Apply the property box-sizing: border-box; to all of your elements (selector *) so the extra space caused by borders, padding, and margins is then included in the 100% and not added to the 100% (i.e. 100% + 5px border).
Add this line on top of your css, that should prevent scrolling
This question is everywhere and the solution is always the same but it never works for me and I have no idea why! I simply need my div to fill the entire view port without creating a scroll bar. Who knew this would be so difficult. Everyone says to just set body and html margins to zero but this doesn’t work. I still have a vertical scroll bar! I’m getting really frustrated and I would really appreciate some help. Here is the JSFiddle https://jsfiddle.net/davdarobis/d3k4hv6q/23/.