Can we store smtp.js token in clear text in our code?

I am creating my portfolio (in html, css and js) which has a “contact” page with a form.
I would have liked it to be possible, from this form, to send me an email. So I did some research and I found an api that seems to do what I want: Smtp.js.
This api asks us to create a token in order not to enter the login and the password of our mailbox.
My question is: can we store this token in clear text in our code without risk and if not what to do?