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

:root {
  --primary-color: #1a4b8c;
  --primary-dark: #0d2d5a;
  --secondary-color: #4a6fa5;
  --accent-color: #d4a84b;
  --accent-light: #f5d78e;
  --background-color: #f8fafc;
  --card-background: #ffffff;
  --text-color: #1a365d;
  --text-light: #4a6fa5;
  --border-color: #d1e3f6;
  --error-color: #c53030;
  --success-color: #2f855a;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  background-color: var(--background-color);
  color: var(--text-color);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Navigation */
.navbar {
  background-color: var(--primary-color);
  padding: 0.75rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
  position: relative;
}

.nav-brand a {
  color: white;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.nav-logo {
  height: 50px;
  width: auto;
  border-radius: 4px;
  background: white;
  padding: 2px;
}

.nav-title {
  font-size: 1.3rem;
  font-weight: bold;
  color: white;
}

/* Hamburger Menu Button */
.hamburger {
  display: flex;
  flex-direction: column;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  z-index: 1001;
}

.hamburger span {
  width: 25px;
  height: 3px;
  background-color: white;
  margin: 3px 0;
  transition: 0.3s;
  border-radius: 3px;
}

.hamburger.active span:nth-child(1) {
  transform: rotate(-45deg) translate(-5px, 6px);
}

.hamburger.active span:nth-child(2) {
  opacity: 0;
}

.hamburger.active span:nth-child(3) {
  transform: rotate(45deg) translate(-5px, -6px);
}

/* Navigation Links - Hidden by default, slide out from left */
.nav-links {
  position: fixed;
  left: -100%;
  top: 0;
  flex-direction: column;
  background-color: var(--primary-color);
  width: 250px;
  height: 100vh;
  padding-top: 80px;
  list-style: none;
  gap: 0;
  transition: left 0.3s ease;
  box-shadow: 2px 0 10px rgba(0,0,0,0.3);
  z-index: 1000;
}

.nav-links.active {
  left: 0;
}

.nav-links li {
  width: 100%;
}

.nav-links a {
  color: white;
  text-decoration: none;
  display: block;
  padding: 1rem 1.5rem;
  border-bottom: 1px solid rgba(255,255,255,0.1);
  transition: background-color 0.2s;
}

.nav-links a:hover {
  background-color: var(--primary-dark);
}

/* Overlay when menu is open */
.nav-links.active::before {
  content: '';
  position: fixed;
  top: 0;
  left: 250px;
  right: 0;
  bottom: 0;
  background-color: rgba(0,0,0,0.3);
  z-index: -1;
}

/* Main Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem;
  flex: 1;
}

/* Page Headers */
.page-header {
  margin-bottom: 2rem;
}

.page-header h1 {
  color: var(--primary-dark);
  margin-bottom: 0.5rem;
}

.page-header p {
  color: var(--text-light);
}

/* Cards */
.card {
  background: var(--card-background);
  border-radius: 8px;
  padding: 1.5rem;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
  margin-bottom: 1rem;
  border: 1px solid var(--border-color);
}

.card h2, .card h3 {
  color: var(--primary-dark);
  margin-bottom: 0.5rem;
}

.card p {
  color: var(--text-light);
}

/* Grid Layouts */
.grid {
  display: grid;
  gap: 1.5rem;
}

.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  text-decoration: none;
  font-size: 1rem;
  transition: background-color 0.2s, transform 0.1s;
}

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

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

.btn-primary:hover {
  background-color: var(--primary-dark);
}

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

.btn-success {
  background-color: var(--accent-color);
  color: white;
}

.btn-success:hover {
  background-color: #c09940;
}

.btn-danger {
  background-color: var(--error-color);
  color: white;
}

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

.btn-accent:hover {
  background-color: #c09940;
}

.btn-small {
  padding: 0.4rem 0.8rem;
  font-size: 0.875rem;
}

/* Forms */
.form-group {
  margin-bottom: 1.25rem;
}

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
  color: var(--text-color);
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 4px;
  font-size: 1rem;
  transition: border-color 0.2s;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary-color);
}

.form-group textarea {
  min-height: 100px;
  resize: vertical;
}

.form-group small {
  display: block;
  margin-top: 0.25rem;
  color: var(--text-light);
}

/* Checkbox group */
.checkbox-group {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.checkbox-group label {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: normal;
  cursor: pointer;
}

