.container {
    position: relative;
  }
  
  .image {
    display: block;
    width: 100%;
    height: auto;
  }
  
  .overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background-color: #636869;
    overflow: hidden;
    width: 100%;
    height: 0;
    transition: all 0.5s;
  }
  
  .container:hover .overlay {
    height: 100%;
  }
  
  .text {
    white-space: nowrap; 
    color: white;
    font-size: 20px;
    position: absolute;
    overflow: hidden;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    -ms-transform: translate(-50%, -50%);
  }