/* Teaching Content Management Platform - Styles */

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

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  color: #333;
}

.teaching-platform {
  min-height: 100vh;
  background: rgba(255, 255, 255, 0.95);
}

/* Header Styles */
.platform-header {
  background: linear-gradient(135deg, #2c3e50 0%, #3498db 100%);
  color: white;
  padding: 1.5rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.platform-header h1 {
  font-size: 2rem;
  font-weight: 300;
}

.platform-header button {
  background: #e74c3c;
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: 25px;
  cursor: pointer;
  font-size: 1rem;
  transition: all 0.3s ease;
}

.platform-header button:hover {
  background: #c0392b;
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

/* Main Content */
.platform-content {
  padding: 2rem;
  max-width: 1400px;
  margin: 0 auto;
}

/* Add Course Form */
.add-course-form {
  background: white;
  padding: 2rem;
  border-radius: 10px;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  margin-bottom: 2rem;
  border: 2px solid #3498db;
}

.add-course-form h3 {
  color: #2c3e50;
  margin-bottom: 1rem;
  font-size: 1.5rem;
}

.add-course-form input,
.add-course-form textarea {
  width: 100%;
  padding: 0.75rem;
  margin-bottom: 1rem;
  border: 2px solid #ecf0f1;
  border-radius: 5px;
  font-size: 1rem;
  transition: border-color 0.3s ease;
}

.add-course-form input:focus,
.add-course-form textarea:focus {
  outline: none;
  border-color: #3498db;
}

.add-course-form button {
  background: #27ae60;
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: 5px;
  cursor: pointer;
  font-size: 1rem;
  transition: all 0.3s ease;
}

.add-course-form button:hover {
  background: #229954;
  transform: translateY(-1px);
}

/* Main Layout */
.main-layout {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 2rem;
  align-items: start;
}

/* Course Section */
.course-section h2 {
  color: #2c3e50;
  margin-bottom: 1.5rem;
  font-size: 1.8rem;
}

.course-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
}

.course-card {
  background: white;
  padding: 1.5rem;
  border-radius: 10px;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  cursor: pointer;
  transition: all 0.3s ease;
  border: 2px solid transparent;
}

.course-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 15px rgba(0, 0, 0, 0.2);
  border-color: #3498db;
}

.course-card h3 {
  color: #2c3e50;
  margin-bottom: 0.5rem;
  font-size: 1.3rem;
}

.course-card p {
  color: #7f8c8d;
  margin-bottom: 1rem;
  line-height: 1.5;
}

.course-meta {
  display: flex;
  justify-content: space-between;
  color: #95a5a6;
  font-size: 0.9rem;
}

/* Course Details */
.course-details {
  background: white;
  padding: 2rem;
  border-radius: 10px;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.course-details h2 {
  color: #2c3e50;
  margin-bottom: 1rem;
  font-size: 2rem;
}

.course-details p {
  color: #7f8c8d;
  margin-bottom: 1rem;
  line-height: 1.6;
}

.course-content {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 2rem;
  margin-top: 2rem;
}

/* Lesson List */
.lesson-list h3 {
  color: #2c3e50;
  margin-bottom: 1rem;
  font-size: 1.3rem;
}

.lesson-item {
  background: #f8f9fa;
  padding: 1rem;
  margin-bottom: 0.5rem;
  border-radius: 5px;
  cursor: pointer;
  transition: all 0.3s ease;
  border-left: 4px solid transparent;
}

.lesson-item:hover {
  background: #e9ecef;
  border-left-color: #3498db;
}

.lesson-item.selected {
  background: #3498db;
  color: white;
  border-left-color: #2980b9;
}

.lesson-item h4 {
  margin-bottom: 0.25rem;
  font-size: 1.1rem;
}

.lesson-item p {
  font-size: 0.9rem;
  opacity: 0.8;
}

/* Content Editor */
.content-editor {
  background: #f8f9fa;
  padding: 1.5rem;
  border-radius: 5px;
  min-height: 300px;
}

.editor-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
}

.editor-header h3 {
  color: #2c3e50;
  font-size: 1.3rem;
}

.editor-header button {
  background: #3498db;
  color: white;
  border: none;
  padding: 0.5rem 1rem;
  border-radius: 5px;
  cursor: pointer;
  font-size: 0.9rem;
  transition: background 0.3s ease;
}

.editor-header button:hover {
  background: #2980b9;
}

.content-editor textarea {
  width: 100%;
  padding: 1rem;
  border: 2px solid #ecf0f1;
  border-radius: 5px;
  font-size: 1rem;
  font-family: inherit;
  resize: vertical;
  margin-bottom: 1rem;
}

.content-editor textarea:focus {
  outline: none;
  border-color: #3498db;
}

.content-editor button {
  background: #27ae60;
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: 5px;
  cursor: pointer;
  font-size: 1rem;
  transition: all 0.3s ease;
}

.content-editor button:hover {
  background: #229954;
  transform: translateY(-1px);
}

.lesson-content p {
  color: #2c3e50;
  line-height: 1.6;
  font-size: 1rem;
}

/* Responsive Design */
@media (max-width: 1024px) {
  .main-layout {
    grid-template-columns: 1fr;
  }
  
  .course-content {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .platform-header {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }
  
  .platform-content {
    padding: 1rem;
  }
  
  .course-grid {
    grid-template-columns: 1fr;
  }
  
  .add-course-form {
    padding: 1rem;
  }
}

@media (max-width: 480px) {
  .platform-header h1 {
    font-size: 1.5rem;
  }
  
  .course-details,
  .add-course-form {
    padding: 1rem;
  }
}