:root {
  --green-dark: #0d3525;
  --green: #176c49;
  --gold: #d5a72e;
  --cream: #f5f0e5;
  --white: #ffffff;
  --shadow: rgba(5, 24, 16, .34);
  --toolbar-h: 76px;
  --status-h: 58px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  min-height: 100%;
  background: linear-gradient(145deg, #071d14, #124b34);
  font-family: Arial, Helvetica, sans-serif;
  overscroll-behavior: none;
}

body {
  min-height: 100dvh;
  padding: 18px;
}

button, a { font: inherit; }

.app-shell {
  width: min(1180px, 100%);
  min-height: calc(100dvh - 36px);
  margin: 0 auto;
  display: grid;
  grid-template-rows: auto minmax(0, 1fr) auto;
  border: 1px solid rgba(255,255,255,.12);
  border-radius: 24px;
  overflow: hidden;
  background:
    radial-gradient(circle at 15% 15%, rgba(213,167,46,.15), transparent 30%),
    linear-gradient(145deg, #0a2a1d, #0f3d2b);
  box-shadow: 0 30px 90px rgba(0,0,0,.4);
}

.toolbar {
  min-height: var(--toolbar-h);
  padding: 14px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  color: var(--white);
  border-bottom: 1px solid rgba(255,255,255,.1);
  background: rgba(4, 22, 15, .78);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  z-index: 20;
}

.brand-block { display: grid; gap: 4px; min-width: 0; }
.eyebrow { color: var(--gold); font-size: 10px; font-weight: 900; letter-spacing: 2px; }
.brand-block strong { font-size: 18px; white-space: nowrap; }

.toolbar-actions,
.zoom-controls {
  display: flex;
  align-items: center;
  gap: 8px;
}

.toolbar-actions button,
.toolbar-actions a {
  min-width: 40px;
  height: 40px;
  padding: 0 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(255,255,255,.16);
  border-radius: 10px;
  background: rgba(255,255,255,.08);
  color: #fff;
  text-decoration: none;
  cursor: pointer;
  transition: background .2s ease, color .2s ease, transform .2s ease;
}

.toolbar-actions button:hover,
.toolbar-actions a:hover {
  background: var(--gold);
  color: var(--green-dark);
  transform: translateY(-2px);
}

#zoomValue {
  min-width: 52px;
  text-align: center;
  color: rgba(255,255,255,.8);
  font-size: 12px;
}

.viewer {
  position: relative;
  min-height: 0;
  padding: 18px 14px;
  display: grid;
  grid-template-columns: 58px minmax(0, 1fr) 58px;
  align-items: center;
  gap: 14px;
  overflow: hidden;
}

.book-stage {
  min-width: 0;
  min-height: 0;
  height: calc(100dvh - var(--toolbar-h) - var(--status-h) - 72px);
  display: flex;
  align-items: center;
  justify-content: center;
  perspective: 2400px;
  overflow: auto;
  scrollbar-width: thin;
  touch-action: pan-y;
}

.book-wrap {
  display: grid;
  place-items: center;
  transform-origin: center;
  transition: transform .24s ease;
}

.book {
  position: relative;
  height: min(calc(100dvh - 230px), 900px);
  max-height: 100%;
  aspect-ratio: 1024 / 1448;
  transform-style: preserve-3d;
  filter: drop-shadow(0 26px 30px rgba(0,0,0,.38));
  user-select: none;
  -webkit-user-select: none;
}

.static-page,
.under-page,
.turning-sheet {
  position: absolute;
  inset: 0;
  border-radius: 4px 12px 12px 4px;
  overflow: hidden;
  background: var(--cream);
}

.static-page { z-index: 3; }
.under-page { z-index: 1; }

.static-page img,
.under-page img,
.sheet-face img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
  user-select: none;
  -webkit-user-drag: none;
  pointer-events: none;
}

.paper-light {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(90deg, rgba(0,0,0,.12), transparent 4%, transparent 90%, rgba(255,255,255,.18)),
    linear-gradient(115deg, transparent 34%, rgba(255,255,255,.18) 49%, transparent 63%);
  opacity: .5;
}

.turning-sheet {
  z-index: 5;
  display: none;
  overflow: visible;
  transform-style: preserve-3d;
  transform-origin: left center;
  will-change: transform;
}

.turning-sheet.is-active { display: block; }

.sheet-face {
  position: absolute;
  inset: 0;
  overflow: hidden;
  border-radius: 4px 12px 12px 4px;
  background: var(--cream);
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
}

.sheet-front { transform: rotateY(0deg); }
.sheet-back {
  transform: rotateY(180deg);
  box-shadow: inset 20px 0 28px rgba(0,0,0,.13);
}

.page-shadow {
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: 0;
}

.page-shadow-front {
  background: linear-gradient(90deg, transparent 48%, rgba(0,0,0,.44) 100%);
}

.page-shadow-back {
  background: linear-gradient(90deg, rgba(0,0,0,.34), transparent 45%);
}

.book.is-turning-next .turning-sheet {
  animation: pageTurnNext .9s cubic-bezier(.16,.72,.18,1) forwards;
}

.book.is-turning-prev .turning-sheet {
  transform-origin: right center;
  animation: pageTurnPrev .9s cubic-bezier(.16,.72,.18,1) forwards;
}

.book.is-turning-next .page-shadow-front,
.book.is-turning-prev .page-shadow-front {
  animation: shadowFront .9s ease forwards;
}

