JSFiddle - React, Tailwind, and code Playground

HTML

<div class="round">
    <iframe width="300" height="300" frameborder="0" scrolling="no" marginheight="0" marginwidth="0" src="http://maps.google.ru/maps?f=q&amp;source=s_q&amp;hl=ru&amp;geocode=&amp;q=%D0%9E%D0%B4%D0%B5%D1%81%D1%81%D0%B0&amp;aq=&amp;sll=55.354135,40.297852&amp;sspn=22.940419,45.74707&amp;ie=UTF8&amp;hq=&amp;hnear=%D0%9E%D0%B4%D0%B5%D1%81%D1%81%D0%B0,+%D0%9E%D0%B4%D0%B5%D1%81%D1%81%D0%BA%D0%B0%D1%8F+%D0%BE%D0%B1%D0%BB%D0%B0%D1%81%D1%82%D1%8C,+%D0%A3%D0%BA%D1%80%D0%B0%D0%B8%D0%BD%D0%B0&amp;ll=46.484583,30.7326&amp;spn=0.107786,0.178699&amp;t=m&amp;z=13&amp;output=embed"></iframe><br /><small><a href="http://maps.google.ru/maps?f=q&amp;source=embed&amp;hl=ru&amp;geocode=&amp;q=%D0%9E%D0%B4%D0%B5%D1%81%D1%81%D0%B0&amp;aq=&amp;sll=55.354135,40.297852&amp;sspn=22.940419,45.74707&amp;ie=UTF8&amp;hq=&amp;hnear=%D0%9E%D0%B4%D0%B5%D1%81%D1%81%D0%B0,+%D0%9E%D0%B4%D0%B5%D1%81%D1%81%D0%BA%D0%B0%D1%8F+%D0%BE%D0%B1%D0%BB%D0%B0%D1%81%D1%82%D1%8C,+%D0%A3%D0%BA%D1%80%D0%B0%D0%B8%D0%BD%D0%B0&amp;ll=46.484583,30.7326&amp;spn=0.107786,0.178699&amp;t=m&amp;z=13" style="color:#0000FF;text-align:left">Просмотреть увеличенную карту</a></small>
    
</div>

CSS

.round {
    height: 300px;
    width: 300px;
    border-radius: 50%;
    background: yellow;
}

.round iframe {
    border-radius: 50%
}