in many times your theme is good, without responsive. and you want to disable that one.
how you do that?
it’s on viewport meta under the header tagged
the detail of the description of that tagged list below
“<" meta name="viewport" content="width=device-width" ">”
more option as
width The width of the virtual viewport of the device.
device-width The physical width of the device’s screen.
height The height of the “virtual viewport” of the device.
device-height The physical height of the device’s screen.
initial-scale The initial zoom when visiting the page. 1.0 does not zoom.
minimum-scale The minimum amount the visitor can zoom on the page. 1.0 does not zoom.
maximum-scale The maximum amount the visitor can zoom on the page. 1.0 does not zoom.
user-scalable Allows the device to zoom in and out. Values are yes or no.