-header {
    left: var(--sidebar-width);
  }
  
  /* Hamburger hidden on desktop */
  .hamburger-btn {
    display: none;
  }
  
  /* Subject grid 5 cols */
  .subject-grid {
    grid-template-columns: repeat(5, 1fr);
  }
  
  /* Two column layout for chapter detail */
  .chapter-detail-layout {
    display: grid;
    grid-template-columns: 1fr 360px;
    gap: var(--space-6);
    max-width: 1000px;
    margin: 0 auto;
    padding: var(--space-6);
  }
}

/* ── 1280px+ Wide Desktop ── */
@media (min-width: 1280px) {
  .subject-grid {
    grid-template-columns: repeat(6, 1fr);
    gap: var(--space-5);
  }
  
  .home-content {
    max-width: 1000px;
  }
  
  .hero-banner {
    min-height: 200px;
  }
  
  .hero-content h3 {
    font-size: var(--text-3xl);
  }
}

/* ── 1440px+ Large Desktop ── */
@media (min-width: 1440px) {
  .container {
    max-width: 1400px;
    padding: 0 var(--space-8);
  }
}

/* ── Print ── */
@media print {
  .app-header,
  .bottom-nav,
  .drawer,
  .drawer-overlay,
  .app-sidebar,
  .toast-container {
    display: none !important;
  }
  
  .page-content {
    padding: 0 !important;
  }
  
  .app-main {
    margin-left: 0 !important;
  }
}

/* ── Dark mode support (future) ── */
@media (prefers-color-scheme: dark) {
  /* Placeholder for dark mode variables */
}