Update Postman Link (#309)

Author: wachugamaina

pages/service-usages/basic-usages.md

@@ -1,6 +1,6 @@
 ## Basic Usages
 
-[Run in Postman](https://app.getpostman.com/run-collection/522bf43d2b5f9f09f7ee){:.postman}
+[Run in Postman](https://app.getpostman.com/run-collection/522bf43d2b5f9f09f7ee)
 
 For usage of advanced scenarios, please refer to [Trippin Advanced Usages](service-usages/trippin-advanced-usages/).
 

public/css/site.css

@@ -348,13 +348,6 @@ pre {
   background-color: #c34113;
 }
 
-.postman {
-  border-radius: 3px;
-  background: #d23714;
-  padding: 5px;
-  color: white;
-}
-
 /* Mouse navigation.*/
 .postman:hover {
   color: white;
@@ -386,4 +379,4 @@ strong {
   color: #000;
   font-weight: bold;
   font-size: 1.5rem;
-}
+}