/* ============================================================================
   LMS COMPONENT LIBRARY
   Reusable UI components with consistent styling
   ============================================================================ */

/* ============================================================================
   BUTTON COMPONENTS
   ============================================================================ */

/* Base Button */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: var(--btn-padding-y) var(--btn-padding-x);
  border-radius: var(--btn-border-radius);
  border: var(--btn-border-width) solid transparent;
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--btn-font-weight);
  line-height: var(--leading-normal);
  text-decoration: none;
  cursor: pointer;
  transition: var(--btn-transition);
  white-space: nowrap;
  position: relative;
  overflow: hidden;
}

.btn:focus {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.btn:disabled,
.btn.disabled {
  opacity: 0.6;
  cursor: not-allowed;
  pointer-events: none;
}

/* Button Sizes */
.btn-sm {
  padding: 0.5rem 1rem;
  font-size: var(--text-sm);
  border-radius: var(--radius-sm);
}

.btn-lg {
  padding: 1rem 2rem;
  font-size: var(--text-lg);
  border-radius: var(--radius-lg);
}

.btn-block {
  display: flex;
  width: 100%;
}

/* Button Variants */
.btn-primary {
  background: var(--grad-primary);
  color: var(--color-light);
  box-shadow: var(--shadow-primary);
}

.btn-primary:hover:not(:disabled) {
  background: var(--grad-primary-reverse);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-primary:active:not(:disabled) {
  transform: translateY(0);
}

.btn-secondary {
  background: var(--color-secondary);
  color: var(--color-light);
  box-shadow: 0 4px 12px rgba(168, 85, 247, 0.3);
}

.btn-secondary:hover:not(:disabled) {
  background: var(--color-secondary-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(168, 85, 247, 0.4);
}

.btn-outline {
  background: transparent;
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.btn-outline:hover:not(:disabled) {
  background: var(--color-primary);
  color: var(--color-light);
  transform: translateY(-1px);
}

.btn-outline-secondary {
  background: transparent;
  border-color: var(--color-secondary);
  color: var(--color-secondary);
}

.btn-outline-secondary:hover:not(:disabled) {
  background: var(--color-secondary);
  color: var(--color-light);
}

.btn-ghost {
  background: transparent;
  border-color: transparent;
  color: var(--color-primary);
}

.btn-ghost:hover:not(:disabled) {
  background: rgba(99, 102, 241, 0.1);
  color: var(--color-primary-dark);
}

.btn-success {
  background: var(--color-success);
  color: var(--color-light);
  box-shadow: var(--shadow-success);
}

.btn-success:hover:not(:disabled) {
  background: var(--color-success-dark);
  transform: translateY(-2px);
}

.btn-danger {
  background: var(--color-danger);
  color: var(--color-light);
  box-shadow: var(--shadow-danger);
}

.btn-danger:hover:not(:disabled) {
  background: var(--color-danger-dark);
  transform: translateY(-2px);
}

.btn-warning {
  background: var(--color-warning);
  color: var(--color-light);
}

.btn-warning:hover:not(:disabled) {
  background: var(--color-warning-dark);
  transform: translateY(-2px);
}

.btn-info {
  background: var(--color-info);
  color: var(--color-light);
}

.btn-info:hover:not(:disabled) {
  background: var(--color-info-dark);
  transform: translateY(-2px);
}

.btn-light {
  background: var(--color-light);
  color: var(--color-dark-100);
  border-color: var(--color-dark-30);
}

.btn-light:hover:not(:disabled) {
  background: var(--color-dark-10);
  border-color: var(--color-dark-40);
}

.btn-dark {
  background: var(--color-dark-100);
  color: var(--color-light);
}

.btn-dark:hover:not(:disabled) {
  background: var(--color-dark-90);
  transform: translateY(-2px);
}

/* Icon Button */
.btn-icon {
  width: var(--btn-padding-y);
  height: var(--btn-padding-y);
  padding: 0;
  border-radius: var(--radius-full);
  justify-content: center;
}

