Improvement/improve mobile experience docs

[Edwardvaneechoud]

This pull request updates the docs/quickstart.md file to significantly improve the visual appearance and responsiveness of the Quick Start Guide. The changes focus on making the documentation look better on all devices by using responsive CSS styles, improving readability, and enhancing the user experience for both non-technical and technical users.

Key improvements include:

Responsive and Accessible Styling

• Replaced fixed pixel values with responsive CSS using clamp() and auto-fit for paddings, margins, font sizes, and grid layouts, ensuring the guide looks good on all screen sizes. [1] [2] [3] [4]
• Improved button and card styles for better usability and touch-friendliness, including wider clickable areas and better text alignment. [1] [2]

Enhanced Readability and User Experience

• Updated headings, section dividers, and callout boxes to use more readable font sizes and color contrasts. [1] [2]
• Improved the appearance of code blocks and scrollable containers to ensure code examples are easy to read on mobile devices. [1] [2] [3]

Consistency and Accessibility

• Ensured consistent use of color, border radius, and spacing throughout the document for a more professional look. [1] [2] [3]
• Updated section headings and pro tips to be more prominent and accessible.

Improved Technical and Non-Technical Sections

• Enhanced the "Choose Your Path" grid and both quickstart flows to be more visually distinct and easier to follow for their respective audiences. [1] [2]
• Added scrollable containers for wide code samples and advanced patterns for technical users. [1] [2] [3] [4]

These changes make the Quick Start Guide more modern, readable, and user-friendly, especially on mobile and tablet devices.