/* AB同框壳：A/B 共用描边 + 角花（Word 蓝） */
.shell-frame{
  pointer-events:none;
  position:fixed;
  inset:12px;
  border:1px solid rgba(24,90,189,.30);
  border-radius:24px;
  box-shadow:
    inset 0 0 0 1px rgba(255,255,255,.55),
    0 22px 60px rgba(24,90,189,.14);
  z-index:2147483000;
}
.shell-flower{
  pointer-events:none;
  position:fixed;
  z-index:2147483001;
  width:72px;height:72px;
  opacity:.5;
  background:
    radial-gradient(circle at 50% 50%, rgba(24,90,189,.30) 0 6px, transparent 7px),
    conic-gradient(from 20deg, rgba(24,90,189,.18), transparent 40%, rgba(24,90,189,.18), transparent 75%, rgba(15,61,130,.12));
  border-radius:50%;
}
.shell-flower.tl{top:28px;left:28px}
.shell-flower.br{bottom:28px;right:28px}
@media (max-width:720px){
  .shell-frame{inset:6px;border-radius:14px}
  .shell-flower{width:48px;height:48px;opacity:.38}
  .shell-flower.tl{top:14px;left:14px}
  .shell-flower.br{bottom:14px;right:14px}
}