@media only screen and (max-width: 600px) and (min-width: 200px) {
  .banner {
    background: url('../images/derma.jpg') 80% 50%;
    height: 100%;
    position: relative;
    background-size: cover;
    padding: 0px 0px;
  }
  .ptb40 {
    padding-top: 20px;
    padding-bottom: 20px;
  }
  .heading h3 {
    font-size: 2rem;
    color: #1b1b1b;
  }
  .client-flex img {
    max-width: 100px;
    height: auto;
    width: 100%;
  }
  .footer span {
    text-align: center;
  }
}