Hello @Luke50
It’s GemPages support team and glad to support you today.
The white space of the header is caused by the logo image containing the space and you should re-upload the logo image or see my suggestions below to remove it:
- Go to Online Store → Theme → Edit code
- Open your theme.liquid theme file
- Paste below code before :
If you require any further information, feel free to contact me.
Best regards,
GemPages Support Team