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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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Adding Classes

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About the <head>

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Insecure Resource

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CSS

About CSS Preprocessors

CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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Packages

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Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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HTML 

              
                <section>
  <ul id="parent-ul-1">
    <li id="li-1" class="my-class">Item 1</li>
    <li id="li-2" class="my-class">Item 2</li>
    <li id="li-3" class="my-class">Item 3</li>
  </ul>
  <p id="display-msg-1"><p>
</section>

<section>
  <ul id="parent-ul-2">
    <li id="li-4" class="my-class">Item 4</li>
    <li id="li-5" class="my-class">Item 5</li>
    <li id="li-6" class="my-class">Item 6</li>
  </ul>
  <p id="display-msg-2"><p>
</section>

<section>
  <ul id="parent-ul-3">
    <li id="li-7" class="my-class">Item 7</li>
    <li id="li-8" class="my-class">Item 8</li>
    <li id="li-9" class="my-class">Item 9</li>
  </ul>
  <p id="display-msg-3"><p>
</section>

<section>
  <button id="unbind" type="button">Unbind Column 3</button>
  <button id="bind" type="button">Bind Column 3</button>
  <p id="display-msg-4"><p>
</section>
!

CSS 

              
                $pri: #888;
$pri-light: lighten($pri, 20%);
$pri-dark: darken($pri, 20%);
$pri-dark-x: darken($pri, 30%);
* { box-sizing: border-box; }
body {
  font-family: arial;
  margin: 2em 1em;
  background: #222;
}
@keyframes play {
   0% { left: 0; }
   50% { left: 20px; }
   100% { left: 0;}
}
.moveMe {
  animation: play .8s;
  position: relative;
  margin: 0;
}
section {
  width: 25%;
  float: left;
  padding-right: 1%;
  }
ul {
  width: 100%;
  color: $pri-light;
  li {
    background-color: $pri-dark-x;
    border-bottom: 2px solid $pri-light;
    padding: 1em;
    list-style-type: none;
    cursor: pointer;
  }
 }
p {
  padding: 1em 0 0 0;
  color: #fff;
  font-size: 1em;
}
button {
  width: 100%;
  display: block;
  border: 0;
  background-color: $pri-dark;
  padding: .5em 1em;
  margin-bottom: 1em;
  font-size: 1em;
  color: $pri-light;
  border: 5px solid  $pri-light;
  &:hover { background-color: $pri-dark-x; }
  &:active { 
    box-shadow: inset 0 0 5px $pri-dark-x;
    background-color: $pri-dark-x; }
  &:focus { outline: 0; }
}
!

JS 

              
                
// Event delegation is useful in that you only place the event listener on the parent to capture the bubbled event - imagine a table of 1000 rows. The callback function lets you handle it in any way.

var dm1 = document.getElementById("display-msg-1");
document.getElementById("parent-ul-1").addEventListener("click", function(e) {
  if(e.target) {
    var msg = "Clicked on: " + e.target.firstChild.nodeValue;
    // You could capture any attribute of this clicked element
    // "ID:" + e.target.id or "Class:" + e.target.className
    addRemoveClass(dm1, msg);
  }
});
function addRemoveClass(c, msg) {
  c.innerHTML = msg;
  c.classList.remove("moveMe");
  c.offsetWidth = c.offsetWidth;
  c.classList.add("moveMe");
}
// And with jQuery .delegate
$("#parent-ul-2").delegate( "li", "click", function() {
  var dm2 = $("#display-msg-2");
  var msg = dm2.text( "Clicked on: " + $(this).text());
  jq_addRemoveClass(dm2, msg);
});
// For .on just reverse the event and target
$("#parent-ul-3").on("click", "li", function() {
  var dm3 = $("#display-msg-3");
  var msg = dm3.text( "Clicked on: " + $(this).text());
  jq_addRemoveClass(dm3, msg);
});
function jq_addRemoveClass(c, msg) {
  c.removeClass("moveMe");
  c.outerWidth(true);
  c.addClass("moveMe");
}
// .off - removes both .delegate and .on
$( "#unbind" ).click(function() {
  $( "#parent-ul-3" )
    .off( "click", "li")
    .find( "#display-msg-4" )
    $("#display-msg-4" ).text("Removed .on from C3");
});
$("#bind").click(function() {
  // Real world, I'd abstract the sect 3 declaration into it's own function
    $("#parent-ul-3").on("click", "li", function() {
      
      var dm3 = $("#display-msg-3");
      var msg = dm3.text( "Clicked on: " + $(this).text());
      jq_addRemoveClass(dm3, msg);
    });
  $("#display-msg-4").text("Added .on to C3");
})
!
999px

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