html, body {
  background: url('https://static.tildacdn.com/tild3934-3661-4761-b262-6631f9653264/gory-temno.jpg') no-repeat center center fixed;
  background-size: cover !important;
}

/* Убираем белый фон у всех стандартных контейнеров */
.t-container,
.t-col,
.t-section,
.t-section__container,
.t396__artboard,
.t396__carrier,
.t-body,
.t-rec,
.t-records,
.t-records .r,
.t-records .t-container,
.t-records .t-section,
.tn-atom,
.t-bgimg,
body [style*="background-color: #ffffff"],
body [style*="background-color: white"],
body [style*="background:#fff"],
body [style*="background:white"] {
  background: transparent !important;
}