.checkbox-group input[type="checkbox"] {
  width: auto;
}

/* Alerts */
.alert {
  padding: 1rem 1.5rem;
  border-radius: 4px;
  margin-bottom: 1.5rem;
}

.alert-error {
  background-color: #fed7d7;
  color: var(--error-color);
  border: 1px solid var(--error-color);
}

.alert-success {
  background-color: #c6f6d5;
  color: var(--success-color);
  border: 1px solid var(--success-color);
}

/* Tables */
.table-wrapper {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  background: var(--card-background);
  border-radius: 8px;
  overflow: hidden;
}

th, td {
  padding: 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

th {
  background-color: var(--primary-color);
  color: white;
  font-weight: 500;
}

tr:hover {
  background-color: var(--background-color);
}

.actions {
  display: flex;
  gap: 0.5rem;
}

/* Stats Cards */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
  margin-bottom: 2rem;
}

.stat-card {
  background: var(--card-background);
  padding: 1.5rem;
  border-radius: 8px;
  text-align: center;
  border: 1px solid var(--border-color);
}

.stat-card .number {
  font-size: 2.5rem;
  font-weight: bold;
  color: var(--primary-color);
}

.stat-card .label {
  color: var(--text-light);
  margin-top: 0.5rem;
}

/* Material List */
.material-item {
  display: flex;
  align-items: center;
  padding: 1rem;
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  margin-bottom: 0.5rem;
  gap: 0.5rem;
}

.material-item:hover {
  border-color: var(--primary-color);
}

.material-info {
  flex: 1;
  min-width: 0;
}

.material-info h4 {
  margin-bottom: 0.25rem;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.25rem;
}

/* Class Announcement */
.class-announcement {
  background: #fff3cd;
  border: 2px solid #ffc107;
  border-radius: 8px;
  padding: 1rem 1.25rem;
  margin-bottom: 1.5rem;
  color: #856404;
  font-weight: 500;
  font-size: 1.05rem;
}

/* Student Submissions */
.submission-section {
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.25rem;
  margin-bottom: 1.5rem;
}

.submission-section h3 {
  margin-bottom: 1rem;
  color: var(--primary-dark);
}

.my-submissions-list {
  margin-bottom: 1rem;
}

.submission-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem;
  background: #f8f9fa;
  border: 1px solid var(--border-color);
  border-radius: 4px;
  margin-bottom: 0.5rem;
}

.submission-info {
  flex: 1;
}

.submission-info h4 {
  font-size: 0.95rem;
  margin-bottom: 0.25rem;
}

.submission-info p {
  font-size: 0.85rem;
  color: var(--text-light);
  margin-bottom: 0.25rem;
}

.submission-info small {
  font-size: 0.75rem;
  color: var(--text-light);
}

.submission-actions {
  display: flex;
  gap: 0.5rem;
}

.submission-form-toggle {
  margin-top: 1rem;
  cursor: pointer;
}

.submission-form-toggle summary {
  font-weight: 500;
  color: var(--primary-color);
  padding: 0.5rem;
  border-radius: 4px;
  user-select: none;
}

.submission-form-toggle summary:hover {
  background: #f0f7ff;
}

.submission-form-toggle[open] summary {
  margin-bottom: 1rem;
}

.submission-form {
  padding: 1rem;
  background: #f8f9fa;
  border-radius: 4px;
}

/* Alert Messages */
.alert {
  padding: 1rem;
  border-radius: 4px;
  margin-bottom: 1rem;
}

.alert-success {
  background: #d4edda;
  color: #155724;
  border: 1px solid #c3e6cb;
}

.alert-error {
  background: #f8d7da;
  color: #721c24;
  border: 1px solid #f5c6cb;
}

.material-info p {
  font-size: 0.875rem;
  color: var(--text-light);
}

.material-actions {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

/* Highlighted sections */
.highlighted-section {
  background: var(--card-background);
  border-radius: 8px;
  padding: 1.25rem;
  margin-bottom: 1.5rem;
  border: 2px solid var(--border-color);
}

.highlighted-section h3 {
  margin-bottom: 1rem;
  color: var(--primary-dark);
}

.highlighted-section.today-section {
  border-color: #e53e3e;
  background: #fff5f5;
}

