Zoho CRM - How to get Lead Timezone ?

Zoho CRM - How to get Lead Timezone ?

We are connecting Zoho CRM to our Website lead form (Wordpress JetBuilder). We have field for Date/Time selection to book a Free session with our Business. 

We need a way to get the lead timezone, so we are able to set the free session time correctly on Calender.

At the moment, we only ask the lead client for Country (dropdown) and city (free Text). So, we can't depend on the City to run a script and get the timezone.

We are open to any easy idea even changing the form builder to Zoho forms if there is a solution to