in src/frontend/www/js/main.js [166:179]
function checkHandler(e){
let complete = e.target.checked;
let title = e.target.parentElement.childNodes[1].innerHTML;
let id = e.target.parentElement.childNodes[1].id.split("-")[1];
if (complete){
e.target.parentElement.parentElement.classList.add("complete");
} else{
e.target.parentElement.parentElement.classList.remove("complete");
}
updateTodo(id, title, complete);
}