.highlighted-section.today-section h3 {
  color: #c53030;
}

.highlighted-section.week-section {
  border-color: var(--accent-color);
  background: #fffdf5;
}

.highlighted-section.week-section h3 {
  color: #b7791f;
}

.highlighted-section.favorites-section {
  border-color: #d69e2e;
  background: #fffff0;
}

.highlighted-section.favorites-section h3 {
  color: #b7791f;
}

/* Material Cards Grid */
.material-cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 1rem;
}

.material-card {
  position: relative;
  background: var(--card-background);
  border: 2px solid var(--border-color);
  border-radius: 8px;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  transition: all 0.2s;
}

.material-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.material-card.card-today {
  border-color: #fc8181;
  background: white;
}

.material-card.card-today:hover {
  border-color: #e53e3e;
  background: #fff5f5;
}

.material-card.card-week {
  border-color: var(--accent-light);
  background: white;
}

.material-card.card-week:hover {
  border-color: var(--accent-color);
  background: #fffdf5;
}

.material-card-content {
  flex: 1;
  display: flex;
  flex-direction: column;
}

.material-card-content h4 {
  font-size: 0.95rem;
  margin-bottom: 0.5rem;
  color: var(--primary-dark);
  line-height: 1.3;
}

.material-card-desc {
  font-size: 0.8rem;
  color: var(--text-light);
  margin-bottom: 0.75rem;
  flex: 1;
  line-height: 1.4;
}

.material-card-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: auto;
}

.star-form-compact {
  position: absolute;
  top: 0.5rem;
  right: 0.5rem;
}

.star-btn-compact {
  background: none;
  border: none;
  font-size: 1.2rem;
  cursor: pointer;
  color: #cbd5e0;
  padding: 0;
  transition: color 0.2s, transform 0.1s;
  line-height: 1;
}

.star-btn-compact:hover {
  color: #d69e2e;
  transform: scale(1.15);
}

.star-btn-compact.starred {
  color: #d69e2e;
}

/* Star button */
.star-form {
  display: flex;
  align-items: center;
}

.star-btn {
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: #cbd5e0;
  padding: 0;
  margin-right: 0.75rem;
  transition: color 0.2s, transform 0.1s;
  line-height: 1;
}

.star-btn:hover {
  color: #d69e2e;
  transform: scale(1.1);
}

.star-btn.starred {
  color: #d69e2e;
}

/* Status badges */
.status-badge {
  display: inline-block;
  padding: 0.15rem 0.5rem;
  border-radius: 3px;
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  margin-left: 0.5rem;
  vertical-align: middle;
}

.status-badge.today {
  background: #fed7d7;
  color: #c53030;
}

.status-badge.week {
  background: #fefcbf;
  color: #b7791f;
}

/* Material item with highlight */
.material-item.highlight-today {
  border-left: 3px solid #e53e3e;
}

.material-item.highlight-week {
  border-left: 3px solid var(--accent-color);
}

.material-type {
  display: inline-block;
  padding: 0.2rem 0.5rem;
  background: var(--primary-color);
  color: white;
  border-radius: 3px;
  font-size: 0.75rem;
  text-transform: uppercase;
  margin-left: 0.5rem;
}

/* Unit sections */
.unit-section {
  margin-bottom: 2rem;
}

.unit-section h3 {
  color: var(--primary-dark);
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--primary-color);
  margin-bottom: 1rem;
}

/* Unit filter */
.unit-filter {
  background: var(--card-background);
  padding: 1rem 1.5rem;
  border-radius: 8px;
  margin-bottom: 1.5rem;
  border: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  gap: 1rem;
}

.unit-filter label {
  font-weight: 500;
  color: var(--text-color);
}

.unit-filter select {
  padding: 0.5rem 1rem;
  border: 1px solid var(--border-color);
  border-radius: 4px;
  font-size: 1rem;
  background: white;
  cursor: pointer;
  min-width: 200px;
}

.unit-filter select:focus {
  outline: none;
  border-color: var(--primary-color);
}

/* Login Page */
.login-container {
  max-width: 400px;
  margin: 2rem auto;
}

/* Hero Section */
.hero {
  text-align: center;
  padding: 3rem 2rem;
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
  color: white;
  border-radius: 8px;
  margin-bottom: 2rem;
  border-bottom: 4px solid var(--accent-color);
}

