/* Sito-Film scroll-intro v1.0 - struttura minima. Lo stile del brand va nel tema/pagina. */
.sf-film{position:relative;height:calc(var(--sf-length,300) * 1vh);background:var(--sf-bg,#000);
  --sf-seam:#000}
.sf-stage{position:sticky;top:0;height:100vh;height:100svh;overflow:hidden;contain:paint}
.sf-canvas{position:absolute;inset:0;width:100%;height:100%;display:block;z-index:0}
.sf-beat{position:absolute;z-index:3;opacity:0;visibility:hidden;will-change:opacity,transform;
  pointer-events:none}
.sf-beat a,.sf-beat button{pointer-events:auto}
.sf-fade{position:absolute;inset:0;z-index:1;background:var(--sf-seam);opacity:0;pointer-events:none}
/* barra di caricamento discreta: sparisce a film caricato */
.sf-film::after{content:"";position:absolute;left:0;top:0;height:2px;z-index:4;
  width:calc(var(--sf-loaded,0) * 100%);background:currentColor;opacity:.5;
  transition:opacity .6s}
.sf-film.sf-loaded::after{opacity:0}
/* prima del primo frame: niente flash bianco */
.sf-film:not(.sf-ready) .sf-canvas{opacity:0}
.sf-canvas{transition:opacity .4s}
/* movimento ridotto: una schermata, primo frame fermo, solo il beat d'apertura */
.sf-film.sf-reduced{height:100vh;height:100svh}
@media (prefers-reduced-motion: reduce){.sf-beat{transition:none}}