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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.

   The following is a common layout you would see in an email client.

   When a user clicks a checkbox, holds Shift, and then clicks another checkbox a few rows down, all the checkboxes inbetween those two checkboxes should be checked.
  <div class="inbox">
    <div class="item">
      <input type="checkbox">
      <p>This is an inbox layout.</p>
    <div class="item">
      <input type="checkbox">
      <p>Check one item</p>
    <div class="item">
      <input type="checkbox">
      <p>Hold down your Shift key</p>
    <div class="item">
      <input type="checkbox">
      <p>Check a lower item</p>
    <div class="item">
      <input type="checkbox">
      <p>Everything inbetween should also be set to checked</p>
    <div class="item">
      <input type="checkbox">
      <p>Try do it with out any libraries</p>
    <div class="item">
      <input type="checkbox">
      <p>Just regular JavaScript</p>
    <div class="item">
      <input type="checkbox">
      <p>Good Luck!</p>
    <div class="item">
      <input type="checkbox">
      <p>Don't forget to tweet your result!</p>

  <p class="details">Here is a <a href="http://wes.io/f1oa" target="_blank">video</a> on how it should work. I'll post my answer after everyone has had a chance to do it.</p>

                  html {
      font-family: sans-serif;

    .inbox {
      margin:50px auto;
      box-shadow:10px 10px 0 rgba(0,0,0,0.1);
    .item {
      border-bottom: 1px solid #F1F1F1;

    .item:last-child {

    input:checked + p {
      text-decoration: line-through;

    input[type="checkbox"] {
    p {
      transition:background 0.2s;
      font-family:'helvetica neue';
      font-size: 20px;
      font-weight: 200;
      border-left: 1px solid #D1E2FF;
    .details {
      text-align: center;
      font-size: 15px;

        This is the answer. 

        If you haven't yet tried this challenge, delete everything here
        don't peek!
        Give it a shot yourself first.
        Then come look.

    // First we create an array of all the checkboxes - we will use this twice in our app
    // we use slice.call to convert the node list to a real array
    var checkboxes = [].slice.call(document.querySelectorAll('.inbox [type="checkbox"]'));
    // we create a variable called lastChecked that will hold a reference to the last checkbox we checked. This will let us figure out which way to go 
    var lastChecked;

    // create the handler that will run when someone "clicks" a box
    function handleCheck(e) {

      // check if 1) they are holding shift 2) we checked this box (it's not an un-check)
      if(e.shiftKey && this.checked) {
        // create a flag boolean - more on this in a sec
        var inBetween = false;

        // loop through each input
        checkboxes.forEach( input => {

          // Here is where we make our sausage.
          // We want to see if the current loop iteration is 
          // either input we checked, or the last one we checked
          // This will allow us to turn on the checking (inBetween) when we pass one of them, and turn it off when we pass the other. 
          // This might be a little confusing but it allows us to go both ways
          if(input === this || input === lastChecked) {
            inBetween = !inBetween;
          // finally, if we are currently inBetween the lastChecked and the one that
          // was just checked. Go ahead and mark that one as checked
          if(inBetween) {
            input.checked = true;
      // update last Checked regardless
      lastChecked = this;

    // loop over each checkbox and attach the event listener to it
    checkboxes.forEach(checkbox => checkbox.addEventListener('click',handleCheck));

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