body {
  font-family: Arial, sans-serif;
  background: #f4f4f4;
}

.container {
  max-width: 400px;
  margin: 50px auto;
  background: #fff;
  padding: 20px;
  border-radius: 6px;
}

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

li {
  display: flex;
  justify-content: space-between;
  margin: 8px 0;
}

.completed {
  text-decoration: line-through;
  color: gray;
}