JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://assets.calendly.com/assets/external/widget.js" type="text/javascript"></script>
<div class="calendly-inline-widget" data-url="https://calendly.com/andry-heyreliable/30min?hide_gdpr_banner=1" style="height:700px;width:100%;pagging:0;margin:0;"></div>

CSS

body{
  margin: 0;
}

._cUP1np9gMvFQrcPftuf.xahN8AEzyAvQtVj17TPv {
    margin-top: 0;
    margin-bottom: 0;
}

._3efP_GeH5kyBAzqnLzL._kN_bCa3VNYpqFLH311L{
  max-width:initial;
  width:100%;
}