title: tkinter ttk widgets ignoring background color?
body: <p>I'm using <code>tkinter</code>'s themed (<code>ttk</code>) GUI toolkit for an application. Trying to apply some uniform styling to the widgets in the main window:</p>
  
  <pre><code>s = ttk.Style()
  s.configure('.', background='#eeeeee')
  s.configure('.', font=('Helvetica', 14))
  self.configure(background='#eeeeee')
  </code></pre>
  
  <p>The font change works great, but for some reason the widgets (i.e. <code>ttk.Label</code> and <code>ttk.Button</code>) don't seem to reflect the background change, which is pretty obvious visually due to contrast between the window's background and the widget's. If I check what it's set to:</p>
  
  <pre><code>label1.cget('background')
  </code></pre>
  
  <p>it returns <code>''</code>, so clearly it's not being set, but I don't understand what's wrong given the docs for <a href="https://infohost.nmt.edu/tcc/help/pubs/tkinter/web/ttk-Label.html" rel="noreferrer">ttk.Label</a> and <a href="https://infohost.nmt.edu/tcc/help/pubs/tkinter/web/ttk-style-layer.html" rel="noreferrer">styles</a>. Trying to set the background for a single label directly:</p>
  
  <pre><code>label1.configure(background='#eeeeee')
  </code></pre>
  
  <p>also doesn't work (i.e. no change).
  Any ideas?</p>