chore: color in MarkdownBlock

Author: atinux

.demo/components/content/MarkdownBlock.vue

@@ -1,4 +1,4 @@
 <!-- This component is used to show Markdown code block examples -->
 <template>
-  <pre class="max-w-full overflow-x-auto"><ContentSlot :use="$slots.default" unwrap="p" /></pre>
+  <pre class="max-w-full overflow-x-auto text-gray-700 dark:text-gray-300"><ContentSlot :use="$slots.default" unwrap="p" /></pre>
 </template>