#overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(207,209,79,0.8);
  display: flex;
  align-items: center;
  justify-content: center;
}

#overlay img {
  max-width: 80%;
  max-height: 70%;
  opacity: 1;
  transition: opacity 0.5s;
  border-radius: 0;
  border: 20px solid yellow;
}

#gallery img {
  width: 30%;
  height: auto;
  margin: 10px;
  border-radius: 0;
}

#overlay button {
  background-color: #18468a;
  color: #edd362;
  border: none;
  color: white;
  font-size: 24px;
  cursor: pointer;
}

#prev {
  position: absolute;
  left: 10px;
}

#next {
  position: absolute;
  right: 10px;
}

#close {
  position: absolute;
  top: 10px;
  right: 10px;
}