Rainbow-ifies folders in Obsidian, but only the root folders

Obsidian-Rainbow-Folders-in-Root.css

/* Coloured Folders
A CSS snippet by WebInspectInc
with inspiration from Lithou

This snippet colors the folders in your sidebar based on your theme colors,
with fallbacks in case your theme doesn't specify default colors
This snippet has been modified to only affect only root folders
*/
:root{
    /* folder colours */
    --Fold1: #f39b9b;
    --Fold2: #f0ae59;
    --Fold3: #f1ca5d;
    --Fold4: #9dcd78;
    --Fold5: #8ab6e2;
    --Fold6: #aaa5db;
    --Fold7: #d399cf;
    --Fold8: #cda485;
    --Fold9: #b9c0c7;
    --FoldA: #f0aaaa;
    --FoldB: #f1b86f;
    --FoldC: #7acc93;
    --FoldD: #87c9d9;
    --FoldE: #96abde;
    --FoldF: #eb9fc9;
    --FoldText: #303030;
}

/* Set up explorer container margins */
.nav-files-container{margin: 0px 5px;}


/* Top Level Folder Titles */
.nav-folder.mod-root>.nav-folder-children>.nav-folder>.nav-folder-title {
    color: var(--FoldText);
    /*padding-left: 20px;*/
    margin-top: 5px; /* space between top level sections */
}
.nav-folder.mod-root>.nav-folder-children>.nav-folder>.nav-folder-title:hover {
    color: white;
}

/* active file increase font size and removes normal highlight marker */
.nav-file-title.is-active { 
    color: #000000;
    font-weight: bold;
}

/* Folder Background Colors */

.nav-folder-children .nav-folder .nav-folder-title {
    border-radius: 5px;
    margin-top: 2px;
}


.mod-root > .nav-folder-children > .nav-folder:nth-child(9n+2) > .nav-folder-title {
    background-color: var(--color-red, var(--Fold1));
}
.mod-root > .nav-folder-children > .nav-folder:nth-child(9n+3) > .nav-folder-title {
    background-color: var(--color-orange, var(--Fold2));
}
.mod-root > .nav-folder-children > .nav-folder:nth-child(9n+4) > .nav-folder-title {
    background-color: var(--color-yellow, var(--Fold3));
}
.mod-root > .nav-folder-children > .nav-folder:nth-child(9n+5) > .nav-folder-title {
    background-color: var(--color-green, var(--Fold4));
}
.mod-root > .nav-folder-children > .nav-folder:nth-child(9n+6) > .nav-folder-title {
    background-color: var(--color-cyan, var(--Fold5));
}
.mod-root > .nav-folder-children > .nav-folder:nth-child(9n+7) > .nav-folder-title {
    background-color: var(--color-blue, var(--Fold6));
}
.mod-root > .nav-folder-children > .nav-folder:nth-child(9n+8) > .nav-folder-title {
    background-color: var(--color-purple, var(--Fold7));
}
.mod-root > .nav-folder-children > .nav-folder:nth-child(9n+9) > .nav-folder-title {
    background-color: var(--color-pink, var(--Fold8));
}
.mod-root > .nav-folder-children > .nav-folder:nth-child(9n+10) > .nav-folder-title {
    background-color: var(--Fold9);
}

/*----file explorer smaller fonts & line height----*/
.nav-file-title,
.nav-folder-title {
  cursor: pointer;
  position: relative;
  border-width: 1px;
  border-style: solid;
  border-color: transparent;
  border-image: initial;
  border-radius: 0px;
  display: flex;
  align-items: baseline;
  flex-direction: row;
}

.nav-file-title {
    border-radius: var(--radius-s);
}

.mod-root > .nav-folder-children > .nav-folder > .nav-folder-title {
  color: var(--FoldText);
}
body:not(.is-grabbing) .tree-item-self.nav-folder-title:hover {
/*    color: var(--FoldText);*/
    opacity: 0.6;
}

/*rename*/
.nav-file-title-content.is-being-renamed,
.nav-folder-title-content.is-being-renamed {
  cursor: text;
  border-color: transparent;
  background-color: white;
  color: var(--FoldText);
}

Preview of styling with the Minimal theme/Flexoki color scheme. Notice subfolders do not inherit the styling: