body {
    font-family: Arial, sans-serif;
    background-color: #f5f5f5;
    margin: 0;
    padding: 20px;
}
.container {
    max-width: 400px;
    margin: auto;
    background: white;
    padding: 20px;
    border-radius: 4px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}
.new-task {
    display: flex;
    margin-bottom: 10px;
}
#task-input {
    flex: 1;
    padding: 8px;
}
#add-task {
    margin-left: 5px;
    padding: 8px 12px;
}
.completed {
    text-decoration: line-through;
    color: #888;
}
li {
    list-style: none;
    margin: 5px 0;
    display: flex;
    align-items: center;
}
li button {
    margin-left: auto;
}