.abertura img {
  max-width: 100%;
  height: 420px;
  max-height: 45vh;
}

h1 {
  width: 6.5em;
}

.float-esquerda {
  width: 280px;
  margin-top: 30px;
}

@media (max-width: 991.98px) {
  .intro {
    padding-top: 20px;
  }
  .abertura {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    margin-bottom: 40px;
  }
  .abertura img {  ;
    max-width: 100%;
    height: auto;
    max-height: 30vh;
  }
  h1 {
    text-align: center;
    margin-left: 0;
    width: 8em;
    max-width: 80vw;
    margin-top: 1rem;
  }
}
@media (max-width: 767.98px) {
  .float-esquerda {
    width: 300px;
  	max-width: 80%;
  }

}
@media (max-width: 575.98px) {

}