* {
  box-sizing: border-box;
}

body {
  font-family: 'Arial', sans-serif;
  background-color: #f2f2f2;
  margin: 0;
  padding: 10px;
}

.container {
  max-width: 600px;
  margin: auto;
  background-color: #fff;
  padding: 20px;
  border-radius: 16px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}

h1 {
  font-size: 1.8rem;
  text-align: center;
  color: #333;
  margin-bottom: 20px;
}

form {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

input[type="text"] {
  flex: 1;
  padding: 12px;
  font-size: 1rem;
  border: 1px solid #ccc;
  border-radius: 8px;
}

button {
  padding: 12px 18px;
  font-size: 1rem;
  background-color: #0077cc;
  color: #fff;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  flex-shrink: 0;
}

button:hover {
  background-color: #005fa3;
}

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

li {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: #f0f0f0;
  padding: 12px;
  margin-bottom: 10px;
  border-radius: 8px;
  font-size: 1rem;
}

li button {
  background: #ff4d4d;
  border: none;
  color: white;
  font-size: 1.1rem;
  padding: 6px 10px;
  border-radius: 50%;
  cursor: pointer;
}

.completed {
  background-color: #d4edda;
  text-decoration: line-through;
}
.editable {
  padding: 2px 4px;
  background-color: #fff8dc;
  border-radius: 4px;
}