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<div class="SideScroller">
<div class="SideScroller__wrap">
<div class="SideScroller__foreground"></div>
<div class="SideScroller__mask">
<div class="SideScroller__line">
<div class="SideScroller__handle">
<svg role="img" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512"><path fill="currentColor" d="M377.941 169.941V216H134.059v-46.059c0-21.382-25.851-32.09-40.971-16.971L7.029 239.029c-9.373 9.373-9.373 24.568 0 33.941l86.059 86.059c15.119 15.119 40.971 4.411 40.971-16.971V296h243.882v46.059c0 21.382 25.851 32.09 40.971 16.971l86.059-86.059c9.373-9.373 9.373-24.568 0-33.941l-86.059-86.059c-15.119-15.12-40.971-4.412-40.971 16.97z"></path></svg>
</div>
</div>
</div>
</div>
</div>
$c-handle: #FFFFFF
$c-bg: #afb69e
=square($n)
height: $n
width: $n
=circle($n)
+square($n)
border-radius: 50%
=center
position: absolute
top: 50%
left: 50%
transform: translate(-50%, -50%)
=cover
position: absolute
top: 0
left: 0
bottom: 0
right: 0
body
background: $c-bg
margin: 0
// - - - -
.SideScroller
padding: 1rem
max-width: 900px
margin: 0 auto
height: 15rem
@media (min-width: 576px)
height: 20rem
@media (min-width: 768px)
height: 30rem
&__wrap
height: 100%
position: relative
background: url(https://garethweaver.com/codepen/images/shark-1.jpg) no-repeat center center
background-size: cover
&__foreground
+cover
background: url(https://garethweaver.com/codepen/images/shark-2.jpg) no-repeat center center
background-size: cover
&__mask
height: 100%
position: relative
&__line
height: 100%
width: 2px
background: $c-handle
position: absolute
top: 0
right: 0
bottom: 0
&__handle
+circle(2rem)
+center
background: $c-handle
position: absolute
padding: 10%
svg
+square(1.5rem)
+center
class SideScroller {
constructor(selector) {
this.elmClassName = selector.split('.').pop()
this.wrap = document.getElementsByClassName(`${this.elmClassName}__wrap`)[0]
this.handle = document.getElementsByClassName(`${this.elmClassName}__handle`)[0]
this.mask = document.getElementsByClassName(`${this.elmClassName}__mask`)[0]
this.fg = document.getElementsByClassName(`${this.elmClassName}__foreground`)[0]
this.pos = 50
this.create()
}
create() {
this.handle.addEventListener('mousedown', this.drag)
this.handle.addEventListener('touchstart', this.drag)
window.addEventListener('resize', this.resizeHandler)
this.setPosition()
}
drag = e => {
e.preventDefault()
document.addEventListener('mousemove', this.dragHandler)
document.addEventListener('touchmove', this.dragHandler)
document.addEventListener('mouseup', this.stopDragHandler)
document.addEventListener('touchend', this.stopDragHandler)
}
resizeHandler = e => {
this.setPosition()
}
dragHandler = e => {
let percent = this.getPercent(e, this.wrap)
if (percent < 0) {
percent = 0
} else if (percent > 100) {
percent = 100
}
this.setPosition(percent)
}
stopDragHandler = e => {
document.removeEventListener('mousemove', this.dragHandler)
document.removeEventListener('mouseup', this.stopDragHandler)
}
getPercent(evt, elm) {
let ref = evt.touches
? evt.touches[0].pageX
: evt.pageX
let rect = elm.getBoundingClientRect()
return ((ref - rect.left) / rect.width) * 100
}
setPosition(percent = this.pos) {
this.pos = percent
this.mask.style.width = percent + '%'
const clip = `inset(0 0 0 ${this.wrap.offsetWidth * percent / 100}px)`
this.fg.style.clipPath = clip
this.fg.style.webkitClipPath = clip
}
}
new SideScroller('.SideScroller')
Also see: Tab Triggers