body {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: #f7f9fc;
  margin: 0;
  padding: 0;
}

.container {
  max-width: 500px;
  margin: 50px auto;
  background: white;
  padding: 30px;
  border-radius: 8px;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

h1 {
  text-align: center;
  color: #333;
}

.todo-form {
  display: flex;
  margin-bottom: 20px;
}

.todo-form input {
  flex: 1;
  padding: 10px;
  border: 2px solid #ddd;
  border-radius: 4px;
}

.todo-form button {
  padding: 10px 20px;
  margin-left: 10px;
  border: none;
  background: #007bff;
  color: white;
  border-radius: 4px;
  cursor: pointer;
  transition: background 0.3s;
}

.todo-form button:hover {
  background: #0056b3;
}

.todo-list {
  list-style: none;
  padding: 0;
}

.todo-list li {
  display: flex;
  align-items: center;
  margin-bottom: 10px;
}

.todo-list span {
  flex: 1;
  margin-left: 10px;
}

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

.delete-btn {
  background: none;
  border: none;
  cursor: pointer;
  font-size: 18px;
}

input[type="checkbox"] {
  transform: scale(1.2);
  cursor: pointer;
}