<div class="bg">
  
</div>
.bg {
  width: 350px;
  height: 450px;
  border:2px solid black;
background: radial-gradient(78.4% 23.38% at 50.09% -5.28%, #2126A6 91.15%, #2126A6 91.16%, rgba(0, 10, 253, 0) 93.23%, rgba(0, 10, 255, 0) 100%), #FFFFFF;
}

External CSS

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External JavaScript

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