A simple JS script toggles new styles which applies 'background-color' in light colours and a dashed red outline properties into the selected elements.

JS Code example

document.getElementById('inspector').addEventListener('click', function () {
document.body.classList.toggle('inspectorActive');
});

CSS usage:

/* debug inspector */
.inspectorActive .container {
background-color: lightcoral !important;
outline: 2px dashed red !important;
}