Magazine Basic theme: Help with Left sidebar and right sidebar

Magazine Basic is great! I want to make a child theme, but won’t do that until I have the Magazine Basic looking the way I want it.

My only problem I am having is adding Widgets to the Left sidebar and right sidebar. I have been looking at every post about Magazine Basic to try to understand how to adjust the left side bar and the right, but I keep getting confused when one side is adjusted the other side seems to move out of place. Please tell me how do I find the Left side bar: widget-1 and widget-2 and adjust the picture( left amazon pic) to stay inside the box in style.css. Then find the Right Sidebar: widget-1 adjust the picture to stay inside the box and the box to just fit the widget to the far right only,(I dont want it to be twice as wide as the pic. I cannot find these according to the other posts I am reading. Some posts are from 2-5 years ago and it seems the style.css may have changed since then and the phrase @import keeps popping up in the posts I have read. So I know I need some much up-to-date info on Magazine Basic.

My site is Smart Internet Things

Please help me find where to adjust these in the style.css.
Thanks for any response pointing me in the right direction so they won’t move. I want the right side bar(the amazon pic) to move to the far right and stay there and to only be the size of the pic. It is much too wide on the right sidebar. And since it is 4am in the morning all of this might not sound very clear. I need to get some sleep. I hope I have made it clear.. Thanks for a response..