Update README.md

Author: Gio

README.md

@@ -7,7 +7,7 @@
 
 <p align="center">This theme follows lastest GNOME Adwaita style.</p>
 
-<p align="center"><img src="firefox-phosh1.png" width=40% height=40%> <img src="firefox-phosh2.png" width=40% height=40%></p>
+<p align="center"><img src="firefox-phosh1.png" width=30% height=30%> <img src="firefox-phosh2.png" width=30% height=30%></p>
 
 ## Description