Fix content/code font color variables.

packages/codemirror/style/index.css

@@ -42,7 +42,7 @@
 
 
 .CodeMirror.cm-s-jupyter pre {
-  color: var(--jp-code-font-color);
+  color: var(--jp-content-font-color1);
 }
 
 

packages/rendermime/style/index.css

@@ -19,7 +19,7 @@
 
 .jp-RenderedText pre,
 .jp-RenderedHTMLCommon pre {
-  color: var(--jp-ui-font-color0);
+  color: var(--jp-content-font-color1);
   border: none;
   margin: 0px;
   padding: 0px;

packages/theme-dark-extension/style/variables.css

@@ -97,8 +97,6 @@ all of MD as it is not optimized for dense, information rich UIs.
   --jp-code-line-height: 17px;
   --jp-code-padding: 5px;
   --jp-code-font-family: monospace;
-  --jp-code-font-color: white;
-
 
   /* Layout
 

packages/theme-light-extension/style/variables.css

@@ -97,7 +97,6 @@ all of MD as it is not optimized for dense, information rich UIs.
   --jp-code-line-height: 1.307;
   --jp-code-padding: 5px;
   --jp-code-font-family: monospace;
-  --jp-code-font-color: black;
 
   /* Layout