CSS ripple effect on Hover?

Question

I have a button where I'd like a slightly transparent overlay to 'glide through' the button on hover. There is something called the 'ripple effect' that you usually can achieve by clicking on a button.

Like here: https://codepen.io/tomma5o/pen/zwyKya

const isMobile = window.navigator.userAgent.match(/Mobile/) && window.navigator.userAgent.match(/Mobile/)[0] === "Mobile";
const event = isMobile ? "touchstart" : "click";

const button = document.querySelectorAll('*[data-animation="ripple"]'),
  container = document.querySelector(".container");

for (var i = 0; i < button.length; i++) {
  const currentBtn = button[i];

  currentBtn.addEventListener(event, function(e) {

    e.preventDefault();
    const button = e.target,
      rect = button.getBoundingClientRect(),
      originalBtn = this,
      btnHeight = rect.height,
      btnWidth = rect.width;
    let posMouseX = 0,
      posMouseY = 0;

    if (isMobile) {
      posMouseX = e.changedTouches[0].pageX - rect.left;
      posMouseY = e.changedTouches[0].pageY - rect.top;
    } else {
      posMouseX = e.x - rect.left;
      posMouseY = e.y - rect.top;
    }

    const baseCSS = `position: absolute;
                                                width: ${btnWidth * 2}px;
                                                height: ${btnWidth * 2}px;
                                                transition: all linear 700ms;
                                                transition-timing-function:cubic-bezier(0.250, 0.460, 0.450, 0.940);
                                                border-radius: 50%;
                                                background: var(--color-ripple);
                                                top:${posMouseY - btnWidth}px;
                                                left:${posMouseX - btnWidth}px;
                                                pointer-events: none;
                                                transform:scale(0)`

    var rippleEffect = document.createElement("span");
    rippleEffect.style.cssText = baseCSS;

    //prepare the dom
    currentBtn.style.overflow = "hidden";
    this.appendChild(rippleEffect);

    //start animation
    setTimeout(function() {
      rippleEffect.style.cssText = baseCSS + `transform:scale(1); opacity: 0;`;
    }, 5);

    setTimeout(function() {
      rippleEffect.remove();
      //window.location.href = currentBtn.href;
    }, 700);
  })
}

:root {
  /* if u want to change the color of
         * the ripple change this value
        */
  --color-ripple: rgba(255, 255, 255, 0.8);
}

body {
  background: #36353c;
}

.container {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  height: 50px;
  width: 200px;
  margin: auto;
}

*[data-animation="ripple"] {
  position: relative;
  /*Position relative is required*/
  height: 100%;
  width: 100%;
  display: block;
  outline: none;

  :root {
    /* if u want to change the color of
         * the ripple change this value
        */
    --color-ripple: rgba(255, 255, 255, 0.8);
  }

  body {
    background: #36353c;
  }

  .container {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    height: 50px;
    width: 200px;
    margin: auto;
  }

  *[data-animation="ripple"] {
    position: relative;
    /*Position relative is required*/
    height: 100%;
    width: 100%;
    display: block;
    outline: none;
    padding: 20px;
    color: #fff;
    text-transform: uppercase;
    background: linear-gradient(135deg, #e570e7 0%, #79f1fc 100%);
    box-sizing: border-box;
    text-align: center;
    line-height: 14px;
    font-family: roboto, helvetica;
    font-weight: 200;
    letter-spacing: 1px;
    text-decoration: none;
    box-shadow: 0 5px 3px rgba(0, 0, 0, 0.3);
    cursor: pointer;
    /*border-radius: 50px;*/
    -webkit-tap-highlight-color: transparent;
  }

  *[data-animation="ripple"]:focus {
    outline: none;
  }

  *[data-animation="ripple"]::selection {
    background: transparent;
    pointer-events: none;
  }

  padding: 20px;
  color: #fff;
  text-transform: uppercase;
  background: linear-gradient(135deg, #e570e7 0%, #79f1fc 100%);
  box-sizing: border-box;
  text-align: center;
  line-height: 14px;
  font-family: roboto,
  helvetica;
  font-weight: 200;
  letter-spacing: 1px;
  text-decoration: none;
  box-shadow: 0 5px 3px rgba(0, 0, 0, 0.3);
  cursor: pointer;
  /*border-radius: 50px;*/
  -webkit-tap-highlight-color: transparent;
}

*[data-animation="ripple"]:focus {
  outline: none;
}

*[data-animation="ripple"]::selection {
  background: transparent;
  pointer-events: none;
}

<div class="container">
  <a data-animation="ripple">Click Me</a>
</div>

Is it possible to achieve something similar without having to click on the button but just hovering over it?

Answer 1

Replace line 2 of JS:

const event = isMobile ? "touchstart" : "click";

with:

const event = isMobile ? "touchstart" : "mouseover";

That would do the job.

Answer 2

If you want the ripple origin to be fixed (e.g. from the middle) instead of from wherever the mouse enters, the answer is much simpler and requires no javascript: just stack a semi-transparent rounded pseudo-element and animate the scale on hover.

body {
	background: #36353c;
}

.container {
	position: absolute;
	top: 0;
	left: 0;
	right: 0;
	bottom: 0;
	height: 50px;
	width: 200px;
	margin: auto;
}
.ripple{
	position: relative; /*Position relative is required*/
	height: 100%;
	width: 100%;
	display: block;
	outline: none;
	padding: 20px;
	color: #fff;
	text-transform: uppercase;
	background: linear-gradient(135deg, #e570e7 0%,#79f1fc 100%);
	box-sizing: border-box;
	text-align: center;
	line-height: 14px;
	font-family: roboto, helvetica;
	font-weight: 200;
	letter-spacing: 1px;
	text-decoration: none;
	box-shadow: 0 5px 3px rgba(0, 0, 0, 0.3);
	cursor: pointer;
	overflow:hidden;
}

.ripple:hover:before{
	animation: ripple 1s ease;
}

.ripple:before{
	content:"";
	position:absolute; top:0; left:0;
	width:100%; height:100%;
  background-color:rgba(255, 255, 255, 0.7);
  border-radius:50%;
	transform:scale(0);
}

@keyframes ripple{
	from{transform:scale(0); opacity:1;}
	to{transform:scale(3);opacity:0;}
}

<div class="container">
	<a class="ripple">Hover Me</a>
</div>