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Use npm Packages

We can make npm packages available for you to use in your JavaScript. We use webpack to prepare them and make them available to import. We'll also process your JavaScript with Babel.

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HTML Settings

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.

  <input id="example-input-1" type="text" name="Name">
  <div class="flex-container">
    <div class="flex-spacer"></div>
    <label for="example-input-1">Type Something!</label>
              body * {
  box-sizing: border-box;
  font-family: sans-serif;
  font-size: 16px;

form {
  position: relative;
  width: 100%;

.flex-container {
  line-height: 20px;
  border-radius: 3px;
  transition: all .4s ease-out;

input {
/*set z-index of input higher than that of label so hover states and clicks get registered on input element*/
  z-index: 1;
  position: relative;
  width: 100%;
  padding: 20px;
/*transparent background allows label text to be seen, even though input is on top of label*/
  background-color: transparent;
  border: 2px solid black;

input:focus {
  outline: none;

.flex-container {
  display: flex;
  flex-flow: row nowrap;
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;

label {
  flex-grow: 0;
  position: relative;
  border-radius: inherit;
  transition: inherit;

.flex-spacer {
  background-color: #DDD;

label {
  color: #777;
/*padding of input + border of input*/
  padding: 22px;

/*class="not-empty" added to input elements when text is added to the input field*/
input.not-empty {
    border-color: #F75;

input.not-empty + .flex-container .flex-spacer {
  flex-grow: 1;

input.not-empty + .flex-container label {
/*set z-index of label higher than that of input so text gets hidden behind label*/
  z-index: 2;
  color: #FFF;
  background-color: #F75;
              function handleInput() {
  if (this.value != "") {
  } else {

var field = document.querySelector("input");

field.addEventListener("input", handleInput);
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