:root {
  color-scheme: dark;
  background: #111;
}

* { box-sizing: border-box; }

html, body, #player {
  width: 100%;
  min-width: 100%;
  height: 100%;
  min-height: 100%;
  margin: 0;
  overflow: hidden;
}

#player { position: relative; background: #111; }

.page-frame {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
  opacity: 0;
  pointer-events: none;
  transition: opacity 800ms ease-in-out;
}

.page-frame.is-visible {
  opacity: 1;
  pointer-events: auto;
}

.empty-message {
  display: grid;
  place-items: center;
  width: 100%;
  height: 100%;
  margin: 0;
  color: #ddd;
  font: 600 2rem system-ui, sans-serif;
}