More than one third-level nest causes alignment issues

[leoj3n]

You can see here with CSS from develop branch:

https://canjs-slickmap.glitch.me/index-develop.html

As well as here with CSS copied from the live demo:

https://canjs-slickmap.glitch.me/index.html

[leeoniya]

swapping out to top: calc(-100% + 25px); here works well (at least for the default metrics in this lib):

slickmap/slickmap.css

Lines 229 to 237 in 669e623

	.primaryNav ul ul ul li:before {
	width: calc(50% - 5px) !important;
	height: calc(100% - 2px);
	top: -50%;
	left: 0;
	border-left-width: 2px;
	border-bottom-width: 2px;
	/* border-color: red; */
	}