#galeria {
  position: relative;
  padding: 20px 0;
  width: 100%;
  margin: 0;
}

#gallery {
  position: relative;
  visibility: visible;
  width: 100%;
  padding: 10px;
}

.gallery-item {
  position: relative;
  float: left;
}

@media (max-width: 991px) {
  .gallery-item {
    width: 31%;  
  }
}

@media (min-width: 992px) {
  .gallery-item {
    width: 19.6%;  
  }
}

.gallery-item img {
  display: block;
  width: 100%;
  filter: gray; /* IE6-9 */
  -webkit-filter: grayscale(1); /* Google Chrome, Safari 6+ & Opera 15+ */
}

.gallery-item img:hover {
  filter: none; /* IE6-9 */
  -webkit-filter: grayscale(0); /* Google Chrome, Safari 6+ & Opera 15+ */
}

#btngallery {
  margin: 5px;
}