Update TodoMVC based on https://github.com/polymer/todomvc

samples/third_party/todomvc/web/elements/td_todos.css

-html,
-body {
-  margin: 0;
-  padding: 0;
+/* base.css overrides */
+
+@host {
+  * {
+    display: block;
+    position: relative;
+  }
 }
 
 button {
   margin: 0;
   padding: 0;
   border: 0;
   background: none;
   font-size: 100%;
   vertical-align: baseline;
   font-family: inherit;
   color: inherit;
   -webkit-appearance: none;
-  -moz-appearance: none;
+  /*-moz-appearance: none;*/
   -ms-appearance: none;
   -o-appearance: none;
-  /*appearance: none; */
+  appearance: none;
 }
 
-body {
-  font: 14px 'Helvetica Neue', Helvetica, Arial, sans-serif;
-  line-height: 1.4em;
-  background: #eaeaea url('bg.png');
-  color: #4d4d4d;
-  width: 550px;
-  margin: 0 auto;
-  -webkit-font-smoothing: antialiased;
-  -moz-font-smoothing: antialiased;
-  -ms-font-smoothing: antialiased;
-  -o-font-smoothing: antialiased;
-  /* font-smoothing: antialiased; */
+input::-webkit-input-placeholder {
+  font-style: italic;
 }
 
-/*
-TODO(jmesserly): we should try to restore the original CSS file.
-Ours has diverged and some features aren't working anymore, mainly due to the
-extra nodes we introduce for items.
-*/
+input::-moz-placeholder {
+  font-style: italic;
+  color: #a9a9a9;
+}
+
+input:-ms-input-placeholder, #new-todo:-ms-input-placeholder {
+  font-style: italic;
+  color: #a9a9a9;
+}
 
 #todoapp {
   background: #fff;
   background: rgba(255, 255, 255, 0.9);
-  margin: 130px 0 40px 0;
+  /*margin: 130px 0 40px 0;*/
+  margin: 0 0 40px 0;
   border: 1px solid #ccc;
   position: relative;
   border-top-left-radius: 2px;
   border-top-right-radius: 2px;
   box-shadow: 0 2px 6px 0 rgba(0, 0, 0, 0.2),
         0 25px 50px 0 rgba(0, 0, 0, 0.15);
 }
 
 #todoapp:before {
   content: '';
   border-left: 1px solid #f5d6d6;
   border-right: 1px solid #f5d6d6;
   width: 2px;
   position: absolute;
   top: 0;
   left: 40px;
   height: 100%;
 }
 
-input::-webkit-input-placeholder {
-  font-style: italic;
-}
-
-input:-moz-placeholder {
-  font-style: italic;
-  color: #a9a9a9;
-}
-
-.title {
-  position: absolute;
-  top: -120px;
-  width: 100%;
-  font-size: 70px;
-  font-weight: bold;
-  text-align: center;
-  color: #b3b3b3;
-  color: rgba(255, 255, 255, 0.3);
-  text-shadow: -1px -1px rgba(0, 0, 0, 0.2);
-  /*-webkit-text-rendering: optimizeLegibility;*/
-  -moz-text-rendering: optimizeLegibility;
-  -ms-text-rendering: optimizeLegibility;
-  -o-text-rendering: optimizeLegibility;
-  text-rendering: optimizeLegibility;
-}
-
 #header {
   padding-top: 15px;
   border-radius: inherit;
 }
 
 #header:before {
   content: '';
   position: absolute;
   top: 0;
   right: 0;
@@ skipping 29 matching lines @@
   box-shadow: inset 0 -1px 5px 0 rgba(0, 0, 0, 0.2);
   -webkit-box-sizing: border-box;
   -moz-box-sizing: border-box;
   -ms-box-sizing: border-box;
   -o-box-sizing: border-box;
   box-sizing: border-box;
   -webkit-font-smoothing: antialiased;
   -moz-font-smoothing: antialiased;
   -ms-font-smoothing: antialiased;
   -o-font-smoothing: antialiased;
-  /*font-smoothing: antialiased;*/
+  /* font-smoothing: antialiased; */
 }
 
 #new-todo {
   padding: 16px 16px 16px 60px;
   border: none;
   background: rgba(0, 0, 0, 0.02);
   z-index: 2;
   box-shadow: none;
 }
 
@@ skipping 26 matching lines @@
 #toggle-all:checked:before {
   color: #737373;
 }
 
