.side-by-side {
  display: flex;
  gap: 1rem;
}
.side-by-side > div {
  flex: 1;
}
.preview-box {
  width: 100%;
  max-width: 640px;
  height: 480px;
  background-color: #f0f0f0;
  display: flex;
  justify-content: center;
  align-items: center;
  border-radius: 8px;
  overflow: hidden;
  position: relative;
}
.preview-box img, .preview-box video {
  max-width: 100%;
  max-height: 100%;
  border-radius: 8px;
}
.placeholder-text {
  color: #999;
  font-weight: bold;
}
.d-none {
  display: none !important;
}