body {
  background: linear-gradient(135deg, #e0f7fa, #fff3e0);
  font-family: 'Segoe UI', sans-serif;
  display: flex;
  justify-content: center;
  align-items: flex-start;
  height: 100vh;
  padding-top: 60px;
  margin: 0;
}

.todo-container {
  background-color: white;
  padding: 30px;
  border-radius: 15px;
  box-shadow: 0 5px 15px rgba(0,0,0,0.15);
  width: 90%;
  max-width: 400px;
  text-align: center;
}

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

.input-section {
  display: flex;
  justify-content: space-between;
  margin-bottom: 20px;
}

#todo-input {
  flex: 1;
  padding: 10px;
  border-radius: 10px;
  border: 1px solid #ccc;
  margin-right: 10px;
  font-size: 16px;
}

#add-btn {
  padding: 10px 15px;
  border: none;
  border-radius: 10px;
  background-color: #00bfa5;
  color: white;
  font-weight: bold;
  cursor: pointer;
  transition: 0.3s;
}

#add-btn:hover {
  background-color: #00897b;
}

#todo-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.todo-item {
  background: #f1f8e9;
  padding: 12px 15px;
  border-radius: 10px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 10px;
  transition: 0.3s;
}

.todo-item.completed {
  text-decoration: line-through;
  opacity: 0.6;
  background: #e0e0e0;
}

.todo-buttons {
  display: flex;
  gap: 10px;
}

.todo-buttons button {
  border: none;
  background: none;
  cursor: pointer;
  font-size: 18px;
}