Procedure Step by Step: 


1. Go to your blogger's dashboard and choose your desired blog which you want to customize. 
2. Now in the left menu click on "Theme" 

3. also, click the button "Customize" under Live on Blog. 
4. In the left side menu click on "Advance".


5. Then, Click on "Add CSS" button and paste the copied code in the text box area and click on "Apply to blog" to save your changes.

.code { background:#f5f8fa; background-repeat:no-repeat; border: solid #5C7B90; border-width: 1px 1px 1px 20px; color: #000000; font: 13px 'Courier New', Courier, monospace; line-height: 16px; margin: 10px 0 10px 10px; max-height: 200px; min-height: 16px; overflow: auto; padding: 28px 10px 10px; width: 90%; } .code:hover { background-repeat:no-repeat; }



6. whenever we would like to create a post with programming code or syntax than we need to write that code under following div.

<div class="code">
Paste your code/syntax here
</div>

7. Save your post and preview.