body{
  background-color:#ecebeb;
}

#mainPage img {
  max-width: 100%;
  max-height: 100%;
  bottom: 0;
  left: 0;
  margin: auto;
  overflow: auto;
  position: fixed;
  right: 0;
  top: 0;
  -o-object-fit: contain;
  object-fit: contain;
  cursor: pointer;
}

.button {
  position: absolute;
  top: 50%;
  left: 50%;
  margin-top: -50px;
  margin-left: -50px;
  display: flex;
  width: 100px;
  height: 100px;
  border: 0;
  border-radius: 50px;
  text-align: center;
  line-height: 100px;
  color: #fff;
  background: rgba(47, 103, 113, 0.85);
  outline: none;
  transition: all 0.15s;
  cursor: pointer;
}
.play-button:hover > div.button {
  background: #2f6771;
  transform: scale(1.1) perspective(1px);

}
.play-button .label {
  left: 0;
  width: 100px;
  font-size: 14px;
  font-weight: 700;
  color: #2f6771;
  opacity: 0;
  transition: opacity 0.3s, transform 0.3s;
  transform: rotateY(180deg);
}

.play-button:focus .label,
.play-button:hover .label {
  opacity: 1;
  transform: rotateY(0);
}

.play-button .fa-play {
  position: absolute;
  top: 0;
  height: 100px;
  line-height: 100px;
}
.play-button .fa-play {
  display: block;
  left: 25px;
  width: 64px;
  font-size: 64px;
}
:first-child {
  margin-top: 0;
}