* {
  box-sizing: border-box;
  font-family: Arial, sans-serif;
}

body {
  height: 100vh;
  margin: 0;
  display: flex;
  justify-content: center;
  align-items: center;
  background: linear-gradient(135deg, #4facfe, #9b59b6);
}

.todo-box {
  background: white;
  width: 350px;
  padding: 25px;
  border-radius: 15px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

.todo-box h1 {
  text-align: center;
  margin-bottom: 20px;
}

.input-area {
  display: flex;
  gap: 10px;
}

.input-area input {
  flex: 1;
  padding: 10px;
  border-radius: 8px;
  border: 1px solid #ccc;
}

.input-area button {
  padding: 10px 15px;
  border: none;
  background: #6c5ce7;
  color: white;
  border-radius: 8px;
  cursor: pointer;
}

.input-area button:hover {
  background: #5a4bdc;
}

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

li {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px;
  margin-bottom: 10px;
  background: #f5f5f5;
  border-radius: 8px;
}

.todo-left {
  display: flex;
  align-items: center;
  gap: 10px;
}

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

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