.hero h1 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.hero p {
  font-size: 1.2rem;
  opacity: 0.9;
}

.hero .accent {
  color: var(--accent-light);
}

/* Slider */
.slider-container {
  position: relative;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto 2rem;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.slider {
  position: relative;
  width: 100%;
  height: 400px;
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
}

.slide {
  position: absolute;
  width: 100%;
  height: 100%;
  opacity: 0;
  transition: opacity 0.5s ease-in-out;
  display: flex;
  align-items: center;
  justify-content: center;
  pointer-events: none; /* Prevent inactive slides from blocking clicks */
}

.slide.active {
  opacity: 1;
  pointer-events: auto; /* Allow clicks on active slide */
  z-index: 1; /* Ensure active slide is on top */
}

.slide-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 1100px;
  width: 100%;
  padding: 2rem;
  gap: 2rem;
}

.slide-text {
  flex: 1;
  color: white;
  text-align: left;
}

.slide-text h2 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
  color: var(--accent-light);
}

.slide-text h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  font-weight: 600;
}

.slide-text p {
  font-size: 1.1rem;
  margin-bottom: 1.5rem;
  line-height: 1.6;
  opacity: 0.95;
}

.slide-image {
  flex: 0 0 300px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.slide-image img {
  max-width: 100%;
  max-height: 350px;
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.3);
  background: white;
  padding: 10px;
}

/* Slider Navigation Buttons */
.slider-btn {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  background: rgba(255,255,255,0.3);
  color: white;
  border: none;
  font-size: 2rem;
  padding: 0.5rem 1rem;
  cursor: pointer;
  border-radius: 4px;
  transition: background 0.3s;
  z-index: 10;
  display: none; /* Hidden - slider advances automatically */
}

.slider-btn:hover {
  background: rgba(255,255,255,0.5);
}

.slider-btn.prev {
  left: 1rem;
}

.slider-btn.next {
  right: 1rem;
}

/* Slider Dots */
.slider-dots {
  position: absolute;
  bottom: 1rem;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 0.75rem;
  z-index: 10;
}

.dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: rgba(255,255,255,0.5);
  cursor: pointer;
  transition: background 0.3s, transform 0.2s;
}

.dot:hover {
  background: rgba(255,255,255,0.8);
  transform: scale(1.2);
}

.dot.active {
  background: var(--accent-color);
  transform: scale(1.3);
}

/* Footer */
.footer {
  background-color: var(--primary-dark);
  color: white;
  text-align: center;
  padding: 1.5rem;
  margin-top: auto;
}

/* Admin Sidebar Layout */
.admin-layout {
  display: flex;
  gap: 2rem;
  min-height: calc(100vh - 200px);
}

.admin-sidebar {
  width: 200px;
  flex-shrink: 0;
  background: var(--card-background);
  padding: 1rem;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  height: fit-content;
  position: sticky;
  top: 1rem;
}

.admin-sidebar a {
  display: block;
  padding: 0.75rem 1rem;
  color: var(--text-color);
  text-decoration: none;
  border-radius: 4px;
  margin-bottom: 0.25rem;
}

.admin-sidebar a:hover,
.admin-sidebar a.active {
  background-color: var(--primary-color);
  color: white;
}

.admin-content {
  flex: 1;
}

/* Admin filters */
.admin-filter {
  margin-bottom: 1rem;
}

.admin-filter input {
  width: 100%;
  max-width: 400px;
  padding: 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 4px;
  font-size: 1rem;
}

.admin-filter input:focus {
  outline: none;
  border-color: var(--primary-color);
}

.admin-filter-group {
  display: flex;
  gap: 1rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.admin-filter-group input,
.admin-filter-group select {
  padding: 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 4px;
  font-size: 1rem;
}

.admin-filter-group input {
  flex: 1;
  min-width: 200px;
}

.admin-filter-group select {
  min-width: 150px;
}

.admin-filter-group input:focus,
.admin-filter-group select:focus {
  outline: none;
  border-color: var(--primary-color);
}

/* Quick Action Buttons */
.quick-actions {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1rem;
  margin-bottom: 1rem;
}

.quick-action-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 1.5rem 1rem;
  background: var(--card-background);
  border: 2px solid var(--border-color);
  border-radius: 8px;
  text-decoration: none;
  color: var(--text-color);
  transition: all 0.2s;
}

