Hide 'minutes' and 'seconds' of duration variable on record producer

[JJG]

Hello,

I have a duration field on a record producer. I need to hide the minutes and seconds part of the duration field. I tried using the standard method which is an on load client script:

g_form.getElement('Insert element name here').style.display = 'none';

However, I have been hitting a wall. I cannot find the name of the element (See Pic below) Any tips? What should I put for the element name?

[Harsh Vardhan]

dom manipulation does not work on portal. may i know the use case, why are you hiding it ?

[JJG]

The users are not very tech-savvy, I need to hide the minute and seconds fields to prevent them from accidentally inputting data there. It could cause issues in the long run. 

[Harsh Vardhan]

you can try with single line text variable . 

DOM will not work here on portal.  

[Harsh Vardhan]

if its only for number value need to present then you can use single line text variable. 

set validation regex as number.

screenshot for reference.