See the screenshot below! Not sure if the reading team is aware of this issue or if it affects other wikis. Please let me know asap if we should fix this within the Spanish Wikipedia community or if we should wait for the general fix promised some weeks ago. Cheers!
Topic on Talk:Reading/Web/Projects/Mobile Page Issues/Flow
Hey @Sophivorus thanks for reaching out. There is some technical documentation here that hopefully will give you sufficient guidance to making the Ambox template on es.wiki mobile-friendly: Making page issues (ambox templates) mobile friendly. It was written by @Jdlrobson who may be able to provide extra guidance.