.quick-action-btn:hover {
  border-color: var(--primary-color);
  background: var(--primary-color);
  color: white;
  transform: translateY(-2px);
}

.quick-action-icon {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
}

.quick-action-label {
  font-weight: 500;
  text-align: center;
}

/* Class quick links */
.class-quick-links {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.class-quick-link {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 1.25rem;
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  text-decoration: none;
  color: var(--text-color);
  transition: all 0.2s;
}

.class-quick-link:hover {
  border-color: var(--primary-color);
  background: #f0f7ff;
}

.class-quick-link .material-count {
  font-size: 0.875rem;
  color: var(--text-light);
}

/* Responsive */
@media (max-width: 768px) {
  .navbar {
    flex-direction: column;
    gap: 1rem;
    padding: 1rem;
  }
  
  .nav-brand a {
    flex-direction: column;
    text-align: center;
  }
  
  .nav-logo {
    height: 60px;
  }
  
  .nav-title {
    font-size: 1.1rem;
  }
  
  .nav-links {
    flex-wrap: wrap;
    justify-content: center;
  }
  
  .admin-layout {
    flex-direction: column;
  }
  
  .admin-sidebar {
    width: 100%;
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    position: static;
    padding: 0.75rem;
  }
  
  .admin-sidebar a {
    margin-bottom: 0;
    padding: 0.5rem 0.75rem;
  }
  
  .hero h1 {
    font-size: 1.8rem;
  }
  
  .hero img {
    height: 80px !important;
  }
  
  .quick-actions {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .quick-action-btn {
    padding: 1rem 0.5rem;
  }
  
  .material-cards-grid {
    grid-template-columns: 1fr;
  }
  
  /* Slider responsive */
  .slider {
    height: auto;
    min-height: 520px; /* Even more height */
  }
  
  .slide {
    display: none; /* Hide all slides by default on mobile */
    position: relative;
    height: auto;
    min-height: 500px;
  }
  
  .slide.active {
    display: flex; /* Only show active slide */
  }
  
  .slide-content {
    flex-direction: column;
    text-align: center;
    padding: 2rem 1rem;
    min-height: 480px;
    justify-content: center;
  }
  
  .slide-text {
    text-align: center;
    margin-bottom: 1rem;
  }
  
  .slide-text h2 {
    font-size: 1.4rem;
    margin-bottom: 0.5rem;
  }
  
  .slide-text h3 {
    font-size: 1.1rem;
    margin-bottom: 0.75rem;
    line-height: 1.4;
  }
  
  .slide-text p {
    font-size: 0.9rem;
    margin-bottom: 1rem;
    line-height: 1.5;
  }
  
  .slide-image {
    flex: 0 0 auto;
    margin-top: 0.5rem;
  }
  
  .slide-image img {
    max-width: 200px;
    max-height: 200px;
  }
  
  .slider-btn {
    font-size: 1.5rem;
    padding: 0.25rem 0.75rem;
  }
  
  /* Ensure buttons in slides are visible and clickable on mobile */
  .slide-text .btn {
    display: inline-block;
    margin-top: 0.5rem;
    font-size: 0.9rem;
    padding: 0.5rem 1rem;
  }
  
  /* Slider dots - make them more visible on mobile */
  .slider-dots {
    bottom: 1rem;
  }
}

/* ============ PROGRESS TRACKING ============ */

/* Completion button in material list */
.complete-form {
  flex-shrink: 0;
}

.complete-btn {
  background: none;
  border: 2px solid #cbd5e0;
  color: #cbd5e0;
  font-size: 1.2rem;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  cursor: pointer;
  transition: all 0.2s;
  padding: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}

.complete-btn:hover {
  border-color: var(--primary-color);
  color: var(--primary-color);
  transform: scale(1.1);
}

.complete-btn.completed {
  background: #38a169;
  border-color: #38a169;
  color: white;
}

.complete-btn.completed:hover {
  background: #2f855a;
  border-color: #2f855a;
}

/* Completion button in material cards */
.complete-form-compact {
  flex-shrink: 0;
}

.complete-btn-compact {
  background: none;
  border: 2px solid #cbd5e0;
  color: #cbd5e0;
  font-size: 1rem;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  cursor: pointer;
  transition: all 0.2s;
  padding: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}

