Here are the changes I made to the original HTML to enhance its aesthetic appeal and overall structure:

### 1. **Inline Styles for Improved Layout**
   - Added inline styles throughout the HTML to improve spacing, alignment, and overall aesthetics without requiring a separate CSS file.

### 2. **Navigation Bar Enhancements**
   - Improved spacing and alignment in the navigation bar for better readability.
   - Added hover effects to links for interactivity.
   - Styled buttons for "Sign Up" and "Login" to make them more visually appealing.

### 3. **Hero Section Styling**
   - Applied a gradient background to the hero section for a modern look.
   - Increased font sizes and adjusted padding for a more impactful introduction.

### 4. **Course Recommendations Section**
   - Added a flexbox layout to display course cards responsively.
   - Styled course cards with shadows, borders, and hover effects to create depth.
   - Used consistent sizing for course thumbnails to enhance visual uniformity.

### 5. **Contact Us Section**
   - Centered the contact form and adjusted padding for a clean layout.
   - Added styling to input fields and the submit button for a cohesive design.

### 6. **Footer Enhancements**
   - Structured the footer into two columns for important links and social media icons.
   - Improved the appearance of footer links and social media icons for better accessibility and engagement.

### 7. **Overall Aesthetic Improvements**
   - Used a cohesive color scheme throughout the page, ensuring consistency between sections.
   - Enhanced typography with appropriate font sizes and weights to improve readability and hierarchy.

These changes contribute to a more modern, elegant, and user-friendly interface, enhancing the overall user experience.