title: Change background transparency of Chart.js chart
body: <p>i'm using chart.js wrapped within <a href="http://jtblin.github.io/angular-chart.js/" rel="nofollow">angular-charts.js</a> to create a bar chart in an Ionic framework app.</p>
  
  <p>I want to make the bar background totally opaque.</p>
  
  <p>This the code i have to create the chart.</p>
  
  <pre><code>&lt;canvas id="bar" class="chart chart-bar" data="data" labels="labels" legend="true" series="series" options="{showTooltips: false}" colours="[ '#ffff00',    '#0066ff']"&gt;&lt;/canvas&gt;
  </code></pre>
  
  <p>Have any idea of how could i achieve that?</p>
  
  <p>Thanks a lot!</p>