update elements and fix some bugs

lib/src/paper-material/paper-material.html

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 @license
 Copyright (c) 2015 The Polymer Project Authors. All rights reserved.
 This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
 The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
 The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
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 <link rel="import" href="../polymer/polymer.html">
 <link rel="import" href="../paper-styles/shadow.html">
 
 <!--
+Material design: [Cards](https://www.google.com/design/spec/components/cards.html)
 
 `paper-material` is a container that renders two shadows on top of each other to
 create the effect of a lifted piece of paper.
 
 Example:
 
     <paper-material elevation="1">
       ... content ...
     </paper-material>
 
 @group Paper Elements
-@class paper-material
 @demo demo/index.html
 -->
 
 <dom-module id="paper-material">
-  <style>
-    :host {
-      display: block;
-      position: relative;
-    }
+  <template>
+    <style>
+      :host {
+        display: block;
+        position: relative;
+      }
 
-    :host([animated]) {
-      @apply(--shadow-transition);
-    }
+      :host([animated]) {
+        @apply(--shadow-transition);
+      }
 
-    :host([elevation="1"]) {
-      @apply(--shadow-elevation-2dp);
-    }
+      :host([elevation="1"]) {
+        @apply(--shadow-elevation-2dp);
+      }
 
-    :host([elevation="2"]) {
-      @apply(--shadow-elevation-4dp);
-    }
+      :host([elevation="2"]) {
+        @apply(--shadow-elevation-4dp);
+      }
 
-    :host([elevation="3"]) {
-      @apply(--shadow-elevation-6dp);
-    }
+      :host([elevation="3"]) {
+        @apply(--shadow-elevation-6dp);
+      }
 
-    :host([elevation="4"]) {
-      @apply(--shadow-elevation-8dp);
-    }
+      :host([elevation="4"]) {
+        @apply(--shadow-elevation-8dp);
+      }
 
-    :host([elevation="5"]) {
-      @apply(--shadow-elevation-16dp);
-    }
-  </style>
-  <template>
+      :host([elevation="5"]) {
+        @apply(--shadow-elevation-16dp);
+      }
+    </style>
+
     <content></content>
   </template>
 </dom-module>
 <script>
   Polymer({
     is: 'paper-material',
 
     properties: {
-
       /**
        * The z-depth of this element, from 0-5. Setting to 0 will remove the
        * shadow, and each increasing number greater than 0 will be "deeper"
        * than the last.
        *
        * @attribute elevation
        * @type number
        * @default 1
        */
       elevation: {
@@ skipping 11 matching lines @@
        * @default false
        */
       animated: {
         type: Boolean,
         reflectToAttribute: true,
         value: false
       }
     }
   });
 </script>