100vw causing horizontal overflow, but only if more than one?

Question

Say you have this:

html, body {margin: 0; padding: 0}
.box {width: 100vw; height: 100vh}

Screen 1

You

Answer 1

*,
html,
body {
  margin: 0;
  padding: 0;
  overflow: hidden;/*add This*/ 
}
/*and enjoy ^_^ */