Edit newsletter email border colour

Site URL: https://miguelmateas.com/thecreativescientist

Hello lovely SquareSpace forum peeps!

I'm trying to customise the border colour of the email / newsletter block, as per the screenshot below. I've been using the 2 versions of the code you can see below, plus the 2 combined. They all appear to work when I'm typing the code into the Custom CSS box, but then doesn't seem to stick once I save and open that page in another tab. 

Any ideas would be really appreciated, thank you!

Miguel

---

Version 1

/* Newsletter email border colour */

.light .sqs-block-newsletter .newsletter-form-field-element {
    border: 2px solid rgbargba(0, 205, 0, 1);
}

version 2

/* Newsletter email border colour */

.light .sqs-block-newsletter .newsletter-form-field-element {
    border-color: rgba(0, 205, 0, 1);
      border-width: 2px 
}

Just figured it out 🙂

/* Newsletter email border colour */

#email-yui_3_17_2_1_1589395651100_4462-field {
    border-color: rgba(0, 205, 0, 1);
      border-width: 2px; 
}