style.css

body {
  font-family: Helvetica, Arial, sans-serif;
  font-size: 18px;
}

.container {
  margin: 20px auto;
  width: 500px;
  border: 1px solid #e6e6e6;
  border-radius: 3px;
}

h1 {
  text-align: center;
}

form {
  padding: 0 0 20px;
}

input#new-todo {
  display: block;
  width: 478px;
  border-radius: 3px;
  border: 1px solid #e6e6e6;
  padding: 10px;
  font-size: 18px;
}

ul#todolist {
  list-style: none;
  margin: 0;
  padding: 0;
}

ul#todolist li {
  padding: 5px;
  border: 1px solid #e6e6e6;
  border-radius: 3px;
}

ul#todolist li:hover {
  background-color: #e6e6e6;
}

ul#todolist .todo.completed label {
  text-decoration: line-through;
  color: #999;
}

.footer {
  margin-top: 10px;
  background: #323232;
  color: #e6e6e6;
  padding: 5px;
  border-bottom-left-radius: 3px;
  border-bottom-right-radius: 3px;
}

.footer a:link,
.footer a:hover,
.footer a:visited {
  color: #e6e6e6;
  text-decoration: none;
}

.footer a:hover {
  text-decoration: underline;
}