:root {
  --block-title-color-bk-bg:rgb(252, 252, 255);
  }

/*--↓↓gotop按鈕↓↓ --*/
#go_top_embed{
  height:0; right:0; bottom:0;
   position:sticky;
  z-index:99; 
  /*opacity:0;  
  transition:opacity 0.3s, visibility 0.3s; */
  display: none;
  pointer-events: initial;
}

#go_top_embed .go_top{
  width: clamp(40px,5vw,55px);
  height: clamp(40px,5vw,55px);
  position: absolute;  
  transition: transform 0.3s ease, filter 0.3s ease; /* 平滑過渡效果 */
  bottom: 0;
  right: 0;
  z-index: 999999;
  transform: translateX(-1rem) translateY(-1rem);
  background-color: #404040;
  border: 1px solid #999999;
  background: linear-gradient(to bottom,  rgba(43,43,43,0.8) 0%,rgba(43,43,43,0.6) 100%);
}
#go_top_embed .go_top a{
  width: 100%; height: 100%; display: block; cursor: pointer;
  display: flex; justify-content: center; align-items: center;
 }
 #go_top_embed .go_top a svg {
  width: 70%; 
  height: 70%;
  mask-image: url(../images/gotop.svg);
  mask-repeat: no-repeat;
  background-color: var(--block-title-color-bk-bg);
  -webkit-mask-image:url(../images/gotop.svg);
  -webkit-mask-repeat:no-repeat;
}
#go_top_embed:hover{
  filter: brightness(1.2); /* 提升亮度到 120% */
}
/*
#go_top_embed.visible {
  opacity: 1;
  pointer-events: initial;
}*/