Update Sky widgets to have more material design

sky/framework/sky-input.sky

Index: sky/framework/sky-input.sky
diff --git a/sky/framework/sky-input.sky b/sky/framework/sky-input.sky
index 2dcd646b0b7c93123deba337dd5feaecbd134dfc..ae49b907005c1ab9d43ca1d80d5d50ce13d404b6 100644
--- a/sky/framework/sky-input.sky
+++ b/sky/framework/sky-input.sky
@@ -10,17 +10,21 @@
   <style>
   :host {
     display: flex;
-    border: 1px solid blue;
-    margin: 5px;
-    padding: 4px;
   }
   #control {
+    margin: 8px;
+    padding: 8px;
+    border-bottom: 1px solid #E7E7E7;
     flex: 1;
     align-self: center;
     height: 1.2em;
     white-space: nowrap;
     overflow: hidden;
   }
+  #control.focused {
+    padding-bottom: 7px;
+    border-bottom: 2px solid #009cf3;
+  }
   </style>
   <div id="control" contenteditable />
 </template>
@@ -57,10 +61,14 @@ class SkyInput extends SkyElement {
   }
 
   void _handleFocus(_) {
+    if (_control)
+      _control.setAttribute('class', 'focused');
     // TODO(abarth): Show the keyboard.
   }
 
   void _handleBlur(_) {
+    if (_control)
+      _control.removeAttribute('class');
     // TODO(abarth): Hide the keyboard.
   }
 }