style.css

* {
  box-sizing: border-box;
}

body {
  margin: 0px;
  font-family: 'Oswald', Helvetica, sans-serif;
  justify-content: center;
}

div {
  width: 100%;
  display: flex;
  justify-content: center;
}

.title {
  text-align: center;
  font-size: 40px;
  color: #eee;
  letter-spacing: 4px;
  background-color: #04CC39;
  padding: 20px;
  margin: 0px;
}

p {
  text-align: center;
}

input {
  padding: 2px 5px;
}

button {
  background-color: #FF9C3B;
  border: none;
  color: #fff;
  font-weight: bold;
  text-align: center;
  text-decoration: none;
  display: inline-block;
  padding: 7px 20px;
  margin-left: 10px;
  cursor: pointer;  
  box-shadow: 0 2px 4px 0 rgba(0,0,0,0.5);
}

button:hover {
  background-color: #FF8105;
  box-shadow: 0 5px 8px 0 rgba(0,0,0,0.5);
}

ul {
  list-style-type: none;
  padding: 0px;
}

li {
  font-weight: bold;
  line-height: 1.5em;
  background-color: #33DB5F;
  padding: 10px 15px;
  margin: 2px;
}

li > button {
  float: right;
}

.done {
  text-decoration: line-through;
}