.wai-referencia .featured-imagebox-portfolio .featured-thumbnail {
  text-align: center;
}

.wai-referencia .featured-imagebox-portfolio .featured-thumbnail img {
  filter: grayscale(100%);
  opacity: 0.75;
}

.wai-referencia .featured-imagebox-portfolio .featured-thumbnail:hover img {
  filter: none;
  opacity: 1;
}