Do projects often use the scroll bar, sometimes to set overflow div invalid.
Encountered such a problem, just check it in F12 Elements panel to set the width and height of the overflow element is greater than the width and height of the parent element.
(Overflow set an invalid reason most of them are taller than wider width and height of the parent element)
Solution: only need to set the width and height of an element overflow parent element of less than or equal to the width and height