.complete-btn-compact:hover {
  border-color: var(--primary-color);
  color: var(--primary-color);
  transform: scale(1.1);
}

.complete-btn-compact.completed {
  background: #38a169;
  border-color: #38a169;
  color: white;
}

.complete-btn-compact.completed:hover {
  background: #2f855a;
  border-color: #2f855a;
}

/* Completed material styling */
.material-item.completed {
  opacity: 0.7;
  background: #f0fff4;
}

.material-card.completed {
  opacity: 0.8;
  background: #f0fff4;
}

/* Card icons container */
.card-icons {
  position: absolute;
  top: 0.5rem;
  right: 0.5rem;
  display: flex;
  gap: 0.25rem;
}


/* Assignments Section */
.assignments-section {
  margin: 2rem 0;
  padding: 1.5rem;
  background: var(--card-background);
  border-radius: 8px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.assignments-section > h3 {
  color: var(--primary-dark);
  margin-bottom: 1.5rem;
  font-size: 1.4rem;
}

.assignment-category {
  margin-bottom: 1.5rem;
}

.assignment-category h4 {
  color: var(--primary-color);
  margin-bottom: 1rem;
  font-size: 1.2rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.assignment-card {
  background: #ffffff;
  border-left: 4px solid var(--primary-color);
  padding: 1rem;
  margin-bottom: 0.75rem;
  border-radius: 4px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
  transition: all 0.2s;
}

.assignment-card:hover {
  box-shadow: 0 2px 6px rgba(0,0,0,0.1);
  transform: translateY(-2px);
}

.assignment-card.overdue-card {
  border-left-color: #c53030;
  background: #fff5f5;
}

.assignment-card.upcoming-card {
  border-left-color: #4a6fa5;
}

.assignment-card.completed-card {
  border-left-color: #38a169;
  background: #f0fff4;
}

.assignment-header {
  display: flex;
  justify-content: space-between;
  align-items: start;
  margin-bottom: 0.5rem;
}

.assignment-header h5 {
  color: var(--primary-dark);
  font-size: 1.1rem;
  margin: 0;
  flex: 1;
}

.due-date {
  background: var(--accent-light);
  color: var(--text-color);
  padding: 0.25rem 0.75rem;
  border-radius: 12px;
  font-size: 0.85rem;
  font-weight: 600;
  white-space: nowrap;
}

.due-date.overdue {
  background: #feb2b2;
  color: #742a2a;
}

.assignment-description {
  color: var(--text-light);
  margin: 0.5rem 0;
  font-size: 0.95rem;
}

.linked-material {
  color: var(--primary-color);
  font-size: 0.9rem;
  margin: 0.5rem 0;
}

.assignment-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 0.75rem;
  padding-top: 0.75rem;
  border-top: 1px solid #e2e8f0;
}

.assignment-footer .points {
  color: var(--text-light);
  font-weight: 600;
}

.grade-badge {
  background: #38a169;
  color: white;
  padding: 0.25rem 0.75rem;
  border-radius: 12px;
  font-size: 0.85rem;
  font-weight: 600;
}

.status-badge {
  background: var(--secondary-color);
  color: white;
  padding: 0.25rem 0.75rem;
  border-radius: 12px;
  font-size: 0.85rem;
  font-weight: 600;
}

.feedback-box {
  background: #edf2f7;
  padding: 0.75rem;
  border-radius: 4px;
  margin: 0.5rem 0;
  font-size: 0.9rem;
}

.feedback-box strong {
  color: var(--primary-color);
}

/* Completed assignments collapsible */
.completed-category summary {
  cursor: pointer;
  list-style: none;
  user-select: none;
}

.completed-category summary::-webkit-details-marker {
  display: none;
}

.completed-category summary h4 {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.completed-category summary h4::before {
  content: '▶';
  display: inline-block;
  transition: transform 0.2s;
}

.completed-category[open] summary h4::before {
  transform: rotate(90deg);
}

/* Overdue category styling */
.overdue-category h4 {
  color: #c53030;
}

/* Responsive */
@media (max-width: 768px) {
  .assignment-header {
    flex-direction: column;
    gap: 0.5rem;
  }
  
  .assignment-footer {
    flex-direction: column;
    gap: 0.5rem;
    align-items: stretch;
  }
  
  .assignment-footer .btn {
    width: 100%;
    text-align: center;
  }
}