How to change the border colour of the Row Numbers and Column Names in Calc?

[tukykarmakar]

Hello all, hope you’re well. I recently installed LibreOffice and was customizing it to suit my needs. This is the first time I’m using LibreOffice.

I installed the Dark Gray theme from the Extension portal and then I edited the theme to make it darker. I customized the colours from Customization section in Tools > Options > LibreOffice > Appearance. However, I’m not aware which of the Customization Items corresponds to the colour of these borders that I marked in the screenshot.

Which option under the Items menu would change the colour of these borders?

[Zizi64]

Do you mean the background color of the column header (A, B, C…) and the row header (1, 2, 3…)?

Or do you mean the grid lines (“border”) color of these row and column headers?