Gradient icon

.card-064 {
  display: block;
  width: 270px;
  padding: 24px;
  background: #0b0b0f;
  border: 1px solid #1f1f28;
  border-radius: 18px;
  text-decoration: none;
  font-family: system-ui,sans-serif;
  color: #f4f4f5;
  transition: border-color .2s,background .2s
}
.card-064:hover {
  border-color: #3b3b4a;
  background: #101018
}
.card-064__icon {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  margin-bottom: 18px;
  border-radius: 12px;
  background: linear-gradient(135deg,#f472b6,#8b5cf6);
  color: #fff;
  box-shadow: 0 8px 20px -6px rgba(139,92,246,.6)
}
.card-064 h3 {
  margin: 0 0 6px;
  font-size: 17px
}
.card-064 p {
  margin: 0 0 16px;
  font-size: 13.5px;
  line-height: 1.55;
  color: #a1a1aa
}
.card-064__arrow {
  font-size: 13px;
  font-weight: 600;
  color: #c4b5fd;
  transition: letter-spacing .2s
}
.card-064:hover .card-064__arrow {
  letter-spacing: .04em
}
.card-064 :is(a,button,input,select,textarea):focus-visible { outline: 2px solid currentColor; outline-offset: 2px; }

<a class="card-064" href="#">
  <span class="card-064__icon"><svg viewBox="0 0 24 24" width="20" height="20" fill="none" stroke="currentColor" stroke-width="2"><rect x="3" y="3" width="18" height="18" rx="3"/><path d="M3 9h18M9 21V9"/></svg></span>
  <h3>Layout primitives</h3>
  <p>Stack, cluster, sidebar and grid. Compose pages without writing media queries.</p>
  <span class="card-064__arrow">Explore</span>
</a>