Update 'index.html'

index.html

@@ -19,6 +19,26 @@
                 list-style-type: none;
             }
 
+            /* unvisited link */
+            a:link {
+                color: red;
+            }
+
+            /* visited link */
+            a:visited {
+                color: green;
+            }
+
+            /* mouse over link */
+            a:hover {
+                color: hotpink;
+            }
+
+            /* selected link */
+            a:active {
+                color: blue;
+            }
+
         </style>
 
     </head>