How do I make the header transparent only on first slide of one picture?

Hi there. I have a problem om my trial page. My page is a one pager in the theme almar . I would like to code the header so that its only transparent on the first slide with a picture, and then solid. 
Heres a reference: https://www.psykologblaagaardsplads.dk/

I hope someone can help! :))) 

best, Julie 

5 hours ago, Juliestub said:

Hi there. I have a problem om my trial page. My page is a one pager in the theme almar . I would like to code the header so that its only transparent on the first slide with a picture, and then solid. 
Heres a reference: https://www.psykologblaagaardsplads.dk/

I hope someone can help! :))) 

best, Julie 

Here is the current stage I check on your site

Transparent on top:

Solid header when you scroll down

Does it need some additional configuration?

Yes, this is the referencepage i would like to copy. 

My page is: https://springtail-heron-ra2z.squarespace.com/config/pages

Do you know how to code the header as on the reference page? 

/ Julie

This first picture is how my page looks, with a solid color on header, and i would like it to be transparent, but only on the top

26 minutes ago, Juliestub said:

This first picture is how my page looks, with a solid color on header, and i would like it to be transparent, but only on the top

Have you tried editing the header and choose the style of dynamic?

Yes, then its not solid on the next sections, which makes it hard to read the text of both the page and the header

https://www.loom.com/share/76145635f2024bb19070aa3d15cfbe39

See the video