Hello, @TFS,
Page width is based on the screen you are viewing. There is no specific resolution that I can tell you. Try to set an image on the background then set the width of the image using CSS code to “100%” and then it will cover the screen from left to right.
Check this link to understand how the background image will work: https://www.w3schools.com/cssref/tryit.php?filename=trycss_background-image
Regards 8Themes Team.