forgejo/web_src/css/modules/dimmer.css

body:has(> .ui.active.dimmer) {
  overflow: hidden;
}

.ui.dimmer {
  align-items: center;
  animation-fill-mode: both;
  background: var(--color-overlay-backdrop);
  display: none;
  flex-direction: column;
  height: 100%;
  position: fixed;
  opacity: 0;
  overflow: hidden auto;
  transform-origin: center center;
  justify-content: center;
  user-select: none;
  width: 100%;
  will-change: opacity;
  z-index: 1000;

  &.active {
    display: flex;
    opacity: 1;
  }

  .scrolling {
    top: 1em;
  }
}