* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: "Inter", sans-serif;
  background: #0c0e14;
  color: #e4e4ed;
  min-height: 100vh;
}

/* ── Topbar ── */
.topbar {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  padding: 1rem 2rem;
  background: #13151d;
  border-bottom: 1px solid #22252f;
}
.topbar h1 { font-size: 1.05rem; font-weight: 600; }
.tag {
  font-size: 0.68rem; font-weight: 600; text-transform: uppercase;
  padding: 0.18rem 0.5rem; border-radius: 4px;
  background: #4f6ef7; color: #fff; letter-spacing: 0.6px;
}

/* ── Main ── */
.main {
  max-width: 960px;
  margin: 2rem auto;
  padding: 0 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  padding-bottom: 4rem;
}

.card {
  background: #16181f;
  border: 1px solid #23262f;
  border-radius: 14px;
  padding: 1.6rem;
}
.card h2 { font-size: 1.1rem; font-weight: 600; margin-bottom: 0.3rem; }
.card p { color: #9499a8; font-size: 0.88rem; margin-bottom: 1rem; }
.card-head { display: flex; align-items: center; gap: 1rem; margin-bottom: 0.3rem; flex-wrap: wrap; }
.card-head h2 { margin-bottom: 0; }

/* ── Buttons ── */
.btn {
  border: none; border-radius: 8px;
  padding: 0.6rem 1.1rem; font: inherit; font-size: 0.86rem; font-weight: 500;
  cursor: pointer; transition: background 120ms, transform 100ms;
}
.btn:active { transform: scale(0.97); }
.btn.primary { background: #4f6ef7; color: #fff; }
.btn.primary:hover { background: #6480ff; }
.btn.ghost {
  background: rgba(255,255,255,0.06); color: #bbb;
  border: 1px solid rgba(255,255,255,0.1);
}
.btn.ghost:hover { background: rgba(255,255,255,0.12); }
.btn.sm { padding: 0.4rem 0.75rem; font-size: 0.8rem; }

/* ── Drop zone ── */
.drop-zone {
  display: block; cursor: pointer;
  border: 2px dashed #2e313c; border-radius: 14px;
  padding: 2.4rem 1rem; text-align: center;
  transition: border-color 160ms, background 160ms;
}
.drop-zone:hover, .drop-zone.over {
  border-color: #4f6ef7; background: rgba(79,110,247,0.06);
}
.drop-zone input { display: none; }
.drop-zone-inner { display: flex; flex-direction: column; align-items: center; gap: 0.4rem; color: #777; }
.drop-zone-inner strong { color: #ccc; font-size: 0.95rem; }
.drop-zone-inner span { font-size: 0.8rem; }
.drop-zone-inner svg { color: #4f6ef7; margin-bottom: 0.3rem; }

/* ── Pages grid ── */
.pages-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: 0.8rem;
}

.page-card {
  position: relative; background: #1c1e28;
  border: 1px solid #2a2d38; border-radius: 10px;
  overflow: hidden; cursor: grab;
  transition: box-shadow 150ms, transform 100ms;
}
.page-card:hover { box-shadow: 0 4px 18px rgba(79,110,247,0.15); transform: translateY(-2px); }
.page-card.dragging { opacity: 0.4; transform: scale(0.92); }
.page-card.drag-over { border-color: #4f6ef7; box-shadow: 0 0 0 2px #4f6ef7; }

.page-card img {
  width: 100%; aspect-ratio: 16/10; object-fit: cover; display: block;
  user-select: none; pointer-events: none;
}
.page-card .badge {
  position: absolute; top: 6px; left: 6px;
  background: rgba(0,0,0,0.65); color: #fff;
  font-size: 0.68rem; font-weight: 600; padding: 0.15rem 0.45rem;
  border-radius: 4px;
}
.page-card .remove-btn {
  position: absolute; top: 4px; right: 4px;
  width: 24px; height: 24px; border-radius: 50%;
  background: rgba(214,60,60,0.85); color: #fff;
  border: none; font-size: 0.85rem; cursor: pointer;
  display: grid; place-content: center;
  opacity: 0; transition: opacity 120ms;
}
.page-card:hover .remove-btn { opacity: 1; }

