body {
    background-color: #111;
    color: #fff;
    font-family: 'Segoe UI', sans-serif;
    display: flex;
    justify-content: center;
    align-items: flex-start;
    min-height: 100vh;
    margin: 0;
    padding: 40px 0;
    box-sizing: border-box;
}

.container {
    background-color: #1e1e1e;
    padding: 30px;
    border-radius: 12px;
    width: 90%;
    max-width: 500px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.5);
}

h1 {
    text-align: center;
    margin-bottom: 20px;
    color: #ffd700;
}

.task-input {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}

input[type="text"] {
    flex: 1;
    padding: 10px;
    border-radius: 5px;
    border: none;
    font-size: 16px;
}

button {
    padding: 10px 16px;
    border: none;
    border-radius: 5px;
    background-color: #FFD700;
    color: #000;
    font-weight: bold;
    cursor: pointer;
}

button:hover {
    background-color: #e6c200;
}

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

li {
    background-color: #2a2a2a;
    padding: 10px;
    margin-bottom: 10px;
    border-radius: 5px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

li.completed {
    text-decoration: line-through;
    opacity: 0.6;
}