Error in the browser and a strange reaction to change CSS how to solve?

Hi all.

There is a problem and I do not understand what it is. Something is broken in the layout or problems with the browser. Did everything according to the tutorial video. Everything worked. Editor brackets. Further, to clean a bit the code, sent it to VSC and the TM preterm on it went, back stuck in the brackets and the browser became weird to work with.

In the developer dashboard appeared error: Failed to load resource: the server responded with a status of 404 (Not Found)
and Cannot GET /favicon.ico.

The page in live view reacts strangely to change the code in css, namely the separate edits perceives no individual. Remove entire blocks of markup, the idea must divide the blocks, and they remain in their original locations.

Change margin blocks apart, completely remove the margin - 15px remain original. Prompt where to dig and why this happens?
April 4th 20 at 00:48
0 answer

Find more questions by tags HTMLBrowsers