docs: update stack graphic (#18532)

docs/docs/get_started/introduction.mdx

@@ -14,7 +14,16 @@ This framework consists of several parts.
 - **[LangServe](/docs/langserve)**: A library for deploying LangChain chains as a REST API.
 - **[LangSmith](/docs/langsmith)**: A developer platform that lets you debug, test, evaluate, and monitor chains built on any LLM framework and seamlessly integrates with LangChain.
 
-![Diagram outlining the hierarchical organization of the LangChain framework, displaying the interconnected parts across multiple layers.](/svg/langchain_stack.svg "LangChain Framework Overview")
+import ThemedImage from '@theme/ThemedImage';
+
+<ThemedImage
+  alt="Diagram outlining the hierarchical organization of the LangChain framework, displaying the interconnected parts across multiple layers."
+  sources={{
+    light: '/svg/langchain_stack.svg',
+    dark: '/svg/langchain_stack_dark.svg',
+  }}
+  title="LangChain Framework Overview"
+/>
 
 Together, these products simplify the entire application lifecycle:
 - **Develop**: Write your applications in LangChain/LangChain.js. Hit the ground running using Templates for reference.