@charset "UTF-8";

/* Back to Top
------------------------------------------------------------ */

.back-to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 900;

  width: 72px;
  height: 72px;
  padding: 0;

  border: 1px solid #969696;
  border-radius: 50%;
  background: transparent;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  color: #969696;

  display: flex;
  align-items: center;
  justify-content: center;

  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);

  transition:
    opacity .25s ease,
    visibility .25s ease,
    transform .25s ease;
}

.back-to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

/* 矢印 */
.back-to-top__arrow {
  position: relative;
  display: block;
  width: 22px;
  height: 30px;
}

.back-to-top__arrow::before {
  content: "";
  position: absolute;
  left: 50%;
  top: 4px;
  width: 1px;
  height: 25px;
  background: currentColor;
  transform: translateX(-50%);
}

.back-to-top__arrow::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 4px;
  width: 10px;
  height: 10px;
  border-top: 1px solid currentColor;
  border-left: 1px solid currentColor;
  transform: translateX(-50%) rotate(45deg);
}

.back-to-top:focus-visible {
  outline: 1px solid #969696;
  outline-offset: 4px;
}

/* Mobile */
@media screen and (max-width: 767px) {
  .back-to-top {
    right: 14px;
    bottom: 14px;
    width: 58px;
    height: 58px;
  }

  .back-to-top__arrow {
    width: 18px;
    height: 26px;
  }

  .back-to-top__arrow::before {
    height: 22px;
  }

  .back-to-top__arrow::after {
    width: 9px;
    height: 9px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .back-to-top {
    transition: none;
  }
}