How should one dress when visiting a 5* hotel?

I plan to visit Carlsbad in Czech Republic, also called Karlovy Vary.

It's a spa city, full of Slavic, especially Russian people from what I have heard.

I have no experience with 5* hotels and how do people dress there, I could not find any dress code for the hotels I am deciding to choose from.

Hotel Imperial 5*
Hotel Imperial 5*

Are jeans allowed when paired with a nice top and heels for example?
Can I wear a maxi bodycon dress to a dinner?

Thank you for your advice/tips!

How should one dress when visiting a 5* hotel?
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