body {
  font-family: sans-serif;
  background: #f0f0f0;
  display: flex;
  justify-content: center;
  padding: 50px;
}

.app {
  background: white;
  padding: 20px;
  border-radius: 8px;
  width: 300px;
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

form {
  display: flex;
  gap: 10px;
}

input[type="text"] {
  flex: 1;
  padding: 8px;
}

button {
  padding: 8px;
  cursor: pointer;
}

ul {
  list-style: none;
  padding-left: 0;
  margin-top: 20px;
}

li {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
}

.completed {
  text-decoration: line-through;
  color: gray;
  opacity: 0.6;
}
.todo-checkbox {
  width: 18px;
  height: 18px;
}

.todo-label {
  flex: 1;
}

.delete-btn {
  background: #ff4d4d;
  color: white;
  border: none;
  border-radius: 4px;
  padding: 4px 8px;
  cursor: pointer;
  margin-left: 8px;
}