 #todo-list {
   margin: 0;
   padding: 0;
   list-style: none;
 }
 
-/*
-TODO(jmesserly): fix this. It's broken in our sample.
+#todo-list li {
+  position: relative;
+  font-size: 24px;
+  border-bottom: 1px dotted #ccc;
+}
 
-#todo-list todo-row:last-child .todo-item {
+#todo-list li:last-child {
   border-bottom: none;
 }
-*/
 
-/*
-TODO(jmesserly): it seems to be impossible to have selectors that span a
-ShadowRoot transition, even with allow-author-styles set. Various workarounds
-are included in the code below.
-*/
-.edit.editing {
-  display: block;
-  width: 506px;
-  padding: 13px 17px 12px 17px;
-  margin: 0 0 0 43px;
-}
-
-.edit-label {
-  word-break: break-word;
-  margin: 15px 15px 15px 60px;
-  display: inline-block;
-  line-height: 1.2;
-  -webkit-transition: color 0.4s;
-  -moz-transition: color 0.4s;
-  -ms-transition: color 0.4s;
-  -o-transition: color 0.4s;
-  transition: color 0.4s;
-}
-
-.edit-label {
-  text-decoration: inherit;
+#todo-list li.editing {
+  border-bottom: none;
+  padding: 0;
 }
 
 #footer {
   color: #777;
   padding: 0 15px;
   position: absolute;
   right: 0;
   bottom: -31px;
   left: 0;
+  height: 20px;
   z-index: 1;
   text-align: center;
 }
 
 #footer:before {
   content: '';
   position: absolute;
   right: 0;
   bottom: 31px;
   left: 0;
-  height: 100px;
+  height: 50px;
   z-index: -1;
   box-shadow: 0 1px 1px rgba(0, 0, 0, 0.3),
         0 6px 0 -3px rgba(255, 255, 255, 0.8),
         0 7px 1px -3px rgba(0, 0, 0, 0.3),
-        0 42px 0 -6px rgba(255, 255, 255, 0.8),
-        0 43px 2px -6px rgba(0, 0, 0, 0.2);
+        0 43px 0 -6px rgba(255, 255, 255, 0.8),
+        0 44px 2px -6px rgba(0, 0, 0, 0.2);
 }
 
 #todo-count {
   float: left;
   text-align: left;
 }
 
 #filters {
   margin: 0;
   padding: 0;
   list-style: none;
   position: absolute;
   right: 0;
   left: 0;
 }
 
 #filters li {
   display: inline;
 }
 
 #filters li a {
   color: #83756f;
   margin: 2px;
   text-decoration: none;
 }
 
-#filters li a.selected {
+#filters li.polymer-selected a {
   font-weight: bold;
 }
 
 #clear-completed {
   float: right;
+  position: relative;
   line-height: 20px;
   text-decoration: none;
   background: rgba(0, 0, 0, 0.1);
   font-size: 11px;
   padding: 0 10px;
-  position: relative;
   border-radius: 3px;
   box-shadow: 0 -1px 0 0 rgba(0, 0, 0, 0.2);
 }
 
 #clear-completed:hover {
   background: rgba(0, 0, 0, 0.15);
   box-shadow: 0 -1px 0 0 rgba(0, 0, 0, 0.3);
 }
 
-#info {
-  margin: 65px auto 0;
-  color: #a6a6a6;
-  font-size: 12px;
-  text-shadow: 0 1px 0 rgba(255, 255, 255, 0.7);
-  text-align: center;
-}
-
-#info a {
-  color: inherit;
-}
-
-/*
-  Hack to remove background from Mobile Safari.
-  Can't use it globally since it destroys checkboxes in Firefox and Opera
-*/
 @media screen and (-webkit-min-device-pixel-ratio:0) {
   #toggle-all {
     background: none;
+    /*
+      ShadowDOM Polyfill work around for webkit/blink bug
+      https://code.google.com/p/chromium/issues/detail?id=251510
+    */
+    background-color: transparent;
   }
 
   #toggle-all {
     top: -56px;
     left: -15px;
     width: 65px;
     height: 41px;
     -webkit-transform: rotate(90deg);
     transform: rotate(90deg);
     -webkit-appearance: none;
-    -moz-appearance: none;
-    -ms-appearance: none;
-    -o-appearance: none;
-    /*appearance: none; */
+    appearance: none;
   }
 }