.btn-icon .btn-icon-inner {
  font-size: 1rem;
}

/* ============================================================================
   CARD COMPONENTS
   ============================================================================ */

/* Base Card */
.card {
  background: var(--color-light);
  border-radius: var(--card-border-radius);
  border: var(--card-border-width) solid var(--color-dark-30);
  box-shadow: var(--card-shadow);
  overflow: hidden;
  transition: var(--transition-md);
}

.card:hover {
  box-shadow: var(--card-shadow-hover);
  transform: translateY(-4px);
}

.card-body {
  padding: var(--card-padding);
}

.card-header {
  padding: var(--space-4) var(--card-padding);
  border-bottom: 1px solid var(--color-dark-20);
  background: var(--color-dark-10);
}

.card-footer {
  padding: var(--space-4) var(--card-padding);
  border-top: 1px solid var(--color-dark-20);
  background: var(--color-dark-10);
}

/* Card Title */
.card-title {
  font-size: var(--text-xl);
  font-weight: var(--font-weight-bold);
  margin-bottom: var(--space-2);
  color: var(--color-dark-100);
}

/* Card Text */
.card-text {
  color: var(--color-dark-70);
  line-height: var(--leading-relaxed);
}

/* Card Variants */
.card-glass {
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.3);
}

.card-dark {
  background: var(--color-dark-90);
  border-color: var(--color-dark-70);
}

.card-dark .card-title,
.card-dark .card-text {
  color: var(--color-light);
}

.card-dark .card-text {
  color: var(--color-dark-40);
}

/* Course Card */
.course-card {
  background: var(--color-light);
  border-radius: var(--card-border-radius);
  border: 1px solid var(--color-dark-30);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: var(--transition-md);
  cursor: pointer;
}

.course-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-xl);
  border-color: var(--color-primary);
}

.course-image {
  height: 180px;
  background: var(--grad-primary);
  position: relative;
  overflow: hidden;
}

.course-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.course-content {
  padding: var(--space-6);
}

.course-title {
  font-size: var(--text-lg);
  font-weight: var(--font-weight-semibold);
  margin-bottom: var(--space-2);
  line-height: var(--leading-snug);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.course-meta {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  margin-bottom: var(--space-4);
  font-size: var(--text-sm);
  color: var(--color-dark-60);
}

.course-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-dark-20);
}

.course-price {
  font-size: var(--text-2xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-dark-100);
}

/* Stat Card */
.stat-card {
  background: var(--color-light);
  padding: var(--space-6);
  border-radius: var(--card-border-radius);
  display: flex;
  align-items: center;
  gap: var(--space-6);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-dark-30);
  transition: var(--transition-md);
}

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

.stat-icon {
  width: 3.5rem;
  height: 3.5rem;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  flex-shrink: 0;
}

.stat-icon.courses { background: #e0e7ff; color: #4338ca; }
.stat-icon.completed { background: #d1fae5; color: #065f46; }
.stat-icon.quizzes { background: #fef3c7; color: #92400e; }
.stat-icon.score { background: #fae8ff; color: #86198f; }
.stat-icon.students { background: #dbeafe; color: #1d4ed8; }
.stat-icon.instructors { background: #fce7f3; color: #be185d; }

.stat-info h3 {
  font-size: var(--text-2xl);
  margin-bottom: var(--space-1);
  color: var(--color-dark-100);
}

.stat-info p {
  color: var(--color-dark-60);
  font-size: var(--text-sm);
  font-weight: var(--font-weight-medium);
  margin: 0;
}

/* ============================================================================
   FORM COMPONENTS
   ============================================================================ */

/* Form Group */
.form-group {
  margin-bottom: var(--space-6);
}

.form-group label {
  display: block;
  font-size: var(--text-sm);
  font-weight: var(--font-weight-semibold);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-2);
  color: var(--color-dark-70);
}

/* Form Control */
.form-control {
  width: 100%;
  padding: var(--input-padding-y) var(--input-padding-x);
  border: var(--input-border-width) solid var(--color-dark-40);
  border-radius: var(--input-border-radius);
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--color-dark-100);
  background: var(--color-light);
  transition: var(--input-transition);
}

