body {
  font-family: sans-serif;
  background: #f4f6f9;
  margin: 0;
  padding: 0;
}
header {
  background: #0d6efd;
  color: white;
  padding: 16px;
  text-align: center;
}
.card {
  display: flex;
  gap: 8px;
  padding: 12px;
}
#todoInput {
  flex: 1;
  padding: 10px;
  border-radius: 8px;
  border: 1px solid #ccc;
}
button {
  padding: 10px 14px;
  border: none;
  border-radius: 8px;
  background: #0d6efd;
  color: white;
  cursor: pointer;
}
.list {
  list-style: none;
  padding: 0;
  margin: 20px;
}
.list li {
  background: white;
  border: 1px solid #ddd;
  border-radius: 8px;
  padding: 10px;
  margin-bottom: 8px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.list li.done {
  text-decoration: line-through;
  color: gray;
}