Logo in header changes size when i scroll down

When I scroll down, (it is a sticky menu), the logo decreases automatically its size, like this:

Hello,

Can you please provide a link to your website in order to let me check your logo image?

You can use some link shortener if you don’t want to leave the link to your site in this topic.

Kind Regards, Roman.
aThemes Support

Hi Roman, the website is not up yet, since it is not finalised.

it looks like this, the top image is normal size, and the bottom image is reduced automatic

Hello,

I don’t think that I can provide much help here without a link, unfortunately. I have to at least inspect your header code with the browser tools. Hope for your understanding.

Kind Regards, Roman.
aThemes Support

Yes I understand, i’m not sure if this is the info you wanted to see…

Hello,

Yes I understand, i’m not sure if this is the info you wanted to see…

Thank you, but that screensot is not enough, unfortunately.

Kind Regards, Roman.
aThemes Support