support merge className

Author: MinJieLiu

example/BasicForm.jsx

@@ -101,6 +101,7 @@ class BasicForm extends Component {
         <div className="form-group">
           <label htmlFor="email">Email:</label>
           <Text
+            className="email"
             id="email"
             name="email"
             type="email"

example/BasicForm.scss

@@ -10,12 +10,12 @@
   color: #a94442;
   -webkit-box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075);
   box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075);
-}
 
-.valid-error:focus {
-  border-color: #843534;
-  -webkit-box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 6px #ce8483;
-  box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 6px #ce8483;
+  &:focus {
+    border-color: #843534;
+    -webkit-box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 6px #ce8483;
+    box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 6px #ce8483;
+  }
 }
 
 .valid-error-message {
@@ -29,10 +29,10 @@
   border-color: #3c763d;
   -webkit-box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075);
   box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075);
-}
 
-.valid-success:focus {
-  border-color: #2b542c;
-  -webkit-box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 6px #67b168;
-  box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 6px #67b168;
-}
+  &:focus {
+    border-color: #2b542c;
+    -webkit-box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 6px #67b168;
+    box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 6px #67b168;
+  }
+}