--- a/toolkit/content/aboutTelemetry.css
+++ b/toolkit/content/aboutTelemetry.css
@@ -16,33 +16,30 @@ body {
 
 #categories {
   min-width: 250px;
   padding-top: 0px;
   overflow-y: auto;
 }
 
 #category-raw {
-  border-top: 1px solid var(--in-content-header-border-color);
+  background-color: var(--in-content-page-background);
   box-sizing: border-box;
-  background-color: inherit;
   min-width: inherit;
   position: absolute;
   bottom: 0;
   left: 0;
 }
 
 .heading {
   display: flex;
   flex-direction: column;
   font-size: 18px;
-  color: var(--in-content-category-text);
   pointer-events: none;
   padding: 12px 21px 15px 21px;
-  border-bottom: 1px solid var(--in-content-header-border-color);
 }
 
 .header {
   display: flex;
 }
 
 .header select {
   margin-left: 4px;
@@ -86,48 +83,36 @@ body {
   min-height: 42px;
 }
 
 .category-name {
   padding: 9px 0px;
   vertical-align: middle;
 }
 
-.category.has-subsection {
-  padding-inline-start: 0px;
-}
-
-.category.has-subsection > span {
-  padding-inline-start: 11px;
+.category-subsection {
+  color: var(--in-content-text-color);
+  padding: 8px 0px;
+  padding-inline-start: 16px;
+  display: none;
+  -moz-user-select: none;
 }
 
-.category.has-subsection.selected {
-  border-inline-start: none;
-}
-
-.category-subsection {
-  padding: 9px 0px;
-  padding-inline-start: 30px;
-  display: none;
-  -moz-user-select: none;
+.category-subsection.selected {
+  color: inherit;
 }
 
 .category-subsection::first-letter {
   text-transform: uppercase;
 }
 
 .category.selected > .category-subsection {
   display: block;
 }
 
-.category-subsection.selected {
-  padding-inline-start: 26px;
-  border-inline-start: solid 4px var(--in-content-border-highlight);
-}
-
 .category-name {
   pointer-events: none;
 }
 
 .main-content {
   width: 100%;
   font-size: 18px;
   line-height:1.6;
@@ -147,22 +132,16 @@ section:not(.active) {
 }
 
 #ping-explanation > span {
   cursor: pointer;
   border-bottom-width: 2px;
   border-bottom-style: solid;
 }
 
-#ping-explanation > span:hover {
-  color: var(--in-content-page-color);
-  border-bottom-width: 2px;
-  border-bottom-style: solid;
-}
-
 #ping-picker.hidden {
   display: none;
 }
 
 #ping-picker {
   min-width: 300px;
   position: fixed;
   z-index: 2;