100% height with scroll

Option 1

Make the body fixed.

body {
	overflow: hidden;
	position: fixed;
	left: 0;
	width: 100%;
}

Option 2

Add an extra height to the HTML tag.

html {
	height: 100%;
}

body {
	overflow-y: hidden;
	height: 100%;
}

Option 3

We can add an extra attribute to make things work in Webkit browsers.

body {
	overflow: hidden;
}

.overlay {
	position: fixed;
	top: 0;
	left: 0;
	overflow-y: scroll;
	width: 100%;
	height: 100vh;
overflow-scrolling: touch;
}