remove background-image

Hello,
I’d like to remove the background image from one or two pages. I tried adding this custom css: body.custom-background { background-image: none; } to the Custom CSS on one page in my website: http://curlytail.cabowebsolutions.com/photos-photos-more-photos/

But it did not remove the background image. I see my custom CSS when I inspect the page. The default CSS seems to be overwriting it.

body.custom-background {
background-image: url(http://curlytail.cabowebsolutions.com/wp-content/uploads/2017/04/2017-04-19-10.00.01.jpg);
background-position: left top;
background-size: cover;
background-repeat: no-repeat;
background-attachment: fixed;
}
(index):64
body.custom-background {
background-image: none;
}

The lines in index 64 have strike-through.
What am I doing wrong?
Thanks in advance!