Greetings, I do not understand what problem there is in the route to access the css file and give styles to my jsp. will they know if I'm jumping something? It does not make sense to keep working on the project if I do not solve this first. This is the first time that I try to use css in a jsp file, so I do not know if this process is different from how it is done in HTML or in Java.
Add type .
<link rel="stylesheet" type="text/css" href="CSS/Estilos.css"/>
Have you tried to set absolute routes?
< link rel="stylesheet" type="text/css" href="/tuaplicacion/CSS/estilos.css"/>
Have one thing in mind, for all the pages the path "css / estilos.css" is not the same, because it depends on the hierarchy of pages and folders you have, the css for them will be in one place or another .
The best way is to use a full path instead of a relative one, I would use something like link and add it to it as a total and not relative route.
thanks to all for the help, at the end the route was simple CSS / Estilos.css only that I had a problem of names with the classes of the css (UPS) and only thought that the error should be something different since I had never used CSS in jsp, I focused from the beginning on the error that came from some configuration or that I had to move it from folder.