* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html, body {
  width: 100%;
  height: 100%;
  background: #000;
  overflow: hidden;
}

.page {
  width: 100%;
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}

.photo {
  display: block;
  max-width: 100%;
  max-height: 100vh;
  width: auto;
  height: auto;
  object-fit: contain;
}

/* Download button centered over the lower edge of the image. */
.btn-download {
  position: absolute;
  bottom: 50px;
  left: 50%;
  transform: translateX(-50%);
  background: none;
  border: none;
  padding: 0;
  cursor: pointer;
  width: clamp(60px, 12vw, 90px);
  -webkit-tap-highlight-color: transparent;
  user-select: none;
}

.btn-download__img {
  width: 100%;
  display: block;
}