I have a created a HTML table which is editable.
The table contains some cells are predefined with the numbers 1-5, than there is section where the user can enter data and in the last column there should be the result of the data of the previous cells. Now I want the add a formula like you have for instances with Excel. How I can make calculations in the HTML table with Javascript or any other method?

I’ve created this dummy table based on my real project. The issue I’m having is that the border on the Table Header is moving when the content of the cells changing (no-wrap) hence the border overlapped by the bg color of the cell (my understanding)