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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.

    line-height lock<br>
    1.4 ➡ 1.8

<p class="standard"><em>The line-height of the paragraphs goes from 140% to 180% between two breakpoints (20em and 60em, i.e. 320px and 960px with default settings). The smaller gray numbers are the actual line-height as a ratio, computed with JS.</em></p>

<p class="bigger">Bigger text — Lorem ipsum dolor sit amet, consectetur adipisicing elit. Aut consequuntur distinctio enim iure nesciunt officia quia saepe veritatis? Ab aliquid dolor iste mollitia provident soluta voluptas? Distinctio dolore tempore tenetur!</p>

<p class="standard">Ab aliquam at blanditiis cum delectus eaque ex fuga, fugit hic, illo impedit laborum natus nesciunt nisi nostrum placeat ratione rerum sequi similique sit? A corporis debitis delectus deserunt ea eos harum libero maiores necessitatibus nemo nobis odio omnis, placeat quasi, rerum sunt voluptatem! Dignissimos enim, facilis illo itaque nemo tempore. Adipisci, eos, illum.</p>
              /* CSS locks */
p {
  line-height: 1.4;
.bigger {
  font-size: 166%;
@media (min-width: 20em) {
  .standard {
    line-height: calc( 140% + .4 * (100vw - 20rem) / (60 - 20) );
  .bigger {
    line-height: calc( 140% + .4 * 1.66 * (100vw - 20rem) / (60 - 20) );
@media (min-width: 60em) {
  .bigger {
    line-height: 1.8;

/* Show the computed line-height (as a ratio) */
[data-lh]::before {
  content: attr(data-lh);
  display: inline-block;
  vertical-align: 15%;
  padding: 2px 4px 3px;
  border-radius: 3px;
  margin-right: 5px;
  font-size: 14px;
  line-height: 1;
  color: #fff;
  background-color: #777;

/* Cosmetic styles */
body {
  font-family: Helvetica Neue, Arial, sans-serif;
  max-width: 720px;
  margin: 60px auto;
  padding: 0 20px;
  /* Just for fun, let’s size the main column relative to vw too */
  width: calc( 100px + 50vw );
h1 {
  margin: 1.25em 0;
  font-size: 300%;
  line-height: 1.2;
              var paragraphs = document.querySelectorAll('p');
function updateInfo() {, function (p) {
        var styles = getComputedStyle(p);
        var lh = parseFloat(styles.lineHeight.replace('px', ''));
        var fs = parseFloat(styles.fontSize.replace('px', ''));
        var ratio = Math.round((lh / fs) * 100) / 100;
        p.setAttribute('data-lh', '' + ratio);
window.addEventListener('resize', updateInfo);
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