✨ Customize website's scrollbar like Mac OS. Not supports in Firefox and IE.

customize-scrollbar.css

/* Customize website's scrollbar like Mac OS
Not supports in Firefox and IE */

/* total width */
body::-webkit-scrollbar {
    background-color: #fff;
    width: 16px;
}

/* background of the scrollbar except button or resizer */
body::-webkit-scrollbar-track {
    background-color: #fff;
}

/* scrollbar itself */
body::-webkit-scrollbar-thumb {
    background-color: #babac0;
    border-radius: 16px;
    border: 4px solid #fff;
}

/* set button(top and bottom of the scrollbar) */
body::-webkit-scrollbar-button {
    display:none;
}

merged the content of the discussion in one css :

/* Customize website's scrollbar like Mac OS
Not supports in Firefox and IE */
.scrollbar {
  overflow: overlay
}

/* total width */
.scrollbar::-webkit-scrollbar {
  background-color: rgba(0,0,0,0);
  width: 16px;
  height: 16px;
  z-index: 999999;
}

/* background of the scrollbar except button or resizer */
.scrollbar::-webkit-scrollbar-track {
  background-color: rgba(0,0,0,0);
}

/* scrollbar itself */
.scrollbar::-webkit-scrollbar-thumb {
  background-color: rgba(0,0,0,0);
  border-radius:16px;
  border:0px solid #fff;
}

/* set button(top and bottom of the scrollbar) */
.scrollbar::-webkit-scrollbar-button {
  display:none;
}


/* scrollbar when element is hovered */
.scrollbar:hover::-webkit-scrollbar-thumb {
  background-color: #a0a0a5;
  border:4px solid #fff;
}

/* scrollbar when scrollbar is hovered */
.scrollbar::-webkit-scrollbar-thumb:hover {
    background-color:#a0a0a5;
    border:4px solid #f4f4f4
}

add 'scrollbar' class to the elements that should have the custom scrollbar (@alioshr).

For those wanting to test this on macOS set the scrollbar always visible. If your scrollbar hides when your mouse does not hover the element than it is working

/* Customize website's scrollbar like Mac OS
Not supports in Firefox and IE */
.scrollbar {
overflow: overlay
}

/* total width */
.scrollbar::-webkit-scrollbar {
background-color: rgba(0,0,0,0);
width: 16px;
height: 16px;
z-index: 999999;
}

/* background of the scrollbar except button or resizer */
.scrollbar::-webkit-scrollbar-track {
background-color: rgba(0,0,0,0);
}

/* scrollbar itself */
.scrollbar::-webkit-scrollbar-thumb {
background-color: rgba(0,0,0,0);
border-radius:16px;
border:0px solid #fff;
}

/* set button(top and bottom of the scrollbar) */
.scrollbar::-webkit-scrollbar-button {
display:none;
}

/* scrollbar when element is hovered */
.scrollbar:hover::-webkit-scrollbar-thumb {
background-color: #a0a0a5;
border:4px solid #fff;
}

/* scrollbar when scrollbar is hovered */
.scrollbar::-webkit-scrollbar-thumb:hover {
background-color:#a0a0a5;
border:4px solid #f4f4f4
}

This works! thanks!

Chrome 114, overflow: overlay is removed.

@zhnoah , you should use scrollbar-gutter: stable instead of overflow: overlay