You sound like someone who is at the beginning of the learning curve. Nothing wrong with that but don't be so hostile. People used tables for positioning and

You sound like someone who is at the beginning of the learning curve. Nothing wrong with that but don't be so hostile. People used tables for positioning and as containers. More data was present compared to whitespace and mobile reduced sites. People had different screensizes back than. How do you deal with that? You take a 3x3 cell. You cut a picture into 9 slices. You take the top, left, right and bottom images and make them a background at 100% width (top/bottom) or height. That is the basics of a simple flexibile container.