subcategories and HTML in Marker description

Hi, I’ve bought the Pro Google Maps Easy, and I like it, but I have some problems:
1. I would like to create a map of climbing sites in my country, and all the sites have some climbing sectors, and the sectors have some climbing routes, so I’ve made a category “sites” and category “sectors”, which is a sub-category of “sites”. So my questions are:
– Is it possible to have some sub-categories in the main category?
– Can the sub-category be visible after clicking on the main category?

2. In the marker’s description I have a name of the climbing sector, and then I would like to have a list of climbing routes, but the list should be visible just after the click on the name of the list. I use the HTML tag – <details> , it’s working fine, but when I click “save marker” there is a space (sometimes more) between the name of the sector and the list, so the marker’s description is too big. This is an example:

sektor Lietacky 

<details open=””> <summary>List</summary>

1. Test 1
2. Test 2
3. Test 3

</details>

Can you please help me? Shall I use some other tag?

Palo