CODE EXAMPLE FOR CSS

gradient border

.btn-gradient-border {
  color: rgb(var(--text-color));
  border: 2px double transparent;
  background-image: linear-gradient(rgb(13, 14, 33), rgb(13, 14, 33)), radial-gradient(circle at left top, rgb(1, 110, 218), rgb(217, 0, 192));
  background-origin: border-box;
  background-clip: padding-box, border-box;
}