fix images in csp

content/slides/1337/md/xss.md

@@ -273,9 +273,7 @@ Content-Security-Policy: script-src 'self' https://apis.google.com; frame-src 'n
 
 ## [<i class="fa fa-medkit"></i> **CSP**: Content Security Policy](https://developer.mozilla.org/en-US/docs/Web/Security/CSP/CSP_policy_directives)
 
-<div style="text-align: center">
-  ![CSP](images/xss/csp.png "CSP")
-</div>
+![CSP](images/xss/csp.png "CSP")<!-- .element style="text-align: center" -->
 
 * [<i class="fa fa-newspaper-o"></i> Why is CSP Failing? Trends and Challenges in CSP Adoption](mweissbacher.com/publications/csp_raid.pdf)
 
@@ -305,9 +303,7 @@ $(function() { // on Load jQuery style
 });
 ```
 
-<div style="text-align: center">
-  ![SOP](images/xss/sop.png "SOP")
-</div>
+![SOP](images/xss/sop.png "SOP")<!-- .element style="text-align: center" -->
 
 
 ## [<i class="fa fa-medkit"></i> **SOP**: Same Origin Policy](https://developer.mozilla.org/fr/docs/Web/JavaScript/)