* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: Arial, sans-serif;
  background-color: #f5f5f5;
  display: flex;
  justify-content: center;
  padding: 20px;
}

.container {
  width: 100%;
  max-width: 600px;
  background-color: white;
  border-radius: 8px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  padding: 20px;
}

h1 {
  text-align: center;
  margin-bottom: 20px;
  color: #333;
}

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

.form input {
  flex: 1;
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 4px 0 0 4px;
  font-size: 16px;
}

.form button {
  padding: 10px 15px;
  background-color: #4caf50;
  color: white;
  border: none;
  border-radius: 0 4px 4px 0;
  cursor: pointer;
  font-size: 16px;
}

.form button:hover {
  background-color: #45a049;
}

.todo-list {
  list-style-type: none;
}

.todo-item {
  display: flex;
  align-items: center;
  padding: 10px;
  border-bottom: 1px solid #eee;
}

.todo-item input[type="checkbox"] {
  margin-right: 10px;
}

.todo-item .text {
  flex: 1;
}

.todo-item.completed .text {
  text-decoration: line-through;
  color: #888;
}

.delete-btn {
  background-color: #f44336;
  color: white;
  border: none;
  border-radius: 4px;
  padding: 5px 10px;
  cursor: pointer;
  font-size: 14px;
}

.delete-btn:hover {
  background-color: #d32f2f;
}

.filters {
  display: flex;
  justify-content: center;
  margin-top: 20px;
}

.filter-btn {
  margin: 0 5px;
  padding: 5px 10px;
  background-color: transparent;
  border: 1px solid #ddd;
  border-radius: 4px;
  cursor: pointer;
}

.filter-btn.active {
  background-color: #4caf50;
  color: white;
  border-color: #4caf50;
}