.photo-gallery {
  width: 80%;
  margin: 100px auto 50px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  grid-gap: 20px;
}

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

.photo-gallery img:hover {
  transform: scale(1.1);
}

.full-img {
  width: 100%;
  height: 100vh;
  background: rgba(0,0,0,0.9);
  position: fixed;
  top: 0;
  left: 0;
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 100;
}

.full-img img {
  width: 90%;
  max-width: 500px;
}

.full-img span {
  position: absolute;
  top: 5%;
  right: 5%;
  font-size: 30px;
  color: #fff;
  cursor: pointer;
}