Why does the width of body get narrower?

Question

css

Guys, we need a collective mind. Help me please. I am compiling the page somedia.pro/beta , when the width of the browser window changes, the body changes the width (narrows), although width: 100% is everywhere, and because of this, the width of all blocks narrows (although everything seems to be done correctly in layout). What could be the problem?

Answer 1

Looked body has the size of the viewport, which is expected at width:100%