/* 仅放动画与特效相关样式，便于维护 */

/* 全屏雪花画布（顶层、不影响交互） */
#snow-canvas{
  position:fixed;
  inset:0;
  width:100%;
  height:100%;
  pointer-events:none;
  z-index:100001;
}

/* 返回顶部悬浮按钮 */
#tbox{
  position:fixed;
  right:18px;
  bottom:18px;
  z-index:100002;
  display:flex;
  flex-direction:column;
  gap:10px;
}
#gotop{
  width:44px;
  height:44px;
  border-radius:12px;
  border:1px solid rgba(255,255,255,0.45);
  background:rgba(15,23,42,0.30);
  backdrop-filter: blur(6px);
  display:flex;
  align-items:center;
  justify-content:center;
  color:#fff;
  cursor:pointer;
  box-shadow:0 14px 28px rgba(0,0,0,0.18);
  opacity:0;
  transform:translateY(6px);
  pointer-events:none;
  transition:opacity .18s ease, transform .18s ease, background .18s ease;
}
#gotop.is-visible{
  opacity:1;
  transform:translateY(0);
  pointer-events:auto;
}
#gotop:hover{background:rgba(15,23,42,0.42);}

/* 导航 hover 细节 */
nav.site-nav a{
  transition: transform .15s ease, background .15s ease, box-shadow .15s ease;
}
nav.site-nav a:hover{ transform: translateY(-1px); }

/* 图片与卡片的 hover 轻动效 */
.arrow_box, .sidebox, figure.hero-figure, .about-card{
  will-change: transform;
}