* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html, body {
  width: 100%;
  min-height: 100%;
  font-family: Arial, Helvetica, sans-serif;
}

body {
  min-height: 100vh;
  background-image: url("background.jpg");
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  overflow-x: hidden;
}

.site-header {
  width: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 18px 16px 0;
}

.logo-link {
  display: inline-block;
  line-height: 0;
}

.header-logo {
  width: min(720px, 92vw);
  max-width: 100%;
  height: auto;
  display: block;
  filter: drop-shadow(0 0 18px rgba(0, 0, 0, 0.55));
}

.page {
  width: 100%;
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px 16px;
}

.model-wrap {
  width: min(1100px, 96vw);
  height: min(72vh, 820px);
  min-height: 420px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: visible;
}

.model-perspective {
  perspective: 1400px;
  perspective-origin: center center;
  display: flex;
  align-items: center;
  justify-content: center;
  width: min(84vw, 620px);
  height: min(84vw, 620px);
  max-width: 620px;
  max-height: 620px;
  min-width: 320px;
  min-height: 320px;
}

.hero-model {
  width: 100%;
  height: 100%;
  --progress-bar-color: transparent;
  background: transparent;
  transform-style: preserve-3d;
  transform-origin: center center;
  will-change: transform;
  animation: hts-tumble 6s linear infinite;
}

@keyframes hts-tumble {
  0% {
    transform: scale(1.45) rotateX(0deg) rotateY(0deg) rotateZ(0deg);
  }
  25% {
    transform: scale(1.45) rotateX(90deg) rotateY(120deg) rotateZ(45deg);
  }
  50% {
    transform: scale(1.45) rotateX(180deg) rotateY(240deg) rotateZ(180deg);
  }
  75% {
    transform: scale(1.45) rotateX(270deg) rotateY(300deg) rotateZ(300deg);
  }
  100% {
    transform: scale(1.45) rotateX(360deg) rotateY(360deg) rotateZ(360deg);
  }
}

.footer {
  width: 100%;
  text-align: center;
  color: white;
  font-size: 14px;
  padding: 18px 12px 22px;
  background: rgba(0, 0, 0, 0.35);
  text-shadow: 0 1px 3px rgba(0, 0, 0, 0.85);
}

@media (max-width: 768px) {
  .site-header {
    padding-top: 12px;
  }

  .header-logo {
    width: min(96vw, 820px);
  }

  .model-wrap {
    width: min(96vw, 620px);
    height: min(56vh, 520px);
    min-height: 320px;
  }

  .model-perspective {
    width: min(82vw, 420px);
    height: min(82vw, 420px);
    min-width: 240px;
    min-height: 240px;
  }

  .hero-model {
    animation: hts-tumble-mobile 6s linear infinite;
  }

  @keyframes hts-tumble-mobile {
    0% {
      transform: scale(1.28) rotateX(0deg) rotateY(0deg) rotateZ(0deg);
    }
    25% {
      transform: scale(1.28) rotateX(90deg) rotateY(120deg) rotateZ(45deg);
    }
    50% {
      transform: scale(1.28) rotateX(180deg) rotateY(240deg) rotateZ(180deg);
    }
    75% {
      transform: scale(1.28) rotateX(270deg) rotateY(300deg) rotateZ(300deg);
    }
    100% {
      transform: scale(1.28) rotateX(360deg) rotateY(360deg) rotateZ(360deg);
    }
  }

  .footer {
    font-size: 13px;
    padding-bottom: 18px;
  }
}