.full_img {
  display: none;
  width: 100%;
  height: 100%;
  position: fixed;
  z-index: 20;
  justify-content: center;
  align-items: center;
}

.backdrop {
  display: none;
  position: fixed;
  z-index: 15;
  width: 100%;
  height: 100%;
  background-color: rgba(255, 255, 255, 80%);
}

.image-items {
  position: fixed;
  z-index: 20;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.main-img {
  width: 100%;
}

.main-img img {
  width: 100%;
  cursor: pointer;
}

#go-back {
  left: 0px;
}

#go-next {
  right: 0px;
}

#go-back , #go-next {
  z-index: 20;
  display: flex;
  justify-content: center;
  align-items: center;
  width: 15%;
  height: 100%;
  cursor: pointer;
  position: fixed;
  background: none;
}

#go-back:hover , #go-back:active, #go-next:hover, #go-next:active {
  background-color: rgba(0, 0, 0, 50%);
  filter: invert(40%);
}

#go-back img {
  transform: rotate(0.5turn);
}

#go-back img, #go-next img {
  width: 60px;
}

.btn--category {
  display: flex;
  position: sticky;
  top: 71px;
  padding: 10px 2.8%;
  margin: 5px;
}

.btn--category div {
  cursor: pointer;
  padding: 5px 10px;
  font-weight: bold;
  background-color: lightgray;
  border: solid 3px aliceblue;
}

.btn--category .active {
  background-color: #5d595b;
  color: white;
  border: solid 3px gray;
}

#gallery {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
}

.gal-img {
  width: 30%;
  margin: 10px;
}

.gal-img img {
  width: 100%;
  cursor: pointer;
  height: auto;
}

.gal-img img:hover {
    border-color: #5d595b;
} 

.open {
  display: flex;
}

@media (max-width: 1060px) {
  .btn--category {
    top: 34px;
  }
}

@media (max-width: 640px) {
    .gal-img {
        width: 100%;
        margin: 5px;
    }
    .btn--category div {
      padding: 10px 5px;
    }
}