Creating a Bonvoy aesthetic vector art background involves using a combination of CSS and SVG. Here's a brief snippet to get you started:

.background {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100vh;
  background-image: url('bonvoy-icon.svg');
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
}

/* Optional: add some animation */
.background {
  animation: scale 10s infinite linear;
}

@keyframes scale {
  0% {
    transform: scale(1);
  }
  100% {
    transform: scale(2);
  }
}

In this example, replace 'bonvoy-icon.svg' with the actual SVG file containing your Bonvoy aesthetic vector art. You can then use this class to apply the background to any element on your page.

Note that you'll need to create or obtain an SVG file that matches the desired Bonvoy aesthetic. You can find inspiration online or create your own using a tool like Adobe Illustrator or Inkscape.