Here is my folder tree looks like. Hope the snippet is somewhat you need.
I use default theme with colors in Flexoki palette.
.tree-item-self.nav-folder-title.fn-is-active,
.tree-item-self.nav-file-title.fn-is-active,
.nav-folder-title.is-active,
.nav-file-title.is-active {
background-color: var(--background-modifier-hover);
}
.nav-files-container>div {
>.tree-item:nth-of-type(8n+1) * {
--folder-color: var(--color-pink);
--folder-color-rgb: var(--color-pink-rgb);
}
>.tree-item:nth-of-type(8n+2) * {
--folder-color: var(--color-red);
--folder-color-rgb: var(--color-red-rgb);
}
>.tree-item:nth-of-type(8n+3) * {
--folder-color: var(--color-orange);
--folder-color-rgb: var(--color-orange-rgb);
}
>.tree-item:nth-of-type(8n+4) * {
--folder-color: var(--color-yellow);
--folder-color-rgb: var(--color-yellow-rgb);
}
>.tree-item:nth-of-type(8n+5) * {
--folder-color: var(--color-green);
--folder-color-rgb: var(--color-green-rgb);
}
>.tree-item:nth-of-type(8n+6) * {
--folder-color: var(--color-cyan);
--folder-color-rgb: var(--color-cyan-rgb);
}
>.tree-item:nth-of-type(8n+7) * {
--folder-color: var(--color-blue);
--folder-color-rgb: var(--color-blue-rgb);
}
>.tree-item:nth-of-type(8n+8) * {
--folder-color: var(--color-purple);
--folder-color-rgb: var(--color-purple-rgb);
}
>.tree-item {
* {
--nav-item-color-active: var(--folder-color);
--nav-item-background-active: var(--background-modifier-hover);
--nav-item-background-hover: rgba(var(--folder-color-rgb), var(--folder-hover-opacity));
--nav-indentation-guide-color: rgba(var(--folder-color-rgb), var(--folder-indentation-opacity));
}
.tree-item-children {
border-inline-start: var(--nav-indentation-guide-width) solid var(--nav-indentation-guide-color);
}
.nav-folder-title {
--nav-item-color-hover: var(--folder-color);
--nav-collapse-icon-color: var(--folder-color);
--nav-item-color: var(--folder-color);
}
.nav-file-title:hover,
.tree-item-self.fn-is-active:hover {
background-color: rgba(var(--folder-color-rgb), var(--folder-hover-opacity));
}
}
}
