Looks like left padding of .paragraph-box adds spacing at the right, and top padding adds spacing at the bottom.
.virtualized-scroll-pane .styled-text-area .paragraph-box {
-fx-padding: 15px 90px 60px 80px;
}
(look at horizontal scrollbar)

.virtualized-scroll-pane .styled-text-area .paragraph-box {
-fx-padding: 15px 0 60px 80px;
}

.virtualized-scroll-pane .styled-text-area .paragraph-box {
-fx-padding: 15px 0 60px 0;
}

.virtualized-scroll-pane .styled-text-area .paragraph-box {
-fx-padding: 15px 0 0 0;
}

Looks like left padding of
.paragraph-boxadds spacing at the right, and top padding adds spacing at the bottom.(look at horizontal scrollbar)