.form-control::placeholder {
  color: var(--color-dark-50);
}

.form-control:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.form-control:disabled {
  background: var(--color-dark-20);
  cursor: not-allowed;
}

/* Select */
select.form-control {
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3e%3cpath stroke='%236b7280' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='m6 8 4 4 4-4'/%3e%3c/svg%3e");
  background-position: right 0.5rem center;
  background-repeat: no-repeat;
  background-size: 1.5em 1.5em;
  padding-right: 2.5rem;
}

/* Textarea */
textarea.form-control {
  resize: vertical;
  min-height: 100px;
}

/* Checkbox & Radio */
.form-check {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  cursor: pointer;
}

.form-check input[type="checkbox"],
.form-check input[type="radio"] {
  width: 1.25rem;
  height: 1.25rem;
  margin-top: 0.125rem;
  accent-color: var(--color-primary);
}

.form-check-label {
  color: var(--color-dark-70);
  line-height: var(--leading-normal);
}

/* Form Validation States */
.form-control.is-valid {
  border-color: var(--color-success);
}

.form-control.is-invalid {
  border-color: var(--color-danger);
}

.form-text {
  font-size: var(--text-sm);
  color: var(--color-dark-50);
  margin-top: var(--space-2);
}

.form-error {
  font-size: var(--text-sm);
  color: var(--color-danger);
  margin-top: var(--space-2);
}

/* ============================================================================
   AVATAR COMPONENTS
   ============================================================================ */

/* Base Avatar */
.avatar {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--avatar-border-radius);
  font-weight: var(--font-weight-semibold);
  overflow: hidden;
  flex-shrink: 0;
}

.avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* Avatar Sizes */
.avatar-xs {
  width: var(--avatar-size-sm);
  height: var(--avatar-size-sm);
  font-size: var(--text-xs);
}

.avatar-sm {
  width: calc(var(--avatar-size-base) * 0.8);
  height: calc(var(--avatar-size-base) * 0.8);
  font-size: var(--text-sm);
}

.avatar-base {
  width: var(--avatar-size-base);
  height: var(--avatar-size-base);
  font-size: var(--text-base);
}

.avatar-lg {
  width: var(--avatar-size-lg);
  height: var(--avatar-size-lg);
  font-size: var(--text-lg);
}

.avatar-xl {
  width: var(--avatar-size-xl);
  height: var(--avatar-size-xl);
  font-size: var(--text-xl);
}

/* Avatar Variants */
.avatar-rounded {
  border-radius: var(--radius-md);
}

.avatar-circle {
  border-radius: var(--radius-circle);
}

.avatar-ring {
  border: 3px solid var(--color-light);
  box-shadow: var(--shadow-sm);
}

.avatar-online::after {
  content: '';
  position: absolute;
  bottom: 2px;
  right: 2px;
  width: 0.5rem;
  height: 0.5rem;
  background: var(--color-success);
  border-radius: var(--radius-circle);
  border: 2px solid var(--color-light);
}

/* Role Avatars */
.avatar-admin {
  background: var(--role-admin);
  color: var(--color-light);
}

.avatar-instructor {
  background: var(--role-instructor);
  color: var(--color-light);
}

.avatar-student {
  background: var(--role-student);
  color: var(--color-light);
}

/* ============================================================================
   NAVIGATION COMPONENTS
   ============================================================================ */

/* Nav Item */
.nav-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--nav-item-padding-y) var(--nav-item-padding-x);
  border-radius: var(--nav-item-border-radius);
  font-size: var(--text-base);
  font-weight: var(--font-weight-medium);
  color: var(--color-dark-70);
  text-decoration: none;
  transition: var(--transition-fast);
  cursor: pointer;
  border: none;
  background: transparent;
  width: 100%;
  text-align: left;
}

.nav-item:hover {
  background: var(--color-dark-20);
  color: var(--color-dark-100);
}

