I would want to set the back ground color of a cell based on the binded Burshdata, but it does not fill the whole cell.

The image demostrating my problem

Here is my code:

                        <GridViewColumn>
                            <GridViewColumn.CellTemplate>
                                <DataTemplate>
                                    <TextBlock Text="{Binding Name}" HorizontalAlignment="Stretch"
                                               Foreground="{Binding FontColor}"
                                               Background="{Binding BackGroundColor}"/>
                                </DataTemplate>
                            </GridViewColumn.CellTemplate>
                            <GridViewColumn.Header>Csapatnév</GridViewColumn.Header>
                        </GridViewColumn>