/* NextLevel LMS - Modern Stylesheet */

:root {
  --primary: #6366f1;
  --primary-dark: #4f46e5;
  --primary-light: #818cf8;
  --secondary: #0ea5e9;
  --success: #22c55e;
  --warning: #f59e0b;
  --danger: #ef4444;
  --dark: #0f172a;
  --dark-light: #1e293b;
  --gray: #64748b;
  --gray-light: #94a3b8;
  --light: #f1f5f9;
  --white: #ffffff;
  --border: #e2e8f0;
  --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
  --radius: 12px;
  --radius-sm: 8px;
}

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

body {
  font-family: "Inter", -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--light);
  color: var(--dark);
  line-height: 1.6;
}

/* Typography */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 700;
  line-height: 1.3;
  color: var(--dark);
}

h1 {
  font-size: 2.5rem;
}
h2 {
  font-size: 2rem;
}
h3 {
  font-size: 1.5rem;
}
h4 {
  font-size: 1.25rem;
}

/* Container */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  border: none;
  cursor: pointer;
  transition: all 0.2s ease;
  text-decoration: none;
}

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

.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow);
}

.btn-secondary {
  background: var(--white);
  color: var(--dark);
  border: 1px solid var(--border);
}

.btn-secondary:hover {
  background: var(--light);
  border-color: var(--gray-light);
}

.btn-success {
  background: var(--success);
  color: var(--white);
}
.btn-danger {
  background: var(--danger);
  color: var(--white);
}
.btn-lg {
  padding: 1rem 2rem;
  font-size: 1.1rem;
}
.btn-sm {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

/* Cards */
.card {
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: all 0.3s ease;
}

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

.card-body {
  padding: 1.5rem;
}

/* Course Card */
.course-card {
  display: flex;
  flex-direction: column;
  height: 100%;
}

.course-card .thumbnail {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
}

.course-card .thumbnail img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s ease;
}

.course-card:hover .thumbnail img {
  transform: scale(1.05);
}

.course-card .badge {
  position: absolute;
  top: 1rem;
  left: 1rem;
  padding: 0.25rem 0.75rem;
  background: var(--primary);
  color: var(--white);
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: 20px;
}

.course-card .badge.free {
  background: var(--success);
}

.course-card .content {
  padding: 1.25rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.course-card .category {
  font-size: 0.75rem;
  color: var(--primary);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 0.5rem;
}

.course-card .title {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.course-card .instructor {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1rem;
  color: var(--gray);
  font-size: 0.875rem;
}

.course-card .instructor img {
  width: 24px;
  height: 24px;
  border-radius: 50%;
}

.course-card .meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-top: auto;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  font-size: 0.875rem;
  color: var(--gray);
}

.course-card .rating {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  color: var(--warning);
}

.course-card .price {
  margin-left: auto;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--primary);
}

.course-card .price.free {
  color: var(--success);
}

/* Navigation */
.navbar {
  background: var(--white);
  box-shadow: var(--shadow);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
}

.navbar .logo {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--dark);
  text-decoration: none;
}

.navbar .logo span {
  color: var(--primary);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  color: var(--gray);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s;
}

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

.nav-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* Hero Section */
.hero {
  background: linear-gradient(135deg, var(--dark) 0%, var(--dark-light) 100%);
  color: var(--white);
  padding: 5rem 0;
}

.hero h1 {
  color: var(--white);
  font-size: 3.5rem;
  margin-bottom: 1.5rem;
}

.hero h1 span {
  color: var(--primary-light);
}

.hero p {
  font-size: 1.25rem;
  color: var(--gray-light);
  max-width: 600px;
  margin-bottom: 2rem;
}

/* Search Box */
.search-box {
  display: flex;
  background: var(--white);
  border-radius: var(--radius);
  overflow: hidden;
  max-width: 600px;
  box-shadow: var(--shadow-lg);
}

.search-box input {
  flex: 1;
  padding: 1rem 1.5rem;
  border: none;
  font-size: 1rem;
  outline: none;
}

