Bug Confirmation Message Sent

Hi everybody,

i use wordpress 4.4.2 with Zerif lite Theme and PirateForms.
My website use two different languages with Polylang plyugin and the confirmation message :

Thanks, your email was sent successfully!

isn’t translate. I can’t see this sentence in my translation pannel wheareas i can translate all fields.

An other little thing. This message still show all time on my homepage so i decide to use css to hide it after few seconds.
If i can help anyone this is my source code :

#contact .pirate_forms_thankyou_wrap {
-moz-animation: cssAnimation 0s ease-in 5s forwards;
/* Firefox */
-webkit-animation: cssAnimation 0s ease-in 5s forwards;
/* Safari and Chrome */
-o-animation: cssAnimation 0s ease-in 5s forwards;
/* Opera */
animation: cssAnimation 0s ease-in 5s forwards;
-webkit-animation-fill-mode: forwards;
animation-fill-mode: forwards;
}
@keyframes cssAnimation {
to {
width:0;
height:0;
overflow:hidden;
}
}
@-webkit-keyframes cssAnimation {
to {
width:0;
height:0;
visibility:hidden;
}
}

If u can tell me how fix translation bug, i will modify source code while u push next updates.

Ps : Sorry for my bad english 😉

https://ww.wp.xz.cn/plugins/pirate-forms/