This is a package to help you remove the accent from greek letters and capitalize them. Simply add the "make-capitals" class and you are all set.
npm i greek-caps-no-accent
<p class="make-capitals">Μου φάγανε το μουστοκούλουρο</p>
becomes
<p class="make-capitals">ΜΟΥ ΦΑΓΑΝΕ ΤΟ ΜΟΥΣΤΟΚΟΥΛΟΥΡΟ</p>