.search-box button {
  padding: 1rem 2rem;
  background: var(--primary);
  color: var(--white);
  border: none;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s;
}

.search-box button:hover {
  background: var(--primary-dark);
}

/* Stats */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2rem;
  margin-top: 3rem;
}

.stat-item {
  text-align: center;
}

.stat-item .number {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--primary-light);
}

.stat-item .label {
  color: var(--gray-light);
  font-size: 0.95rem;
}

/* Section */
.section {
  padding: 5rem 0;
}

.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 2rem;
}

.section-title {
  font-size: 1.75rem;
}

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

.grid-2 {
  grid-template-columns: repeat(2, 1fr);
}
.grid-3 {
  grid-template-columns: repeat(3, 1fr);
}
.grid-4 {
  grid-template-columns: repeat(4, 1fr);
}

@media (max-width: 1024px) {
  .grid-4 {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 768px) {
  .grid-3,
  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
  .stats {
    grid-template-columns: repeat(2, 1fr);
  }
  .hero h1 {
    font-size: 2.5rem;
  }
}

@media (max-width: 480px) {
  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }
}

/* Dashboard Sidebar */
.dashboard {
  display: flex;
  min-height: 100vh;
}

.sidebar {
  width: 280px;
  background: var(--dark);
  color: var(--white);
  padding: 1.5rem;
  position: fixed;
  height: 100vh;
  overflow-y: auto;
}

.sidebar .logo {
  font-size: 1.5rem;
  font-weight: 800;
  margin-bottom: 2rem;
}

.sidebar .logo span {
  color: var(--primary-light);
}

.sidebar-nav {
  list-style: none;
}

.sidebar-nav li {
  margin-bottom: 0.5rem;
}

.sidebar-nav a {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.875rem 1rem;
  color: var(--gray-light);
  text-decoration: none;
  border-radius: var(--radius-sm);
  transition: all 0.2s;
}

.sidebar-nav a:hover,
.sidebar-nav a.active {
  background: var(--dark-light);
  color: var(--white);
}

.sidebar-nav a.active {
  background: var(--primary);
}

.main-content {
  flex: 1;
  margin-left: 280px;
  padding: 2rem;
}

/* Dashboard Cards */
.stat-cards {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.stat-card {
  background: var(--white);
  padding: 1.5rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.stat-card .icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1rem;
  font-size: 1.5rem;
}

.stat-card .icon.primary {
  background: rgba(99, 102, 241, 0.1);
  color: var(--primary);
}
.stat-card .icon.success {
  background: rgba(34, 197, 94, 0.1);
  color: var(--success);
}
.stat-card .icon.warning {
  background: rgba(245, 158, 11, 0.1);
  color: var(--warning);
}
.stat-card .icon.danger {
  background: rgba(239, 68, 68, 0.1);
  color: var(--danger);
}

.stat-card .value {
  font-size: 2rem;
  font-weight: 800;
  margin-bottom: 0.25rem;
}

.stat-card .label {
  color: var(--gray);
  font-size: 0.875rem;
}

/* Progress Bar */
.progress {
  height: 8px;
  background: var(--light);
  border-radius: 4px;
  overflow: hidden;
}

.progress-bar {
  height: 100%;
  background: var(--primary);
  border-radius: 4px;
  transition: width 0.3s ease;
}

.progress-bar.success {
  background: var(--success);
}

/* Learning Interface */
.learn-layout {
  display: grid;
  grid-template-columns: 320px 1fr;
  min-height: 100vh;
}

.curriculum-sidebar {
  background: var(--white);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  max-height: 100vh;
  position: sticky;
  top: 0;
}

.curriculum-header {
  padding: 1.5rem;
  border-bottom: 1px solid var(--border);
}

.section-item {
  border-bottom: 1px solid var(--border);
}

.section-header {
  padding: 1rem 1.5rem;
  background: var(--light);
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.lesson-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.875rem 1.5rem;
  border-bottom: 1px solid var(--border);
  cursor: pointer;
  transition: background 0.2s;
}

