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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-.

We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).

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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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HTML 

              
                <h1>JavaScript Playground</h1>   
<p>DOM Manipulation Practice</p>
<div id="listDiv">
  <p id="hiddenMsgSpan"></span>
  <ul id="list">
    <li>List item 1</li>
    <li>List item 2</li>
    <li>List item 3</li>
    <li>List item 4</li>
  </ul>
  <div id="addItemDiv">
    <input type="text" id="addItemInput">
    <button id="addItemButton">Add item</button>
  </div> <!--/.addItemDiv-->
  <button id="removeItemButton">Remove last item</button>
  <button id="toggleListButton">Hide list</button>
</div> <!--/.listDiv-->
<div id="footer">
  <p>Created by Nicole Archambault for independent JavaScript practice</p>
</div>

<script src="app.js"></script>
</body>
</html>
!

CSS 

              
                @import url('https://fonts.googleapis.com/css?family=Raleway:100,300');


$fonts: Raleway, sans serif;
$teal: #9fcdd8;
$purple: #8b7199;

body {
  font-family: $fonts;
  font-weight: 100;
  line-height: 1.5em;
}

h1 {
  color: $purple;
  font-weight: 300;
  + p {
    font-weight: bold;
  }
}

#hiddenMsgSpan {
  font-size: 0.85em;
  font-style: italic;
}

button {
  color: white;
  cursor: pointer;
  outline: none;
  background-color: $teal;
  border-radius: 5px;
  border-style: none;
  padding: 5px;
  margin-bottom: 0.35em;
}

.remove,
.down,
.up {
  padding: 6px;
}

.remove,
#removeItemButton {
  background: #b24747;
}

#removeItemButton {
  display: block;
  margin-top: 5px;
}

input {
  border-radius: 5px;
  border-style: none;
  border: 1px $teal solid;
  padding: 5px;
}

#list {
  padding-left: 0;
  list-style: none;
    & > li {
      display: flex;
      align-items: center;
      margin-bottom: 0.35em;
  }
    & > li button:first-child {
      margin-left: auto;
  }
    & > li > button + button {
      margin-left: 0.5em;
  }
}

#footer > p {
  font-size: 0.8em;
}
!

JS 

              
                const removeLi = document.querySelector(".remove");
const addItemInput = document.querySelector("#addItemInput");
const removeItemButton = document.querySelector("#removeItemButton");
const addItemButton = document.querySelector("#addItemButton");
const toggleListButton = document.querySelector("#toggleListButton");
const listDiv = document.querySelector("#listDiv");
const list = document.querySelector("#list");
const allLi = list.children;
const lastListItem = list.lastElementChild;
const firstListItem = list.firstElementChild;
const hiddenMsgDiv = document.querySelector("#hiddenMsgDiv");
const hiddenMsg = "List is currently hidden. Click below to show."

function attachListItemButtons(li) {
  let up = document.createElement("button");
    up.textContent = "Up";
    up.className = "up";
    if (li !== firstListItem) {
      li.appendChild(up);
    }
  let down = document.createElement("button");
    down.textContent = "Down";
    down.className = "down";
    if (li !== lastListItem) {
      li.appendChild(down);
    }
  let remove = document.createElement("button");
    remove.textContent = "Remove";
    remove.className = "remove";
    li.appendChild(remove);
}

function addNewItem() {
  let newItemName = addItemInput.value;
  let newItem = document.createElement("li");
  if (newItemName && event.target.id == "addItemButton" || event.which == 13 && newItemName) {
    newItem.textContent = newItemName;
    attachListItemButtons(newItem);
    list.appendChild(newItem);
    addItemInput.value = '';
  }
}

function removeItem(li) {
  if (event.target.className == "remove") {
    let targetLi = event.target.parentNode; //List item itself, including buttons
    list.removeChild(targetLi);
  } else {
    list.removeChild(li);
  }
}

// Check if li is the first or last child of ul
function isFirstLastLi(li) {
  if (li !== lastListItem) {
    document.querySelector(".down").style.display = "none";
  } else if (li !== firstListItem) {
      document.querySelector(".up").style.display = "none";
  } else {
      document.querySelector(".up").style.display = "inline-block";
      document.querySelector(".down").style.display = "inline-block";
    }
}

function moveItem() {
  let targetLi = event.target.parentNode; //list item itself, including buttons
  if (event.target.className == "up") {
    let prevLi = targetLi.previousElementSibling;
    if (prevLi) {
      isFirstLastLi(prevLi);
      list.insertBefore(targetLi, prevLi);
    }
  }
  if (event.target.className == "down") {
    let nextLi = targetLi.nextElementSibling;
    if (nextLi) {
      isFirstLastLi(nextLi);
      list.insertBefore(nextLi, targetLi);
    }
  }
}

function removeLastItem() {
  let lastItem = list.lastElementChild;
  list.removeChild(lastItem);
}

function toggleList() {
  if (list.style.display !== "none") {
    list.style.display = "none";
    hiddenMsgSpan.textContent = hiddenMsg;
    toggleListButton.textContent = "Show list";
  } else {
    hiddenMsgSpan.textContent = "";
    list.style.display = "block";
    toggleListButton.textContent = "Hide list";
}
}

// Attach buttons to all existing list items
for (i = 0; i < allLi.length; i++) {
  attachListItemButtons(allLi[i]);
}


/*--- EVENT LISTENERS ---*/
list.addEventListener("click", removeItem);
list.addEventListener("click", moveItem);
addItemButton.addEventListener("click", addNewItem);
addItemInput.addEventListener("keyup", addNewItem);
removeItemButton.addEventListener("click", removeLastItem);
toggleListButton.addEventListener("click", toggleList);
!
999px

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