Kiran  Yep, is the one in the guide:

#hu-footer-input-mobile .hu-input-box .hu-input-back{
 visibility: hidden;
 overflow: hidden;
}

.back-button{
display: none;
}
 LEANDRO MEDEIROS  Thank you, Radio button is the solution for my case.
I promise: I will slowly stop asking such trivial questions. Thanks again!
Ops, looks like there was a work around about that, sorry... I just found it now! 🙂
https://landbot.helpdocs.io/article/6nwgz94hm7-direct-the-flow-of-your-bot-based-on-external-parameters
Hi guys, I was looking for this exact operation. How can we empty a var?
 LEANDRO MEDEIROS  Thank for your patience.
I'm used to check conditions at the begin in any other bot platform, so I was looking for that. 

 LEANDRO MEDEIROS  What I'd like to do is avoiding the "Tap here to start" for each opt-in, instead I'd need start checking variables with conditions. Is this possible?
 LEANDRO MEDEIROS  Thanks Leandro. I'm looking for a way to check if some vars has some values and drive the conversation accordingly inside Landbot.
Passing hidden fields gives vars some values, but how could I test theese values inside the flow, as first action?
Thanks again!
I'm new to Landbot V3, but happy to help if you need more users 🙂