feat: add personal sections and styling to portfolio webpage

[martasskv5]

This pull request introduces a personal portfolio website with new sections, styling updates, and interactive functionality. The changes include adding new content to the index.html file, implementing styles for project sections in style.css, and adding interactivity to project elements in script.js.

Content Additions:

• Added new sections to index.html for "About Me," "Projects," and "Contact," including personalized content about the author, a project showcase, and a contact email link.
• Updated the footer to include a copyright notice for "Martin Michalec."

Styling Enhancements:

• Introduced a .project_m class in style.css to style project cards with a green border and light green background. Added an .active class for toggling styles on click, changing the border to red and the background to light red.

Interactivity:

• Added a JavaScript event listener in script.js to toggle the .active class on project elements when clicked, providing visual feedback.