body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  background-image: url("../img/IGC2_top.jpg");
  background-size: cover;
  background-position: top center;
  background-repeat: no-repeat;
  pointer-events: none;
  opacity: 0;
  transition: opacity 1s ease-in-out;
}

body.loaded::before {
  opacity: 1;
}

header {
  opacity: 0;
  transition: opacity 1s ease-in-out;
}

header.loaded {
  opacity: 1;
}

.footer-wrapper {
  position: fixed;
  bottom: 20px;
  left: 0;
  width: 100%;
  padding: 0 20px;
  box-sizing: border-box;

  display: flex;
  align-items: flex-end;
  justify-content: space-between;

  z-index: 1;
  pointer-events: none;
}

.footer-text {
  font-family: Impact, sans-serif;
  font-size: clamp(16px, 10vw, 100px);
  font-weight: bold;
  color: #fff;
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
  letter-spacing: 0.02em;
  text-align: left;
  line-height: 0.95;
  flex-shrink: 0;
  letter-spacing: 0.07em;
}

.footer-text .igc {
  display: block;
  font-size: 0.9em;
}

.sub-text {
  color: #fff;
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
  font-size: clamp(12px, 2vw, 48px);
  opacity: 0.95;
  white-space: nowrap;

  transform: translateY(-10%);

  text-align: right;
  margin-left: 0;
}

@media (max-height: 700px) {
  body {
    background-size: auto 100%;
    background-position: top center;
  }

  .footer-wrapper {
    bottom: 10px;
    padding: 0 10px;
  }
  .footer-text {
    font-size: clamp(12px, 8vw, 80px);
  }
}

@media (max-width: 480px) {
  .footer-wrapper {
    padding: 0 10px;
  }

  .sub-text {
    font-size: clamp(8px, 2vw, 12px);
    transform: translateY(-4%);
  }
}

/* フェードイン効果 */
main.fade-in {
  opacity: 0;
  transition: opacity 1s ease-in-out;
}

main.fade-in.loaded {
  opacity: 1;
}