<div class="container">
  <div class="inner"> <span>i</span>
    <h1>Hi！</h1>
    <p>我这里是气泡提示的内容</p>
  </div>
</div>

 
body {
  background: #DCF5FF;
  margin: 0;
  height: 100vh;
  display: grid;
  justify-items: center;
  align-items: center;
  font-family: 'Nunito', 'sans-serif';
}
 
.inner {
  background: #e8c827;
  padding: 1em;
  border-radius: 10px;
  width: 250px;
  clip-path: circle(10% at 90% 20%);
  transition: all .5s ease-in-out;
  cursor: pointer;
}
.inner:hover {
  clip-path: circle(75%);
  background: #00B6FF;
}
.inner h1 {
  color: white;
  margin: 0;
}
.inner p {
  color: white;
  font-size: .8rem;
}
.inner span {
  float: right;
  color: white;
  font-weight: bold;
  transition: color .5s;
  position: relative;
  margin-right: 4%;
  line-height:12px;
  font-size:24px;
}
.inner:hover span {
  color: rgba(255, 255, 255, 0);
}