pmwiki and https

Hello,

My pmwiki site is pretty ancient, but I like it :-).

I just (some weeks ago at least) noticed that at first glance it appears 
not well

after some interrogations it seems linked to https. As far as I know my 
server is https compatible. I use the standard pmwiki responsive skin

https://www.pmwiki.org/wiki/Skins/PmWiki-responsive

these may not be in the very last version, but mot too old neither

https://dodin.org/index.php?n=Main.HomePage

is there something I have to check? My browsers have my site on cache so 
testing is pretty hard :-(

thanks
jdd