First challenge I didn´t solve is that I wanted my navigation links in all pages, excluding my main page, to stay fixed on the top side of the screen when I scroll down. I tryed to do it by adding values in css such as - position: fixed and z-index: 9999 – which I googled. However, the default position of my nav links on page is not the top of the page and when I scrolled, the bar with links didn´t go up to the top of the page as desired, but stayed fixated on it´s default position, while the text and body of the page was scrolling besides it.
         Second challenge is that I didn´t manage to make social sites buttons to be responsive enough. They don´t scale together with the image or pages, but separately. I failed to center them inside the "main" block element.
         On the other hand, I managed to complete many challenges that this week´s assignment brought. One of them is that I came up with the way to position linked images over another image using fixated position (even thought the scaling isn´t perfect, just as I mentioned earlier). The approximate size of my website is 1700KB and you can find the screen dump here.