/* Open-magazine depth. Never transform the folding surfaces owned by PageFlip. */
#physical-book.open-spread .paper::before {
  background: linear-gradient(90deg,rgba(39,31,20,.06),transparent 4%,transparent 75%,rgba(255,255,255,.18) 87%,rgba(73,56,33,.045) 94%,rgba(36,28,19,.20) 99.5%,rgba(22,18,13,.28));
  box-shadow:inset 0 1px 0 #fff9,inset 0 -1px 0 #9a8e7133;
}
#physical-book.open-spread .paper.--right::before {
  background:linear-gradient(90deg,rgba(22,18,13,.25),rgba(53,41,26,.13) 1.5%,rgba(73,56,33,.045) 5%,rgba(255,255,255,.23) 11%,rgba(255,255,255,.07) 19%,transparent 28%,transparent 95%,rgba(39,31,20,.055));
  box-shadow:inset 0 1px 0 #fff9,inset 0 -1px 0 #9a8e7133;
}
#physical-book.open-spread .paper-stack {
  border:0;background:#eee8da;
  border-radius:2px 2px 10px 10px / 2px 2px 4px 4px;
  box-shadow:0 1px 0 #a89e8c,0 2px 0 #fffaf0,0 3px 0 #b8ae9e,0 4px 0 #f8f3e8,0 5px 0 #bcb4a5,0 7px 5px #332a1e28,0 16px 22px -10px #1c211b70;
}
#physical-book.open-spread .paper-stack::before,
#physical-book.open-spread .paper-stack::after {
  content:'';position:absolute;pointer-events:none;top:1px;bottom:-3px;width:50%;height:auto;
  background:repeating-linear-gradient(0deg,#e1dacd 0px,#fcf8ed 1px,#fcf8ed 2px);
  z-index:-1;opacity:1;transform:none;
}
#physical-book.open-spread .paper-stack::before {
  left:-4px;border-radius:3px 0 48% 5px / 3px 0 6px 3px;
  box-shadow:-4px 5px 8px #302b2226;
}
#physical-book.open-spread .paper-stack::after {
  right:-4px;border-radius:0 3px 5px 48% / 0 3px 3px 6px;
  box-shadow:4px 5px 8px #302b2226;
}
/* Reflection remains on ::after and continues to follow the actual turn. */
@media print {#physical-book.open-spread .paper::before {display:none}}

/* Finished magazine: exposed sheets sit outside the left edge of the back cover. */
#physical-book.back-cover-open .paper-stack {
 box-shadow:-1px 2px 0 #e2ddcf,-2px 3px 0 #b9ad96,-3px 4px 0 #fffdf5,-4px 5px 0 #c7bba6,-5px 6px 0 #f7f2e6,-6px 7px 0 #b7ac98,-7px 8px 0 #fffaf0,-8px 9px 0 #c7bba6,-9px 10px 0 #f0eadb,-10px 11px 0 #b8ae9a,-11px 12px 0 #fff9ed,-13px 17px 20px #182f3b4a;
}
#physical-book.back-cover-open .paper-stack::after {
 right:auto;left:-11px;transform:skewY(-40deg);transform-origin:right bottom;
}