How to change theme into circular thumbnail in Coloris?

I’m using latest version of coloris and looking at the provided examples page I need to make component with
a ‘circular thumbnail’ theme.

<input type="text" id="accent_color" name="accent_color"
  class="accent_color"
  value="{{ $accentColor }}" data-coloris>

I tried to change theme of the component with this code:

<script src="/js/coloris.min.js"></script>
<script>
  $(document).ready(function() {
    Coloris.setInstance('#accent_color', { 
      theme: 'polaroid', 
      themeMode: 'dark',   
      alpha: true 
    });
    // ...

Using that code, the dark theme is applied, but not theme – it is still default:

enter image description here

Which is the correct way to assign ‘circular thumbnail’ theme?