body{

    background-attachment: fixed;
}


/* Composants "verre" génériques (réutilisables) */
.glass{
  background: var(--glass);
  backdrop-filter: blur(var(--blur));
  -webkit-backdrop-filter: blur(var(--blur));
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
}
.glow{
  position: relative;
}
.glow::before{
  content: "";
  position: absolute; inset: -1px; pointer-events: none;
  border-radius: calc(var(--radius) + 1px);
  background: linear-gradient(135deg, rgba(39,240,208,.65), rgba(0,191,166,0) 40%, rgba(159,255,227,.5) 70%, rgba(39,240,208,0) 100%);
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor; mask-composite: exclude;
  padding: 1px;
}

/* === Bouton Retour === */
.btn-back{
  --h: 46px;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  height: var(--h);
  padding: 0 16px 0 14px;
  
  cursor: pointer;
  border: none;
  outline: none;
  position: relative;
  overflow: hidden;
  isolation: isolate;
  transition: transform .12s ease, box-shadow .2s ease, background-color .25s ease;
}

/* Halo animé doux au survol */
.btn-back__bg{
  position: absolute; inset: -40%;
  background:
    radial-gradient(120px 120px at 10% 50%, rgba(39,240,208,.28), transparent 60%),
    radial-gradient(160px 160px at 80% 50%, rgba(159,255,227,.22), transparent 60%);
  transform: scale(0.9);
  opacity: .6;
  transition: transform .35s ease, opacity .35s ease;
  z-index: -1;
}

/* Icône + label */
.btn-back__icon{
  display: inline-grid; place-items: center;
  width: 32px; height: 32px;
  border-radius: 10px;
  background: linear-gradient(135deg, rgba(39,240,208,.18), rgba(0,191,166,.10));
  border: 1px solid rgba(159,255,227,.35);
  transition: transform .2s ease;
}
.btn-back__label{
  font-weight: 700; letter-spacing: .2px;
}

/* Interactions */
.btn-back:hover{
  transform: translateY(-1px);
  box-shadow: 0 10px 28px rgba(0,0,0,.25);
}
.btn-back:hover .btn-back__bg{
  transform: scale(1);
  opacity: .9;
}
.btn-back:active{
  transform: translateY(0);
}
.btn-back:focus-visible{
  outline: 2px solid #27F0D0; outline-offset: 3px;
  border-radius: calc(var(--radius) + 2px);
}

/* Animation “retour” subtile de l’icône au hover */
.btn-back:hover .btn-back__icon{
  transform: translateX(-2px);
}

/* Variante fixe (si tu veux un bouton toujours visible en bas à gauche) */
.btn-back--fixed{
  position: fixed; left: 14px; bottom: 14px; z-index: 9999;
}

/* Support RTL : inverser la direction (si <html dir="rtl">) */
html[dir="rtl"] .btn-back{
  flex-direction: row-reverse;
  padding: 0 14px 0 16px;
}
html[dir="rtl"] .btn-back:hover .btn-back__icon{
  transform: translateX(2px);
}