body {
    font-family: -apple-system, Arial, sans-serif;
    max-width: 600px;
    margin: 40px auto;
    padding: 0 20px;
    background: #f4f4f9;
    color: #333;
}

h1 {
    text-align: center;
    color: #4a4a8a;
}

form {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}

input[type="text"] {
    flex: 1;
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 6px;
    font-size: 16px;
}

button {
    padding: 10px 16px;
    background: #4a4a8a;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 16px;
}

button:hover {
    background: #38386b;
}

ul {
    list-style: none;
    padding: 0;
}

li {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: white;
    padding: 12px 16px;
    margin-bottom: 8px;
    border-radius: 6px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

li a {
    text-decoration: none;
    font-size: 18px;
}

.done {
    text-decoration: line-through;
    color: #aaa;
}