In addition to what Greyelf said, SugarCube has some built-in icons you can use. So you could add a right-arrow to your links like this:
.link-internal:before {
content: "\e822\00a0";
font-family: tme-fa-icons;
font-style: normal;
font-weight: 400;
font-variant: normal;
text-transform: none;
line-height: 1;
width: 13px;
margin: auto;
padding-left: 2px;
speak: none;
}
Enjoy! 