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

HTML:

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

CSS:

: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;
}

JS:

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);
    })
}

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.

Hope that helps!

Answer 2

If you want the ripple origin to be fixed (eg 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>