html.css-debug * {
    outline: 1px solid crimson;
}

html.css-debug div {
    outline: 1px solid orange;
}

html.css-debug article,
html.css-debug section {
    outline: 1px solid lime;
}

html.css-debug a {
    outline: 1px solid mediumslateblue;
}

html.css-debug a:hover {
    background-color: mediumslateblue;
    opacity: 0.9;
}

html.css-debug a.btn,
html.css-debug button {
    outline: 1px solid seagreen;
    background-color: lightseagreen;
}