.lesson-item:hover {
  background: var(--light);
}

.lesson-item.active {
  background: rgba(99, 102, 241, 0.1);
  border-left: 3px solid var(--primary);
}

.lesson-item.completed .check {
  color: var(--success);
}

.lesson-content {
  flex: 1;
  padding: 2rem;
  overflow-y: auto;
}

.video-container {
  position: relative;
  background: var(--dark);
  border-radius: var(--radius);
  overflow: hidden;
  margin-bottom: 2rem;
}

.video-container video {
  width: 100%;
  display: block;
}

/* Forms */
.form-group {
  margin-bottom: 1.5rem;
}

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 600;
  color: var(--dark);
}

.form-control {
  width: 100%;
  padding: 0.875rem 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 1rem;
  transition: border-color 0.2s, box-shadow 0.2s;
}

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

textarea.form-control {
  min-height: 120px;
  resize: vertical;
}

/* Alerts */
.alert {
  padding: 1rem 1.5rem;
  border-radius: var(--radius-sm);
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.alert-success {
  background: rgba(34, 197, 94, 0.1);
  color: #166534;
  border: 1px solid rgba(34, 197, 94, 0.2);
}
.alert-danger {
  background: rgba(239, 68, 68, 0.1);
  color: #991b1b;
  border: 1px solid rgba(239, 68, 68, 0.2);
}
.alert-warning {
  background: rgba(245, 158, 11, 0.1);
  color: #92400e;
  border: 1px solid rgba(245, 158, 11, 0.2);
}
.alert-info {
  background: rgba(14, 165, 233, 0.1);
  color: #075985;
  border: 1px solid rgba(14, 165, 233, 0.2);
}

/* Tables */
.table {
  width: 100%;
  border-collapse: collapse;
  background: var(--white);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.table th,
.table td {
  padding: 1rem 1.25rem;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.table th {
  background: var(--light);
  font-weight: 600;
  color: var(--dark);
}

.table tbody tr:hover {
  background: var(--light);
}

/* Badges */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.75rem;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: 20px;
}

.badge-primary {
  background: rgba(99, 102, 241, 0.1);
  color: var(--primary);
}
.badge-success {
  background: rgba(34, 197, 94, 0.1);
  color: var(--success);
}
.badge-warning {
  background: rgba(245, 158, 11, 0.1);
  color: var(--warning);
}
.badge-danger {
  background: rgba(239, 68, 68, 0.1);
  color: var(--danger);
}

/* Avatar */
.avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  object-fit: cover;
}

.avatar-lg {
  width: 80px;
  height: 80px;
}
.avatar-sm {
  width: 32px;
  height: 32px;
}

/* Footer */
.footer {
  background: var(--dark);
  color: var(--gray-light);
  padding: 4rem 0 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer h4 {
  color: var(--white);
  margin-bottom: 1.5rem;
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 0.75rem;
}

.footer-links a {
  color: var(--gray-light);
  text-decoration: none;
  transition: color 0.2s;
}

.footer-links a:hover {
  color: var(--white);
}

.footer-bottom {
  padding-top: 2rem;
  border-top: 1px solid var(--dark-light);
  text-align: center;
  font-size: 0.875rem;
}

/* Utilities */
.text-center {
  text-align: center;
}
.text-primary {
  color: var(--primary);
}
.text-success {
  color: var(--success);
}
.text-muted {
  color: var(--gray);
}
.mb-1 {
  margin-bottom: 0.5rem;
}
.mb-2 {
  margin-bottom: 1rem;
}
.mb-3 {
  margin-bottom: 1.5rem;
}
.mb-4 {
  margin-bottom: 2rem;
}
.mt-auto {
  margin-top: auto;
}
.d-flex {
  display: flex;
}
.align-center {
  align-items: center;
}
.justify-between {
  justify-content: space-between;
}
.gap-1 {
  gap: 0.5rem;
}
.gap-2 {
  gap: 1rem;
}