/* ========================================
   #page-top（ページトップへ戻るボタン）
   サイト全体のトーン（濃紫×金）に合わせた
   控えめで上品な仕上がり
======================================== */

#page-top {
  position: fixed;
  right: 10px;
  bottom: 10px;
  z-index: 500;
  opacity: 0;
  visibility: hidden;
  transform: translateY(14px);
  transition:
    opacity 0.5s ease,
    transform 0.5s ease,
    visibility 0.5s;
}

#page-top.UpMove {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

#page-top.DownMove {
  opacity: 0;
  visibility: hidden;
  transform: translateY(14px);
}

#page-top a {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 3px;
  width: 58px;
  height: 58px;
  border-radius: 50%;
  background: linear-gradient(160deg, rgba(28, 18, 54, 0.94), rgba(15, 10, 30, 0.97));
  border: 1px solid rgba(199, 169, 107, 0.4);
  box-shadow: 0 8px 20px rgba(14, 8, 21, 0.28);
  text-decoration: none;
  transition:
    border-color 0.35s ease,
    box-shadow 0.35s ease,
    transform 0.35s ease,
    background 0.35s ease;
}

/* 外側にごく細い金の輪を添えて、静かな装飾に
---------------------------------------- */
#page-top a::before {
  content: '';
  position: absolute;
  inset: -6px;
  border-radius: 50%;
  border: 1px solid rgba(199, 169, 107, 0.22);
  opacity: 0;
  transform: scale(0.85);
  transition: opacity 0.35s ease, transform 0.35s ease;
}

#page-top a i {
  font-size: 0.95rem;
  color: #c7a96b;
  transition: transform 0.35s ease;
}

#page-top a span {
  font-family: "Shippori Mincho B1", serif;
  font-size: 0.55rem;
  font-weight: 600;
  letter-spacing: 0.18em;
  color: rgba(255, 255, 255, 0.75);
}

#page-top a:hover {
  border-color: rgba(199, 169, 107, 0.85);
  box-shadow: 0 12px 28px rgba(14, 8, 21, 0.38);
  transform: translateY(-4px);
}

#page-top a:hover::before {
  opacity: 1;
  transform: scale(1);
}

#page-top a:hover i {
  transform: translateY(-2px);
}

#page-top a:hover span {
  color: #fff;
}


/* ========================================
   Responsive
======================================== */

@media (max-width: 820px) {
  #page-top {
    right: 20px;
    bottom: 20px;
  }

  #page-top a {
    width: 50px;
    height: 50px;
  }

  #page-top a i {
    font-size: 0.85rem;
  }

  #page-top a span {
    font-size: 0.5rem;
  }
}

@media (max-width: 480px) {
  #page-top {
    right: 14px;
    bottom: 14px;
  }
}