border only shows when admin mode(login)

hi there,
I added css like

.tablepress-id-11 tr,
.tablepress-id-11 tbody td,
.tablepress-id-11 thead th,
.tablepress-id-11 tfoot th {
	border: 1px solid #000000 !important;
}

When I reviewed my post, it was totally fine.(I mean if I was login me site)
However, when I log out and view this post like a regular user, the border I setup doesn’t show

My post is

I used the CSS for the first and second tables.
Hopefully, someone can tell me what I did wrong.
Thanks.

The page I need help with: [log in to see the link]