/* 背景移动 */

:root {
  --ps-tile-size: 160px;           /* 图案平铺单元尺寸（元素互不重叠） */
  --ps-scroll-speed: 30s;          /* 放慢周期，让移动更顺滑 */
  --cursor-dot-size: 50px;         /* 鼠标圆点直径 */
  --cursor-x: -9999px;             /* 初始隐藏 */
  --cursor-y: -9999px;             /* 初始隐藏 */
}

body { position: relative; z-index: 0; }

/* 日间：深灰（非纯黑）; 暗色：浅灰 */
body::before {
  content: '';
  position: fixed;
  /* 用四边定位并向外扩一圈平铺单元 */
  top: calc(-1 * var(--ps-tile-size));
  right: calc(-1 * var(--ps-tile-size));
  bottom: calc(-1 * var(--ps-tile-size));
  left: calc(-1 * var(--ps-tile-size));
  z-index: -2; 
  pointer-events: none;
  opacity: 0.2;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160' viewBox='0 0 160 160'%3E%3Cg fill='none' stroke='%23222222' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Ccircle cx='40' cy='40' r='22'/%3E%3Cpath d='M120 20 L140 56 L100 56 Z'/%3E%3Cpath d='M28 112 L52 136 M52 112 L28 136'/%3E%3Crect x='100' y='104' width='36' height='36' rx='5' ry='5'/%3E%3C/g%3E%3C/svg%3E");
  background-size: var(--ps-tile-size) var(--ps-tile-size);
  background-repeat: repeat;
  background-position: 0 0;
  transform: translate3d(0, 0, 0);
  will-change: transform;
  animation: ps-bg-pan var(--ps-scroll-speed) linear infinite !important;
  animation-play-state: running !important;
}

.dark-theme body::before,
[data-theme="dark"] body::before {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160' viewBox='0 0 160 160'%3E%3Cg fill='none' stroke='%23cfcfcf' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Ccircle cx='40' cy='40' r='22'/%3E%3Cpath d='M120 20 L140 56 L100 56 Z'/%3E%3Cpath d='M28 112 L52 136 M52 112 L28 136'/%3E%3Crect x='100' y='104' width='36' height='36' rx='5' ry='5'/%3E%3C/g%3E%3C/svg%3E");
  opacity: 0.14;
}

@keyframes ps-bg-pan {
  0%   { transform: translate3d(0, 0, 0); }
  100% { transform: translate3d(-160px, -160px, 0); }
}

@media (prefers-reduced-motion: reduce) {
  body::before {
    animation: ps-bg-pan calc(var(--ps-scroll-speed) * 1.5) linear infinite !important;
    animation-iteration-count: infinite !important;
    animation-play-state: running !important;
  }
}

#cursor-dot {
  position: fixed;
  top: 0; left: 0;
  width: var(--cursor-dot-size);
  height: var(--cursor-dot-size);
  border-radius: 50%;
  background-color: rgba(0, 0, 0, 0.16);
  transform: translate3d(-9999px, -9999px, 0);
  z-index: -1;
  pointer-events: none;
  will-change: transform;
}

.dark-theme #cursor-dot,
[data-theme="dark"] #cursor-dot {
  background-color: rgba(255, 255, 255, 0.24);
}

/* 移动端禁用鼠标圆点（触摸设备/无悬停设备） */
@media (pointer: coarse), (hover: none) {
  #cursor-dot { display: none !important; }
}