Customising syles

Hi there,
I’ve got this page running. Originally I had the images opening in a lightbox, but because of the z-index settings of my menu, it displayed strangely (the menu was showing up over the top of the image in lightbox). I changed it so that now the image opens up in a different page (well, it keeps my page content, but the url changes to e.g. https://gemm-int.com/mother-of-pearl-panels-test/nggallery/image/siminetti-3d-golden-cube and only shows the one image rather than the gallery). Seems a bit strange that there’s no link back to the main selection of images. Also, if I try to change some of the styles on here to match in with my theme, it seems to override all style settings. E.g. if I add .counter {color: #8d612a;}, it changes the colour of the text as I want it to … but it removes all the style from that whole section, making the image larger, and everything aligned to the left (and the back – forward buttons get messed up). Am I missing something here? Surely it shouldn’t be so hard to make small customisations?
Many thanks
Nikki

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