body {
    font-family: sans-serif;
    margin: 0;
    padding: 20px;
}

header {
    text-align: center;
}

#username, #fetch-button {
    width: 100%;
    padding: 10px;
    margin-bottom: 10px;
    border: 1px solid #ccc;
    border-radius: 5px;
}

#repositories {
    margin-top: 20px;
}