Aurora shift

Aurora shift: a CSS button. Copy the rules, or the prompt that rebuilds it.

gradientanimatedbackground-positionrounded

CSS
.btn-025 {
  font: 600 15px/1 system-ui,sans-serif;
  color: #fff;
  background: linear-gradient(90deg,#6366f1,#06b6d4,#a855f7,#6366f1);
  background-size: 300% 100%;
  background-position: 0% 0;
  border: 0;
  border-radius: 10px;
  padding: 13px 26px;
  cursor: pointer;
  transition: background-position .6s ease,transform .15s
}
.btn-025:hover {
  background-position: 100% 0
}
.btn-025:focus-visible {
  outline: 3px solid rgba(99,102,241,.5);
  outline-offset: 2px
}
.btn-025:active {
  transform: scale(.97)
}
HTML
<button class="btn-025">Generate</button>
Prompt

A gradient button whose background is a 300%-wide strip of indigo #6366f1, cyan #06b6d4, purple #a855f7 and back to indigo. On hover the background position slides from 0% to 100% over 600ms so the colours flow across the button. White 15px semibold text, 10px radius, 13px by 26px padding; active scales to 97%. Focus ring translucent indigo.