This is completely random but please help if you can.
When I was a young teenager (so mid 1990s) I had a set of three books that were unrelated stories but the same series if that makes sense.
I loved them and re read them lots but I cannot for the life of me remember who wrote them or the names of them.
Here is where it gets fun! All I can remember is a minor plot line from one of them about it being set in Scotland, and the girl in the story discovered some sort of secret nuclear bunker in a cave or something? I think the books I had were hard backed and there was a blue one, a green one and a pink one. They had total famous five vibes (slightly more modern than famous five but definitely set in 1980s or 1990s)
If anyone has any idea what I am talking about please help me to stop thinking I've imagined this!