*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
:root {
  --viewerWidth: min(420px, calc(100svw - 60px));
  --viewerHeight: min(640px, calc(95svh - 60px));
 }

 body {
  overscroll-behavior: none;
}

/* ── VERTICAL READER ── */
.vertical-reader {
  height: calc(95svh - 24px);
  display: grid;
  place-items: center;
  font-family: var(--readingFont);
  position: relative;
  background-color: var(--main-reading-bg);
  overscroll-behavior: none;
}

.page-window {
  width: var(--viewerWidth);
  height: var(--viewerHeight);
  margin-top: 1.5rem;
  position: relative;
  overflow: visible;
  overscroll-behavior: none;
}

.showOutline {
 outline: solid 1px;
}

#pageWindow.debug {
  border: solid 1px;
 }

.page-strip {
  height: var(--viewerHeight);
  display: flex;
  flex-direction: row-reverse;
  overscroll-behavior: none;
  scroll-snap-type: x mandatory;
  scrollbar-width: none;
  -ms-overflow-style: none;
}
.pageStrip::-webkit-scrollbar {
  display: none;
}

.page {
  width: var(--viewerWidth);
  height: var(--viewerHeight);
  scroll-snap-align: start;
  flex-shrink: 0;
  contain: strict;
  writing-mode: vertical-rl;
  text-align: justify;
  overscroll-behavior: none;
  display: grid;
  place-items: center;
}

.page-body {
  width: var(--viewerWidth);
  height: var(--viewerHeight);
  writing-mode: vertical-rl;
  text-align: justify;
  overscroll-behavior: none;
}

/* seek bar */
.seek-bar {
  width: calc(100% - 48px);
  margin-left: 24px;
  margin-right: 24px;
  height: 28px;
  border-top: 1px solid currentColor;
  margin-top: 20px;
  display: flex;
  justify-content: space-between;
  flex-shrink: 0;
}

#busyPaginating {
  display: none;
  flex: 1;
  height: 4px;
  border-radius: 2px;
  position: relative;
  opacity: 0.5;
  width: calc(100% - 72px);
}

#busyIndicator {
width: calc(100% - 72px - 7em);
}

#pageTrack {
 flex: 1;
}

#readingPosition {
 accent-color: grey;
 width: 100%;
 direction: rtl;
 opacity: 0.8;
}

.seek-label {
  font-size: var(--smallFont);
  opacity: 0.9;
  white-space: nowrap;
  min-width: 36px;
  text-align: right;
  margin-left: 1em;
}

#page00.showoverflow {
 border: solid 2px red;
}
/*SANDBOX*/

#paginationSandbox {
 writing-mode: vertical-rl;
 text-align:start;
 position: fixed;
 top: 0px;
 left: 0px; 
 width: var(--viewerWidth);
 height: var(--viewerHeight);
 padding: 0;
 box-sizing: border-box;
 visibility: hidden;
 pointer-events: none;
 z-index: -1;
} 

.vpSandbox {
 display: none;
}

.vpBlock {
 display: none;
}

.vpShow {
 display: block;
}