config_service: make UI responsive and change colors.

appengine/config_service/ui/src/config-ui/front-page.html

 <!--
   Copyright 2017 The LUCI Authors. All rights reserved.
   Use of this source code is governed under the Apache License, Version 2.0
   that can be found in the LICENSE file.
 -->
 
 <link rel="import" href="../../bower_components/app-layout/app-layout.html">
 <link rel="import" href="../../bower_components/iron-ajax/iron-ajax.html">
 <link rel="import" href="../../bower_components/paper-button/paper-button.html">
 <link rel="import" href="../../bower_components/paper-search/paper-search-bar.html">
 <link rel="import" href="../../bower_components/paper-spinner/paper-spinner.html">
 <link rel="import" href="../../bower_components/paper-styles/shadow.html">
 <link rel="import" href="../../bower_components/polymer/polymer.html">
 
 <link rel="import" href="config-set-card.html">
 
 <dom-module id="front-page">
   <template>
     <style>
       .center {
-        width: 25%;
+        width: 23%;
         margin: auto;
       }
 
       .config-card { 
         padding-bottom: 1%;
         animation: fadein 1.5s;
       }
 
       @keyframes fadein {
         from {opacity: 0}
@@ skipping 114 matching lines @@
         var tempResults = this.configSetList.filter(e => e.config_set.includes(this.query));
         tempResults.sort(function(a, b) {
           return this._formatName(a.config_set).localeCompare(this._formatName(b.config_set));
         }.bind(this));
         this.searchResults = tempResults;
       },
 
     });
   </script>
 </dom-module>