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<div class="header">
  <h2 >待辦清單</h2>
  <input type="text" id="todo-input" placeholder="待辦事項">
  <button onclick="addTodo()" class="addBtn">新增</button>

<ul id="todo-list">
  <li class="checked">先完成這個</li>


                /* Remove margins and padding from the list */
ul {
    margin: 0;
    padding: 0;

/* Style the list items */
ul li {
    cursor: pointer;
    position: relative;
    padding: 12px 8px 12px 40px;
    background: #eee;
    font-size: 18px;
    transition: 0.2s;

    /* make the list items unselectable */
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;

/* Darker background-color on hover */
ul li:hover {
    background: #ddd;

/* When clicked on, add a background color and strike out text */
ul li.checked {
    background: #888;
    color: #fff;
    text-decoration: line-through;

/* Add a "checked" mark when clicked on */
ul li.checked::before {
    content: '';
    position: absolute;
    border-color: #fff;
    border-style: solid;
    border-width: 0 2px 2px 0;
    top: 10px;
    left: 16px;
    transform: rotate(45deg);
    height: 15px;
    width: 7px;

/* Style the close button */
.close {
    position: absolute;
    right: 0;
    top: 0;
    padding: 12px 16px 12px 16px;

.close:hover {
    background-color: #f44336;
    color: white;


                var myNodelist = document.getElementsByTagName("li");
var i;
for (i = 0; i < myNodelist.length; i++) {
  var span = document.createElement("SPAN");
  span.className = "close";

  span.innerHTML = 'x';

// Click on a close button to hide the current list item
var close = document.getElementsByClassName("close");
var i;
for (i = 0; i < close.length; i++) {
  close[i].onclick = function() {
    var div = this.parentElement; = "none";

// Add a "checked" symbol when clicking on a list item
var list = document.querySelector('ul');
list.addEventListener('click', function(ev) {
  if ( === 'LI') {'checked');
}, false);

var myInput = document.getElementById("todo-input");
// Create a new list item when clicking on the "Add" button
function addTodo() {
  var li = document.createElement("li");
  var inputValue = document.getElementById("todo-input").value;
  var t = document.createTextNode(inputValue);
  if (inputValue === '') {
  } else {
  myInput.value = "";

  var span = document.createElement("SPAN");
  var txt = document.createTextNode("x");
  span.className = "close";

  for (i = 0; i < close.length; i++) {
    close[i].onclick = function() {
      var div = this.parentElement; = "none";