Responsive profile card page, using HTML, CSS

It's my first challenge at Frontmentor :)

1. It looks so, as the profile card in design has a very light shadow, but I couldn't make the shadow so light. I played with numbers and colors, but it was always too large, too visible. How to make the light almost invisible shadow?

2. It took a lot of time to put the svg-circles in the background to the right place. First I tried to use percentage values in background-position. It works with images so, that when I write "background-position: 100% 100%", image goes to the right bottom corner. But SVG-files behave in a different way, and I couldn't find out why. When I made browser window smaller (from desktop to tablet/mobile size), the circle moved to the right side (I expected moving to the left side). So I could achieve the goal, using concrete pixel values and media query. But if someone knows, where to read about SVG percentage positioning behaviour, I would be glad to read.