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CSS

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JavaScript

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HTML 

              
                <div class="title">CSS3 Filters</div>
<div class="error"></div>
<div class="container">
  <div class="switch white">
    <input type="radio" name="switch" id="switch-off" value = "off" />
    <input type="radio" name="switch" id="switch-on" checked value="on"/>
    <label for="switch-off">Off</label>
    <label for="switch-on">On</label>
    <span class="toggle"></span>
  </div>
</div>

<ul class="social-icons filter">
  <li class="icon icon-facebook"></li>
  <li class="icon icon-twitter"></li>
  <li class="icon icon-gplus"></li>
  <li class="icon icon-pintrest"></li>
  <li class="icon icon-youtube"></li>
</ul>
!

CSS 

              
                body {
  background: #F1F1F1;
}

.title, .error {
  margin: auto;
  margin-bottom: 5%;
  text-align: center;
  font-family: "Lato", sans-serif;
}

.title {
  color: #444;
  font-size: 4em;
}

.error {
  color: #ED4337;
  font-size: 1.5em;
}

/* Social Icons Styles */
.social-icons {  
  margin-top: 10%;
  text-align: center;
  margin-left: -10px;
}

.icon {
  display: inline-block;
  height: 128px;
  width: 128px;
  background-repeat: no-repeat;
  background-size: contain;
}

.icon:hover {
  cursor: pointer;
}

.icon,
.icon:hover {
  -webkit-transition: all .5s ease;
     -moz-transition: all .5s ease;
      -ms-transition: all .5s ease;
       -o-transition: all .5s ease;
          transition: all .5s ease;
}

.social-icons.filter .icon {
  -webkit-filter: grayscale(1);
     -moz-filter: grayscale(1);
      -ms-filter: grayscale(1); /* Just in Case IE provides it with prefix. */
          filter: grayscale(1);
}

.social-icons.filter .icon:hover {
  -webkit-filter: grayscale(0);
     -moz-filter: grayscale(0);
      -ms-filter: grayscale(0); /* Just in Case IE provides it with prefix. */
          filter: grayscale(0);
}

.social-icons.filter .icon-facebook {
  background-image: url("https://i.imgur.com/dBSL6N2.png"); /* Color Icon */
}

.social-icons.nofilter .icon-facebook {
  background-image: url("https://i.imgur.com/TtcsSBg.png"); /* Fallback B&W Icon*/
}

.social-icons.nofilter .icon-facebook:hover {
  background-image: url("https://i.imgur.com/dBSL6N2.png"); /* Fallback Color Icon */
}

.social-icons.filter .icon-twitter {
  background-image: url("https://i.imgur.com/C6hmtgp.png"); /* Color Icon */
}

.social-icons.nofilter .icon-twitter {
  background-image: url("https://i.imgur.com/Jm7GSTD.png"); /* Fallback B&W Icon */
}

.social-icons.nofilter .icon-twitter:hover {
  background-image: url("https://i.imgur.com/C6hmtgp.png"); /* Fallback Color Icon */
}

.social-icons.filter .icon-gplus {
  background-image: url("https://i.imgur.com/Ks4TG00.png");
}

.social-icons.nofilter .icon-gplus {
  background-image: url("https://i.imgur.com/kEEKHE0.png");
}

.social-icons.nofilter .icon-gplus:hover {
  background-image: url("https://i.imgur.com/Ks4TG00.png");
}

.social-icons.filter .icon-pintrest {
  background-image: url("https://i.imgur.com/BYJUbtI.png");
}

.social-icons.nofilter .icon-pintrest {
  background-image: url("https://i.imgur.com/eMgJzz2.png");
}

.social-icons.nofilter .icon-pintrest:hover {
  background-image: url("https://i.imgur.com/BYJUbtI.png");
}

.social-icons.filter .icon-youtube {
  background-image: url("https://i.imgur.com/ZQiLpek.png");
}

.social-icons.nofilter .icon-youtube {
  background-image: url("https://i.imgur.com/rFys3w0.png");
}

.social-icons.nofilter .icon-youtube:hover {
  background-image: url("https://i.imgur.com/ZQiLpek.png");
}

/* Switch Styles */

.container {
  margin: auto;
	height: 64px;
	width: 160px;
}

.switch {
  margin-left: 10px;
}

.switch input {
    font-family: inherit;
    font-size: 100%;
    line-height: normal;
    margin: 0;
}

.switch input[type="radio"] {
    box-sizing: border-box;
    padding: 0;
}

.switch {
	background: #fff;
	border-radius: 32px;
	display: block;
	height: 64px;
	position: relative;
	width: 160px;
}

.switch label {
	color: #444;
  font: 100%/1.5em "Lato", sans-serif;
	font-size: 48px;
	font-weight: 300;
	line-height: 64px;
	text-transform: uppercase;
	-webkit-transition: color .2s ease;
	   -moz-transition: color .2s ease;
    	-ms-transition: color .2s ease;
	     -o-transition: color .2s ease;
	        transition: color .2s ease;
	width: 100px;
}

.switch label:nth-of-type(1) {
	left: -75%;
	position: absolute;
	text-align: right;
}

.switch label:nth-of-type(2) {
	position: absolute;
  right: -75%;
	text-align: left;
}

.switch input {
	height: 64px;
	left: 0;
	opacity: 0;
	position: absolute;
	top: 0;
	width: 160px;
	z-index: 2;
}

.switch input:checked~label:nth-of-type(1) { color: #444; }
.switch input:checked~label:nth-of-type(2) { color: #808080; }

.switch input~:checked~label:nth-of-type(1) { color: #808080; }
.switch input~:checked~label:nth-of-type(2) { color: #444; }

.switch input:checked~.toggle {
	left: 4px;
}

.switch input~:checked~.toggle {
	left: 100px;
}

.switch input:checked {
	z-index: 0;
}

.toggle {
	background: #4a4a4a;
	border-radius: 50%;
	height: 56px;
	left: 0;
	position: absolute;
	top: 4px;
	-webkit-transition: left .2s ease;
	   -moz-transition: left .2s ease;
	    -ms-transition: left .2s ease;
	     -o-transition: left .2s ease;
	        transition: left .2s ease;
	width: 56px;
	z-index: 1;
}
!

JS 

              
                /**
Social Icons (CSS Filters/ No Filters).

Social icons on-hover grayscale effect with CSS3 filters applied and with no filter applied. Toggle Switch courtesy: Marco Biedermann (https://codepen.io/m412c0).

@author: Kushal Pandya (http://doublslash.com)

Following JS code is just for feature-detection and toggling filters.

**/

// Patch Modernizr to detect CSS Filters Support
Modernizr.addTest('cssfilters', function() {
    var el = document.createElement('div');
    el.style.cssText = Modernizr._prefixes.join('filter' + ':blur(2px); ');
    return !!el.style.length && ((document.documentMode === undefined || document.documentMode > 9));
});;

var socialIconsList = $("ul.social-icons");

// Check CSS Filters support
if (!Modernizr.cssfilters)
{
  $("#switch-off").prop('checked',true);
  $("#switch-on").prop('disabled', true);
  $(".error").text("Sorry! CSS Filters are not supported in your browser. We're using fallback mode.");
  socialIconsList.addClass("nofilter");
}

$("input[type='radio']").on("click", function(e) {
  if ($(this).val() === "on")
  {
    socialIconsList.removeClass("nofilter").addClass("filter");
  }
  else
  {
    socialIconsList.removeClass("filter").addClass("nofilter");
  }
});
!
999px

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