/* ═══ SCROLL-TOP.CSS ═══
   Bouton flottant "Revenir en haut" — mobile-first, RGAA, DA PDR·CL
   Source unique pour toutes les pages.
   Position : bas-GAUCHE (dissocié des floating-actions en bas-droite).
*/
.scroll-top{
  position:fixed;
  bottom:20px;
  left:20px;
  width:44px;
  height:44px;
  min-width:44px;
  min-height:44px;
  background:var(--accent,#DC2626);
  color:#fff;
  border:none;
  border-radius:50%;
  cursor:pointer;
  display:flex;
  align-items:center;
  justify-content:center;
  z-index:85;
  opacity:0;
  visibility:hidden;
  transform:translateY(20px);
  transition:opacity 0.3s ease,transform 0.3s ease,visibility 0.3s ease,background 0.2s ease;
  box-shadow:0 4px 12px rgba(0,0,0,0.15);
  -webkit-tap-highlight-color:transparent;
}
.scroll-top.is-visible{
  opacity:1;
  visibility:visible;
  transform:translateY(0);
}
.scroll-top:hover{
  background:var(--accent-dark,#B91C1C);
  transform:translateY(-2px);
  box-shadow:0 6px 16px rgba(220,38,38,0.3);
}
.scroll-top:focus-visible{
  outline:2px solid var(--accent,#DC2626);
  outline-offset:4px;
}
.scroll-top:active{
  transform:translateY(0);
}
@media(min-width:880px){
  .scroll-top{
    bottom:24px;
    left:24px;
    width:48px;
    height:48px;
  }
}
@media(prefers-reduced-motion:reduce){
  .scroll-top{
    transition:opacity 0.1s ease;
    transform:none !important;
  }
  .scroll-top:hover{
    transform:none !important;
  }
}