CSS for input[type="submit"]
<p>Before I start crying, could someone please explain why none of the attempted CSS soltions for styling a submit button have any effect at all? I've gone for <code>font-size: 50px</code> to make it obvious if I hit the right element, which I haven't yet:</p>

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<pre class="snippet-code-css lang-css prettyprint-override"><code> input[type="submit"].wysija-submit  {
        border-radius: 10px;
        border: none;
        box-shadow: none;
        font-family: inherit;
        font-size: 50px!important;
    }
    
    .wysija-submit input[type="submit"] {
        border-radius: 10px;
        border: none;
        box-shadow: none;
        font-family: inherit;
        font-size: 50px!important;
    }
    
    .wysija-submit.wysija-submit-field input[type="submit"] {
        border-radius: 10px;
        border: none;
        box-shadow: none;
        font-family: inherit;
        font-size: 50px!important;
    }</code></pre>
<pre class="snippet-code-html lang-html prettyprint-override"><code>   &lt;input class="wysija-submit wysija-submit-field" type="submit" value="Sign-up"&gt;
    
   </code></pre>
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</p>