Change the background colour of the footer row cell

I am failing to change the background color of a cell in the footer row in a column with an aggregate functionI’m trying this, but it’s not working. Could someone help me

if ($this->RowType == ROWTYPE_AGGREGATE) { 
    $this->name->CellAttrs["class"] = "";
    $this->name->CellAttrs["style"] = "background-color: #ff3333"; 
}

Thanks for any help

You may read Inspect HTML element and add your own CSS styles and check why your style is not effective.