I would like to create a pop-up when I press "details". I don't know how to deal with "createElement".
let ul = document.createElement('ul');
let detail = document.createElement('details');
detail.appendChild(ul); // element du detail
let summary = document.createElement('div');
summary.appendChild(detail);
let colDetail = document.createElement('td');
colDetail.className = 'td-detail';
colDetail.appendChild(summary);<th>Détails</th>You can look into jquery popup overylay plugin.
https://dev.vast.com/jquery-popup-overlay/
The instructions on how to make an overlay popup are great.
You can use .addEventListener() or .onClick methods on element.
A popup in the page is called a modal. The easiest way to do it is not to create the new element, but rather have it all along with a CSS-class that is hidden:
.nodisplay {
display: none
}
Then you hide or show it removing the class with
element.classList.add('nodisplay')
or
element.classList.remove('nodisplay')