Form button not showing anymore unless you hover over it

Hello 👋,
I just noticed that suddenly all the newsletter form buttons of my site are not showing up anymore unless you hover over them (see attached screenshots).
I did not introduce any changes to the custom CSS nor modified any of the website form setting, therefore I am wondering what might have caused that issue.

Below is the custom CSS used for the newsletter button.

.primary-button-style-outline .newsletter-form-button.sqs-system-button.sqs-button-element--primary:not(:hover) {
  background: @black !important;
  color: @white !important;
}

URLs with the form button issue:

• https://www.sensorytravelexperiences.com/ (at the very bottom)
• https://www.sensorytravelexperiences.com/newsletter

Thank you very much in advance!

Adria

Thanks a lot! That did the trick 🙌