.nav-item.active {
  background: rgba(99, 102, 241, 0.1);
  color: var(--color-primary);
  font-weight: var(--font-weight-semibold);
}

.nav-item:focus {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* Nav Icon */
.nav-icon {
  width: 1.25rem;
  height: 1.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 1rem;
}

/* Nav Section Label */
.nav-section-label {
  font-size: var(--text-xs);
  font-weight: var(--font-weight-semibold);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-dark-50);
  padding: var(--space-4) var(--nav-item-padding-x);
  margin-top: var(--space-4);
}

/* Breadcrumb */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.breadcrumb-item {
  color: var(--color-dark-60);
  font-size: var(--text-sm);
}

.breadcrumb-item a {
  color: var(--color-primary);
}

.breadcrumb-item a:hover {
  color: var(--color-primary-dark);
}

.breadcrumb-separator {
  color: var(--color-dark-40);
}

/* ============================================================================
   BADGE COMPONENTS
   ============================================================================ */

/* Base Badge */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-full);
  font-size: var(--text-xs);
  font-weight: var(--font-weight-semibold);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  white-space: nowrap;
}

/* Badge Variants */
.badge-primary {
  background: rgba(99, 102, 241, 0.1);
  color: var(--color-primary);
}

.badge-secondary {
  background: rgba(168, 85, 247, 0.1);
  color: var(--color-secondary);
}

.badge-success {
  background: var(--color-success-light);
  color: var(--color-success-dark);
}

.badge-danger {
  background: var(--color-danger-light);
  color: var(--color-danger-dark);
}

.badge-warning {
  background: var(--color-warning-light);
  color: var(--color-warning-dark);
}

.badge-info {
  background: var(--color-info-light);
  color: var(--color-info-dark);
}

.badge-light {
  background: var(--color-dark-20);
  color: var(--color-dark-70);
}

.badge-dark {
  background: var(--color-dark-80);
  color: var(--color-light);
}

/* Badge Sizes */
.badge-sm {
  padding: 0.125rem 0.5rem;
  font-size: 0.7rem;
}

.badge-lg {
  padding: 0.375rem 1rem;
  font-size: var(--text-sm);
}

/* ============================================================================
   ALERT COMPONENTS
   ============================================================================ */

/* Base Alert */
.alert {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-4);
  border-radius: var(--radius-lg);
  font-weight: var(--font-weight-medium);
}

.alert-icon {
  font-size: 1.25rem;
  flex-shrink: 0;
}

/* Alert Variants */
.alert-success {
  background: var(--color-success-light);
  color: var(--color-success-dark);
  border: 1px solid rgba(16, 185, 129, 0.2);
}

.alert-danger {
  background: var(--color-danger-light);
  color: var(--color-danger-dark);
  border: 1px solid rgba(239, 68, 68, 0.2);
}

.alert-warning {
  background: var(--color-warning-light);
  color: var(--color-warning-dark);
  border: 1px solid rgba(245, 158, 11, 0.2);
}

.alert-info {
  background: var(--color-info-light);
  color: var(--color-info-dark);
  border: 1px solid rgba(14, 165, 233, 0.2);
}

/* ============================================================================
   TABLE COMPONENTS
   ============================================================================ */

/* Base Table */
.table-responsive {
  width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin-bottom: var(--space-4);
}

.table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  background: var(--color-light);
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin-bottom: 0;
}

.table th,
.table td {
  padding: var(--space-4) var(--space-6);
  text-align: left;
  border-bottom: 1px solid var(--color-dark-20);
}

.table th {
  background: var(--color-dark-10);
  font-weight: var(--font-weight-semibold);
  color: var(--color-dark-70);
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  white-space: nowrap;
}

.table tbody tr {
  transition: var(--transition-fast);
}

.table tbody tr:hover {
  background: var(--color-dark-10);
}

.table tbody tr:last-child td {
  border-bottom: none;
}

/* Table Variants */
.table-striped tbody tr:nth-child(odd) {
  background: var(--color-light);
}

