<div class="hover">Hover Me</div>
<div class="pop">
  <p>This is</p>
  <p>PopUp</p>
  <p>with shadow</p>
</div>

body {
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}
.pop {
  background: #fff;
  position: absolute;
  opacity: 0;
  top: 10px;
  box-shadow: 0 0 5px 0 #0003;
  font-size: .9rem;
  font-weight: 100;
  padding: 1rem 3rem;
  border: 1px solid #0003;
  border-radius: .5rem;
  font-family: sans-serif;
  text-align: center;
  line-height: 1.5;
  transition: all .3s ease-in-out;
  color: #000a;
}

.hover {
  border: 1px solid #0003;
  padding: 1rem;
  border-radius: .3rem;
  font-family: sans-serif;
  background: #f88;
  color: #fffe;
}

.hover:hover ~ .pop {
  opacity:1;
}
.hover:hover {
  background: #f55;
  color: #fff;
}