<button class="btn">
  <span class="description">
    Liquid 
  </span>
  <div class="ocean"></div>
</button>

:root {
  
  --dark-gray: #0C0E12;
  --ocean: #1455C2;
  --light: #fff;
}

body {
  
  width: 100vw;
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--dark-gray);
}

.btn {
  
  background: var(--ocean);
  position: relative;
  font-family: 'Raleway', sans-serif;
  outline: none;
  cursor: pointer;
  border: 0;
  padding: 20px 100px 20px 100px;
  border-radius: 11px;
  font-size: 24px;
  overflow: hidden;
  color: var(--light);
  letter-spacing: 8px;
}

.description {
  
  z-index: 2;
  position: relative;
}

.ocean {
  
  position: absolute;
  left: 0;
  top: -100px;
  width: 100%;
  height: 250px;
  transition: 0.5s;
}

.ocean:before, .ocean:after {
  
  content: '';
  position: absolute;
  width: 150%;
  height: 200%;
  top: 0;
  left: 50%;
  transform: translate(-50%, -85%);
}

.ocean:before {
  
  border-radius: 45%;
  background: rgba(20,20,20,1);
  animation: moveOcean 5s linear infinite;
}

.ocean:after {
  
  border-radius: 40%;
  background: rgba(20,20,20,0.5);
  animation: moveOcean 10s linear infinite;
}

@keyframes moveOcean {
  
  0%{
   transform: translate(-50%, -75%) rotate(0deg);
  }
  100%{
   transform: translate(-50%, -75%) rotate(360deg);
  }
}