* {
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', Arial, sans-serif;
  background: #f2f4f8;
  display: flex;
  justify-content: center;
  padding: 40px 16px;
  margin: 0;
  color: #222;
}

.container {
  background: #fff;
  width: 100%;
  max-width: 480px;
  padding: 24px 28px;
  border-radius: 10px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
}

h1 {
  text-align: center;
  margin-top: 0;
  font-size: 1.6rem;
}

#todo-form {
  display: flex;
  gap: 8px;
  margin-bottom: 20px;
}

#todo-input {
  flex: 1;
  padding: 10px 12px;
  border: 1px solid #ccc;
  border-radius: 6px;
  font-size: 1rem;
}

button {
  padding: 10px 16px;
  border: none;
  border-radius: 6px;
  background: #4a6cf7;
  color: #fff;
  font-size: 1rem;
  cursor: pointer;
}

button:hover {
  background: #3a58d9;
}

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

#todo-list li {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 0;
  border-bottom: 1px solid #eee;
}

#todo-list li:last-child {
  border-bottom: none;
}

#todo-list li span {
  flex: 1;
  word-break: break-word;
}

#todo-list li.completed span {
  text-decoration: line-through;
  color: #999;
}

.delete-btn {
  background: #e74c3c;
  padding: 6px 10px;
  font-size: 0.85rem;
}

.delete-btn:hover {
  background: #c0392b;
}

.empty-message {
  text-align: center;
  color: #888;
}