There is nothing that can be done about the template I'm afraid, because it's a default PHPBB template, made by them and the only would be install other templates for users to switch between and currently there isn't.
Alternatively the alternative option would be to alter the colour / brightness / contrast settings on your monitor, or if you have windows control panel type software on your PC or mac, for adjusting the gamma; try altering the RBG or the hue, luminocity and / or saturation, which might help.
You can change the text colour of things you post if that helps at all, but I'm thinking it probably wouldn't.
I really hope this does not spoil your enjoyment of using the forums, because I know you of old and I know what a wonderful and charming person you are with very heartfelt expressive and beautiful things to say and any member of your calibre that could be hindered from posting again, would make me feel a little sad for you, because I think you're such a wonderful person

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The old template was subsilver in PHPBB 2, but that to knowledge was discontinued and this one the prosilver is a default.
It seems like you are able to post in some way, but the suggestions I gave you and the other option of using high contrast via windows accessibility options, which I have on XP but obviously depends on your operating system, are all I can say at this moment in time.
I don't have control over the PHP code on this forum, just features. Any change to coding would have to be done via the programmers, at cost to the other admin, as he doesn't deal with any actually PHPBB / template coding changes.
I wish I could do more to help you, as it's frustrating for me too, but I can only make suggestion I think might help in some way and try best for you Amber, as I want every good member of this site, no matter who they are to able to have a rewarding user experience, because as I am sure you will remember, people like you never stop mattering to me and I want people feel comfortable and happy as much as possible when they post and interact with others.
Maybe one or more things I have suggested might work, but due to limitations regards coding and regards what PHPBB have inbuilt as default settings for the forums, the suggestion given are all I can really offer.
I really hope you can find a way to post, because you were always a fantastic member to have around and I never failed ot be touched by your incredibly beautiful accounts of your difficult life and I hope Shapefit will still be able to provide you with an outlet for your heart, stories and personality, because I for one would be absolutely delighted to have your words and support for others around here again.
Take care and best wishes

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