User Experience improvements

I made a few changes to improve the website navigability with special emphasis on the mobile version. The improvements were made in a few key areas:

• Navigation - the navigation bar is now sticky and will always stay on top even when scrolling down. This should allow you to access any section of the website without having to scroll up.
• Clarity - the menus got a gloss effect to make them easier to read. The only exception is if you use the Firefox browser as it does not support the feature yet, but should soon. The options inside the menu also got a new border so it's easier to understand the hit areas.
• Consistency - The mobile menu is now using a black transparent background to make it consistent with the normal version.
• Accessibility - The hamburger menu (3 horizontal lines) available on the mobile version has now been moved to the right (sorry lefties!). On the left I have now added an icon to go directly to the home page.

I hope you like the changes!