images not showing

Hello

I’m getting very confused this afternoon!

I have my main index php file (ie. homepage of site) and included in ‘blog content div’ the php stuff from theme index file i.e. get posts etc

I have edited all theme files, but when I click on individual post I’m not sure it is using theme php files, none of the images are showing. I have tried altering img src in these files to ‘http//:www…..etc etc and just /images…) I have also put in <base element> making base href=www.marble-design.co.uk

I just don’t know what to try next

any ideas for a confused person much appreciated

if it helps my site is https://www.marble-design.co.uk