diff --git a/src/blog/post-3.md b/src/blog/post-3.md
new file mode 100644
index 0000000..720a32c
--- /dev/null
+++ b/src/blog/post-3.md
@@ -0,0 +1,14 @@
+---
+title: 'Why I Write Docstrings'
+pubDate: 2025-05-16
+author: 'Nakahara Daisuke'
+tags: ["programming"]
+---
+
+I try to write docstrings as much as possible for two main reasons. 
+First, they help reviewers understand the roles of functions and classes. 
+Second, I believe that clear, detailed docstrings can enable AI tools to generate code more effectively.
+
+Although I sometimes make mistakes in my docstrings, 
+I think that even imperfect documentation is better than none. 
+Moreover, both reviewers and AI tools can help identify and correct these errors.
diff --git a/src/layouts/MarkdownPostLayout.astro b/src/layouts/MarkdownPostLayout.astro
index 0e7a037..af007b0 100644
--- a/src/layouts/MarkdownPostLayout.astro
+++ b/src/layouts/MarkdownPostLayout.astro
@@ -48,18 +48,19 @@ const optionsForDate = {
   }
 
   .markdown-content {
-      font-family: sans-serif;
-      font-size: 1.2rem;
+    font-family: sans-serif;
+    font-size: 1.2rem;
+    line-height: 2.5;
   }
 
   .markdown-content h1 {
-      font-size: 1.9rem;
+    font-size: 1.9rem;
   }
   .markdown-content h2 {
-      font-size: 1.75rem;
+    font-size: 1.75rem;
   }
   .markdown-content h3 {
-      font-size: 1.5rem;
+    font-size: 1.5rem;
   }
 
 </style>