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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <div class=IMG>

  <h1 class=IMG_title>
    <span class=IMG_copy-1>Scaling</span>
    <span class=IMG_copy-2>font-size</span>
    <span class=IMG_copy-3>in</span>
    <span class=IMG_copy-4>prop<span>o</span>rtion</span>
    <span class=IMG_copy-5>to an</span>
    <span class=IMG_copy-6>image</span>
    <span class=IMG_copy-7><span>&harr;</span> Resize the window</span>

  <div class=IMG_bg></div>


<section class=credits>

    <li><a target=_blank title="[new window]" href="">Fluid-responsive font-size calculator</a></li>

    <li>Photo: <a target=_blank title="[new window]" href="">Marcus Castro</a></li>
    <li>Real world example: <a target=_blank title="[new window]" href="">Food Love Stories</a></li>
    <li>Dirty 'orrible 'acky <a target=_blank title="[new window]" href="">Safari resize fix</a></li>

    <li><a target=_blank title="[new window]" href="">Pens by Mike Foskett</a> &mdash; <a target=_blank title="[new window]" href="">webSemantics</a></li>


              /* Generic styling */
* {
  -moz-box-sizing: border-box;
  -webkit-box-sizing: border-box;
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
body {
  font-family: sans-serif;
  line-height: 1.5;
  background-color: #B5C6AF;
h1 {font-weight: 400}
.credits {margin: 2rem}
h2 {font-weight: 100}
ul {margin-left: 1rem}
li {margin: .5rem 0}
a {
  color: #000 !important;
  text-decoration: none;
  border-bottom: 1px solid currentColor;
  transition: all .3s ease-out;
  outline: 0 solid transparent;
a:focus {
  background-color: #fff;
  outline: .25em solid #fff;

.IMG {
  position: relative;
  /* Maintain image aspect-ratio */
  height: calc(100vw * 12 / 16);

[class^="IMG_title"] {
  position: absolute;
  z-index: 1;
  color: #fff;
  text-transform: uppercase;
  font-size: 1rem;
  /* Fluid-responsive font-size calculator: */
  /* 1em(16px) @ 20em(320px) increasing to 2em(32px) @ 40em(640px) */
  font-size: calc(1rem + ((1vw - 0.2em) * 5));
  /* WCAG: Shadow to increase contrast around text edges */
  text-shadow: 0 0 3px #000;

[class^="IMG_copy"] {
  position: absolute;
  white-space: nowrap;
.IMG_copy-1 {
  top: 20vw;
  left: 3.5vw;
  font-size: 1.125em;
.IMG_copy-2 {
  top: 41vw;
  left: 3.2vw;
  font-size: 1em;
.IMG_copy-3 {
  top: 12vw;
  left: 55.75vw;
  font-size: 1.125em;
.IMG_copy-4 {
  top: 28.75vw;
  left: 36.1vw;
  font-size: 0.75em;
  .IMG_copy-4 span{
    font-size: 2.65em;
    vertical-align: middle;
    display: inline-block;
    color: rgb(255,255,255);
    animation: color-rotate 4s infinite;
  @keyframes color-rotate {
    50% {color: #6d3; transform: scale(1.5)}
.IMG_copy-5 {
  top: 19.25vw;
  left: 73vw;
  font-size: 0.7em;
.IMG_copy-6 {
  top: 33vw;
  left: 71.4vw;
  font-size: 0.85em;
.IMG_copy-7 {
  top: 65vw;
  left: 34vw;
  .IMG_copy-7 span {
    display: inline-block;
    color: rgb(255,255,255);
    font-size: 1.5em;
    margin-right: .125em;
    vertical-align: baseline;
    animation: color-rotate-scale 2s infinite;
  @keyframes color-rotate-scale {
    50% {color: #6d3; transform: scale(1.5, 1)}

.IMG_bg {
  position: absolute;
  width: 100%;
  height: 100%;
  background-size: cover;
  /* Photo: Marcus Castro */
  background-image: url(;
              // Dirty 'orrible 'acky fix!
// Safari only - Fix for vw / vh units inside a Codepen iframe
(function () {
  var ua = navigator.userAgent.toLowerCase();
  if (ua.indexOf('safari') != -1) {
    if (!(ua.indexOf('chrome') > -1)) {

      // Safari only
      console.log("99 browsers but Safari's just one.");
      window.addEventListener("resize", function() {
      }, false);