.table-striped tbody tr:nth-child(even) {
  background: var(--color-dark-10);
}

.table-hover tbody tr:hover {
  background: var(--color-primary-light);
  color: var(--color-dark-100);
}

/* ============================================================================
   MODAL COMPONENTS
   ============================================================================ */

/* Modal Overlay */
.modal {
  display: none;
  position: fixed;
  inset: 0;
  z-index: var(--z-modal);
  background: rgba(15, 23, 42, 0.6);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
  animation: fadeIn 0.2s ease;
}

.modal.active {
  display: flex;
}

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

/* Modal Content */
.modal-content {
  background: var(--color-light);
  border-radius: var(--radius-2xl);
  width: 100%;
  max-width: 500px;
  box-shadow: var(--shadow-2xl);
  animation: modalSlideUp 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  overflow: hidden;
}

@keyframes modalSlideUp {
  from { opacity: 0; transform: translateY(30px) scale(0.97); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

.modal-header {
  padding: var(--space-6) var(--space-6) var(--space-4);
  border-bottom: 1px solid var(--color-dark-20);
}

.modal-body {
  padding: var(--space-4) var(--space-6);
}

.modal-footer {
  padding: var(--space-4) var(--space-6) var(--space-6);
  border-top: 1px solid var(--color-dark-20);
  display: flex;
  justify-content: flex-end;
  gap: var(--space-3);
}

/* ============================================================================
   UTILITY COMPONENTS
   ============================================================================ */

/* Empty State */
.empty-state {
  text-align: center;
  padding: var(--space-12);
  background: var(--color-light);
  border-radius: var(--radius-xl);
  border: 2px dashed var(--color-dark-30);
}

.empty-state-icon {
  font-size: 3rem;
  color: var(--color-dark-30);
  margin-bottom: var(--space-4);
}

.empty-state-title {
  font-size: var(--text-xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-dark-100);
  margin-bottom: var(--space-2);
}

.empty-state-text {
  color: var(--color-dark-60);
  max-width: 400px;
  margin: 0 auto;
}

/* Progress Bar */
.progress {
  height: 0.5rem;
  background: var(--color-dark-30);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.progress-bar {
  height: 100%;
  background: var(--grad-primary);
  border-radius: var(--radius-full);
  transition: width 0.3s ease;
}

/* Tag */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  padding: 0.25rem 0.5rem;
  background: var(--color-dark-20);
  border-radius: var(--radius-sm);
  font-size: var(--text-xs);
  font-weight: var(--font-weight-medium);
  color: var(--color-dark-70);
}

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

/* Mobile First - Hide on mobile */
.hidden-mobile { display: block; }
@media (max-width: 768px) {
  .hidden-mobile { display: none !important; }
}

/* Hide on desktop */
.hidden-desktop { display: none !important; }
@media (min-width: 769px) {
  .hidden-desktop { display: block !important; }
}

/* Show only on mobile */
.visible-mobile { display: none !important; }
@media (max-width: 768px) {
  .visible-mobile { display: block !important; }
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--color-dark-20);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb {
  background: var(--color-dark-40);
  border-radius: var(--radius-full);
  border: 2px solid var(--color-dark-20);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-dark-50);
}

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

/* ============================================================================
   MISSING UTILITY CLASSES
   ============================================================================ */

.glass {
  background: var(--color-light); /* fallback */
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.4);
  box-shadow: var(--shadow-sm);
}

.page-header {
  padding: 1.5rem;
  border-radius: var(--radius-xl);
  margin-bottom: 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.page-header h1 {
  font-size: var(--text-2xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-dark-100);
  margin: 0;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.page-header p {
  color: var(--color-dark-60);
  margin: 0.25rem 0 0 0;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.35rem 0.75rem;
  border-radius: 9999px;
  font-size: 0.75rem;
  font-weight: 600;
  white-space: nowrap;
}

.badge-primary {
  background: rgba(99, 102, 241, 0.1);
  color: var(--color-primary);
}