bitwarden-estensione-browser/src/connectors/duo.scss

html, body {
    margin: 0;
    padding: 0;
}

body {
    background: #efeff4 url('../images/loading.svg') 0 0 no-repeat;
}

iframe {
    display: block;
    width: 100%;
    height: 400px;
    border: none;
    margin: 0;
    padding: 0;
}