/* ==========================================================================
      9) BACKGROUNDS — SLIDE 1 (fumée)
      ========================================================================== */
      .stancreation-hero-background {
        position: fixed;
        inset: 0;
        pointer-events: none;
        z-index: 0;
      
        transform: translate3d(var(--tx, 0px), var(--ty, 0px), 0) rotate(var(--rot, 0deg));
        opacity: 1;
        transition: transform 0.5s ease-out, opacity 0.5s ease;
      }
      
      body.stancreation-hero-background {
        opacity: 1;
        visibility: hidden;
      }
      
      .stancreation-smoke-layer {
        position: absolute;
        width: 100%;
        height: 200%;
        top: -20%;
        left: -20%;
      
        filter: blur(50px);
        opacity: 1;
        mix-blend-mode: multiply;
      
        background: radial-gradient(ellipse at center,
            rgba(255, 255, 255, 0.0) 0%,
            rgba(255, 255, 255, 0.0) 18%,
            rgba(0, 0, 0, 0.15) 36%,
            rgba(0, 0, 0, 0.05) 52%,
            rgba(0, 0, 0, 0.20) 70%,
            rgba(0, 0, 0, 0.38) 85%,
            rgba(0, 0, 0, 0.0) 100%);
      }
      
      .smoke-layer-1 {
        animation: stancreation-smoke-drift-1 10s ease-in-out infinite alternate;
      }
      
      .smoke-layer-2 {
        animation: stancreation-smoke-drift-2 7s ease-in-out infinite alternate;
        opacity: .7;
      }
      
      .smoke-layer-3 {
        animation: stancreation-smoke-drift-3 9s ease-in-out infinite alternate;
        opacity: .55;
      }
      
      @keyframes stancreation-smoke-drift-1 {
        0% {
          transform: scaleX(2.1) scaleY(1.3) rotate(0deg) translate3d(0%, 0%, 0);
        }
      
        50% {
          transform: scaleX(2.4) scaleY(1.2) rotate(8deg) translate3d(4%, -3%, 0);
        }
      
        100% {
          transform: scaleX(2.0) scaleY(1.4) rotate(-6deg) translate3d(-3%, 3%, 0);
        }
      }
      
      @keyframes stancreation-smoke-drift-2 {
        0% {
          transform: scaleX(2.0) scaleY(1.6) rotate(18deg) translate3d(-3%, 2%, 0);
        }
      
        50% {
          transform: scaleX(2.3) scaleY(1.4) rotate(26deg) translate3d(5%, -4%, 0);
        }
      
        100% {
          transform: scaleX(1.9) scaleY(1.7) rotate(10deg) translate3d(-4%, 4%, 0);
        }
      }
      
      @keyframes stancreation-smoke-drift-3 {
        0% {
          transform: scaleX(2.4) scaleY(1.2) rotate(-16deg) translate3d(2%, -2%, 0);
        }
      
        50% {
          transform: scaleX(2.0) scaleY(1.4) rotate(-8deg) translate3d(-3%, 3%, 0);
        }
      
        100% {
          transform: scaleX(2.6) scaleY(1.1) rotate(-22deg) translate3d(4%, 0%, 0);
        }
      }
      
      @media (max-width: 900px) {
        .stancreation-smoke-layer {
          filter: blur(30px);
        }
      }