Calendar does not show on mobile version to make reservation

Hello!

I just finished setting all the plugin settings and it seems that works perfectly on the computer and laptop version. However, on tablet version the calendar can’t be seen completely since it is too big, and on mobile phone version I can not see it at all. Is this plugin design responsive or not? If so, how can I fix this problem or how can I make a different design for smaller screens?

I can not understand why it disappears while I access to the reservation page on my phone. However, I feel that if I could see it, the design would not fit the screen at all like in tablet version.

Could you help me, please?

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