CSS crushes when changing checkout page

Hi there! I get this stuff happening:

I want to change the looks of the checkout page in the frontend_custom.css. So, for example, its the Email line. So, in Chromium, i click on the Inspect Element and see, that its class is : "hikashop_registration_email_line".
Next, I add these lines to the .css file :

(I also tried this:
span.hikashop_registration_email_line{
font-size:16px;
{
but it didnt work either)

Saving the changes, and everything crushes (see 1st screnshot)


I am removing the changes and everything works fine (see 2nd screenshot)




Actually, if I am trying to change anything on the checkout page, it crushes just like on the 1st screenshot. Also, the looks of the pop-up notice when a product is added to the cart crushes too and it looks pretty ugly. So, the list of things crushing :

1) Filters titles
2) Cursors disappear in the filters
3) Colour of the price
4) Pop-up notice
5) Pages to navigate through the catalogue in the bottom of the page
thats all i noticed yet.

I dont know. Maybe it is not a bug and I am doing the wrong thing, but I changed many .css issues like that and everything went fine.

That's hilarious. I was trying about 10 variants of writing that rule with different selectors in order to make sure that its really a bug. And that was a waste cuz I misspelled one time. Thats rediculous. Lol. Thanks. it works now:D