/* 演示水印：角落轻量提示，不遮挡表格与表单 */
.site-wm {
  position: fixed;
  inset: auto 12px 10px auto;
  z-index: 5;
  pointer-events: none;
  overflow: visible;
  user-select: none;
  width: min(280px, 42vw);
  height: 28px;
  opacity: 0.28;
}
.site-wm::before {
  content: "18016313342 · 算数科技";
  display: block;
  font: 600 11px/28px "Microsoft YaHei", "PingFang SC", sans-serif;
  color: #4a5a52;
  letter-spacing: .04em;
  text-align: right;
  white-space: nowrap;
}
.screen-body .site-wm {
  opacity: 0.35;
}
.screen-body .site-wm::before {
  color: rgba(220, 230, 240, 0.85);
}
@media print {
  .site-wm { display: none; }
}