/* One light sheet turn for explicit front-matter turns and native TOC entry.
 * Geometry belongs to the stable book frame; navigation never waits on animation. */
.book-spread{view-transition-name:book-frame}
.book-spread>.book-running-head{view-transition-name:book-heading}
.book-spread>.paper-left{view-transition-name:book-left}
.book-spread>.paper-right{view-transition-name:book-right}
::view-transition-group(book-frame),::view-transition-group(book-heading),
::view-transition-group(book-left),::view-transition-group(book-right){animation-duration:.7s;animation-timing-function:cubic-bezier(.4,0,.2,1)}
::view-transition-old(root),::view-transition-new(root),
::view-transition-old(book-frame),::view-transition-new(book-frame),
::view-transition-old(book-heading),::view-transition-new(book-heading){animation:none;mix-blend-mode:normal}
::view-transition-image-pair(book-left),::view-transition-image-pair(book-right){perspective:1800px;isolation:isolate}
::view-transition-old(book-left),::view-transition-new(book-right){animation:none;mix-blend-mode:normal}
::view-transition-old(book-right){transform-origin:left center;backface-visibility:hidden;animation:alip-sheet-out .7s cubic-bezier(.4,0,.2,1) both;mix-blend-mode:normal}
::view-transition-new(book-left){transform-origin:right center;backface-visibility:hidden;animation:alip-sheet-in .7s cubic-bezier(.4,0,.2,1) both;mix-blend-mode:normal}
@keyframes alip-sheet-out{from{transform:rotateY(0);filter:brightness(1)}50%{filter:brightness(.88)}to{transform:rotateY(-180deg);filter:brightness(1)}}
@keyframes alip-sheet-in{from{transform:rotateY(180deg);filter:brightness(1)}50%{filter:brightness(.88)}to{transform:rotateY(0);filter:brightness(1)}}
@media(prefers-reduced-motion:reduce){::view-transition-group(*),::view-transition-old(*),::view-transition-new(*){animation:none!important}}