.book.is-turning-next .page-shadow-back,
.book.is-turning-prev .page-shadow-back {
  animation: shadowBack .9s ease forwards;
}

@keyframes pageTurnNext {
  0%   { transform: rotateY(0deg) skewY(0deg); }
  38%  { transform: rotateY(-68deg) skewY(-.7deg); }
  64%  { transform: rotateY(-122deg) skewY(.5deg); }
  100% { transform: rotateY(-180deg) skewY(0deg); }
}

@keyframes pageTurnPrev {
  0%   { transform: rotateY(0deg) skewY(0deg); }
  38%  { transform: rotateY(68deg) skewY(.7deg); }
  64%  { transform: rotateY(122deg) skewY(-.5deg); }
  100% { transform: rotateY(180deg) skewY(0deg); }
}

@keyframes shadowFront {
  0%, 100% { opacity: 0; }
  46% { opacity: .78; }
}

@keyframes shadowBack {
  0%, 100% { opacity: 0; }
  55% { opacity: .62; }
}

.book-spine {
  position: absolute;
  z-index: 8;
  top: 0;
  bottom: 0;
  left: 0;
  width: 16px;
  pointer-events: none;
  border-radius: 4px 0 0 4px;
  background: linear-gradient(90deg, rgba(0,0,0,.22), rgba(255,255,255,.08), transparent);
  mix-blend-mode: multiply;
}

.page-edge {
  position: absolute;
  z-index: 0;
  top: 4px;
  right: -8px;
  bottom: 4px;
  width: 9px;
  border-radius: 0 8px 8px 0;
  background: repeating-linear-gradient(90deg, #ded7c9 0 1px, #f6f1e7 1px 2px);
  transform: translateZ(-4px);
}

.nav-button {
  width: 54px;
  height: 72px;
  border: 1px solid rgba(255,255,255,.16);
  border-radius: 16px;
  background: rgba(255,255,255,.08);
  color: #fff;
  font-size: 44px;
  line-height: 1;
  cursor: pointer;
  transition: .2s ease;
  z-index: 12;
}

.nav-button:hover:not(:disabled) {
  background: var(--gold);
  color: var(--green-dark);
  transform: scale(1.05);
}

.nav-button:disabled { opacity: .25; cursor: default; }

.statusbar {
  min-height: var(--status-h);
  padding: 12px 20px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 20px;
  color: rgba(255,255,255,.72);
  border-top: 1px solid rgba(255,255,255,.1);
  background: rgba(4,22,15,.65);
  font-size: 12px;
  z-index: 20;
}

.progress {
  height: 4px;
  overflow: hidden;
  border-radius: 999px;
  background: rgba(255,255,255,.12);
}

.progress span {
  display: block;
  height: 100%;
  width: 25%;
  border-radius: inherit;
  background: var(--gold);
  transition: width .35s ease;
}

.page-status { color: #fff; font-weight: 800; }
.hint { text-align: right; }

/* Tablet */
@media (max-width: 760px) {
  :root {
    --toolbar-h: 62px;
    --status-h: 48px;
  }

  html, body {
    width: 100%;
    min-height: 100dvh;
  }

  body {
    padding: 0;
    overflow: hidden;
  }

  .app-shell {
    width: 100%;
    height: 100dvh;
    min-height: 100dvh;
    border: 0;
    border-radius: 0;
  }

  .toolbar {
    min-height: var(--toolbar-h);
    padding: max(9px, env(safe-area-inset-top)) 10px 8px;
    gap: 8px;
  }

  .brand-block strong { font-size: 14px; }
  .eyebrow { font-size: 8px; letter-spacing: 1.5px; }

  .toolbar-actions { gap: 5px; }
  .toolbar-actions button,
  .toolbar-actions a {
    min-width: 36px;
    height: 36px;
    padding: 0 9px;
    border-radius: 9px;
  }

  .zoom-controls { display: none; }

  .viewer {
    grid-template-columns: 1fr;
    padding: 6px 6px 2px;
  }

  .book-stage {
    width: 100%;
    height: calc(100dvh - var(--toolbar-h) - var(--status-h) - 8px);
    overflow: hidden;
    padding: 4px 0;
  }

  .book {
    width: auto;
    height: min(calc(100dvh - 128px), calc(100vw * 1.414));
    max-width: calc(100vw - 12px);
  }

  .nav-button {
    position: absolute;
    top: 50%;
    width: 42px;
    height: 64px;
    border-radius: 0;
    border: 0;
    background: rgba(6, 30, 20, .46);
    font-size: 38px;
    transform: translateY(-50%);
    backdrop-filter: blur(5px);
  }

  .nav-button:hover:not(:disabled) {
    transform: translateY(-50%);
  }

  .nav-prev {
    left: 0;
    border-radius: 0 14px 14px 0;
  }

  .nav-next {
    right: 0;
    border-radius: 14px 0 0 14px;
  }

  .statusbar {
    min-height: var(--status-h);
    padding: 8px 12px max(8px, env(safe-area-inset-bottom));
    grid-template-columns: 1fr auto;
    gap: 12px;
  }

  .hint { display: none; }
}

@media (max-width: 420px) {
  .toolbar-actions a span { display: none; }
  .toolbar-actions a { padding: 0 10px; }
  .brand-block strong { font-size: 13px; }
}

/* Csökkentett mozgás */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    scroll-behavior: auto !important;
    transition-duration: .01ms !important;
  }
}