index.html
<!DOCTYPE html>
<meta charset="utf-8">
<style>
body {
width: 720px;
margin: 20px auto 20px auto;
}
#d3 {
outline: 1px red solid;
width: 720px;
overflow: hidden;
}
#d3 div {
width: 5px;
height: 5px;
background-color: white;
outline: 1px black solid;
float: left;
margin: 5px;
display: block;
}
</style>
<p><button id="click">Click me!</button> Built with <a href="https://d3js.org/">D3</a>. A response to Rich Bradshaw’s <a href="//css3.bradshawenterprises.com/demos/speed.php">jQuery <i>vs.</i> CSS transition speed test</a>.
<div id="d3"></div>
<script src="//d3js.org/d3.v3.min.js"></script>
<script>
var div = d3.select("#d3").selectAll("div")
.data(d3.range(48 * 48))
.enter().append("div");
d3.select("#click").on("click", function() {
div
.style("background-color", null)
.style("outline-color", null)
.transition()
.duration(1000)
.style("background-color", "black")
.style("outline-color", "red");
});
</script>