@adobe/spectrum-css/dist/components/asset/index.css

The Spectrum CSS top-level backwards compatible package

.spectrum-Asset {
  width: 100%;
  height: 100%;
  display: -ms-flexbox;
  display: flex;
  -ms-flex-align: center;
      align-items: center;
  -ms-flex-pack: center;
      justify-content: center;
}
.spectrum-Asset-image {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  transition: opacity 130ms;
}
.spectrum-Asset-folder,
.spectrum-Asset-file {
  width: 100%;
  height: 100%;
  min-width: 48px;
  max-width: 80px;
  margin: 20px;
}