fix(cc-dark-theme): improve dark theme

- Fixed canned response row hover background color.
- Fixed background color of the nested thread view "{num} More comments"
  button.

Fixed: twpowertools:178
Change-Id: I758a997a69319fc41dacd4a7363fe94db0b81dc4
diff --git a/src/ccDarkTheme/components/_canned-responses.scss b/src/ccDarkTheme/components/_canned-responses.scss
index 63996ae..2d07bb8 100644
--- a/src/ccDarkTheme/components/_canned-responses.scss
+++ b/src/ccDarkTheme/components/_canned-responses.scss
@@ -1,31 +1,39 @@
-ec-canned-responses .filter-label,
-    ec-canned-responses ec-canned-response-row .name {
-  color: var(--TWPT-primary-text)!important;
-}
+ec-canned-responses {
+  .filter-label,
+      ec-canned-response-row .name {
+    color: var(--TWPT-primary-text)!important;
+  }
 
-ec-canned-responses .label-row,
-    ec-canned-responses ec-canned-response-row .snippet,
-    ec-canned-responses ec-canned-response-row .tag .content,
-    ec-canned-responses ec-canned-response-row .TWPT-tag .TWPT-content {
-  color: var(--TWPT-secondary-text)!important;
-}
+  .label-row,
+      ec-canned-response-row .snippet,
+      ec-canned-response-row .tag .content,
+      ec-canned-response-row .TWPT-tag .TWPT-content {
+    color: var(--TWPT-secondary-text)!important;
+  }
 
-ec-canned-responses ec-canned-response-row .header.closed:hover,
-    ec-canned-responses ec-canned-response-row .header.closed:focus,
-    ec-canned-responses ec-canned-response-row .header.closed:hover .toolbar,
-    ec-canned-responses ec-canned-response-row .header.closed:focus .toolbar,
-    ec-canned-responses ec-canned-response-row material-expansionpanel:not(.expanded) .main-header:focus-within,
-    ec-canned-responses ec-canned-response-row material-expansionpanel:not(.expanded) .main-header:hover {
-  background-color: var(--TWPT-active-background)!important;
-}
+  material-expansionpanel:not(.expanded) .main-header:focus-within {
+    background-color: var(--TWPT-active-background)!important;
+  }
 
-ec-canned-responses .filter-row,
-    ec-canned-responses .label-row,
-    ec-canned-responses ec-canned-response-row material-expansionpanel {
-  border-bottom-color: var(--TWPT-subtle-border)!important;
-}
+  ec-canned-response-row {
+    .header:hover,
+        .header.closed:focus,
+        .header.closed:hover .toolbar,
+        .header.closed:focus .toolbar,
+        material-expansionpanel:not(.expanded) .main-header:focus-within,
+        material-expansionpanel:not(.expanded) .main-header:hover {
+      background-color: var(--TWPT-active-background)!important;
+    }
+  }
 
-ec-canned-responses .create-button {
-  background: #0842a0!important;
-  color: #d3e3fd!important;
+  .filter-row,
+      .label-row,
+      ec-canned-response-row material-expansionpanel {
+    border-bottom-color: var(--TWPT-subtle-border)!important;
+  }
+
+  .create-button {
+    background: #0842a0!important;
+    color: #d3e3fd!important;
+  }
 }
diff --git a/src/ccDarkTheme/vendors/google/_thread.scss b/src/ccDarkTheme/vendors/google/_thread.scss
index e29c25a..86b370b 100644
--- a/src/ccDarkTheme/vendors/google/_thread.scss
+++ b/src/ccDarkTheme/vendors/google/_thread.scss
@@ -209,6 +209,14 @@
   color: var(--TWPT-interop-secondary-text);
 }
 
+.scTailwindThreadMessagegapmore-nested-replies {
+  background: #3c4043;
+}
+
+.scTailwindThreadMessagegapmore-nested-replies-divider {
+  background: #27282b;
+}
+
 .scTailwindThreadPesignupdialogclose-button-row button {
   color: #fff;
 }