Background Image stretching

hello

I am usingVersion 1.2.5.2

I don’t want my background to stretch but I am not able to find a way of stopping it.

I have made my background the correct size to sit top centre but if I stretch my browser out or view on a larger monitor the background stretches to stay level to the sides of the screen meaning the centre gets larger.

Please see my development site at http://oxfordshireguardiandev.apps-1and1.net/

Thank you.

https://wordpress.org/plugins/background-manager/