/* ── Generate ── */
.gen-row { display: flex; gap: 0.8rem; align-items: flex-end; flex-wrap: wrap; }
.field { display: flex; flex-direction: column; gap: 0.3rem; flex: 1; min-width: 200px; }
.field span { font-size: 0.78rem; color: #888; }
.field input[type="text"] {
  background: #1c1e28; border: 1px solid #2e313c; color: #e4e4ed;
  padding: 0.55rem 0.8rem; border-radius: 8px; font: inherit; font-size: 0.9rem;
}
.field input:focus { outline: none; border-color: #4f6ef7; }

.progress-bar {
  height: 6px; background: #23262f; border-radius: 4px;
  margin-top: 1rem; overflow: hidden;
}
.progress-fill {
  height: 100%; width: 0%; background: #4f6ef7;
  transition: width 200ms ease;
}
#progressText { font-size: 0.82rem; color: #888; margin-top: 0.4rem; }

/* ── Share row ── */
.share-row {
  display: flex; align-items: center; gap: 0.6rem;
  background: #1a1c24; padding: 0.65rem 0.9rem; border-radius: 8px;
  border: 1px solid #2a2d38; margin-bottom: 1rem;
}
.share-row svg { color: #4f6ef7; flex-shrink: 0; }
.share-row code {
  font-size: 0.84rem; color: #8ed8ff; word-break: break-all; flex: 1;
}

/* ── Preview ── */
.preview-frame-wrap {
  margin-top: 0.8rem;
  border: 1px solid #2a2d38; border-radius: 10px;
  overflow: hidden; background: #323232;
}
.preview-frame {
  width: 100%; height: 500px; border: none; display: block;
}

/* ═══════════════════════════════
   VIEWER OVERLAY (full-screen)
   ═══════════════════════════════ */
.viewer-overlay {
  position: fixed; inset: 0; z-index: 9999;
  background: #323232;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  font-family: system-ui, -apple-system, sans-serif;
}

/* Book inside viewer */
.viewer-overlay .book {
  position: relative; transform-style: preserve-3d; perspective: 2400px;
  overflow: hidden; border-radius: 4px;
  box-shadow: 0 20px 60px rgba(0,0,0,0.55);
  transition: width 420ms cubic-bezier(0.4, 0, 0.2, 1), height 420ms cubic-bezier(0.4, 0, 0.2, 1);
}
.viewer-overlay .book::after {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(ellipse at 55% 40%,rgba(255,255,255,0.06),transparent 60%);
  pointer-events: none; z-index: 25;
}

/* Spread */
.viewer-overlay .spread {
  position: absolute; inset: 0; display: grid; grid-template-columns: 1fr 1fr;
}
.viewer-overlay .spine {
  position: absolute; top: 0; bottom: 0; left: 50%; width: 4px; transform: translateX(-2px);
  background: linear-gradient(to bottom,rgba(0,0,0,0.22),rgba(0,0,0,0.42) 50%,rgba(0,0,0,0.22));
  z-index: 10; pointer-events: none;
}
.viewer-overlay .spine::before, .viewer-overlay .spine::after {
  content: ""; position: absolute; top: 0; bottom: 0; width: 28px;
}
.viewer-overlay .spine::before { right: 100%; background: linear-gradient(to left,rgba(0,0,0,0.16),transparent); }
.viewer-overlay .spine::after { left: 100%; background: linear-gradient(to right,rgba(0,0,0,0.16),transparent); }

/* Page slots */
.viewer-overlay .ps { position: relative; overflow: hidden; background: #e8d9b8; }
.viewer-overlay .ps.l { box-shadow: inset -22px 0 26px -22px rgba(0,0,0,0.28); }
.viewer-overlay .ps.r { box-shadow: inset 22px 0 26px -22px rgba(0,0,0,0.24); }
.viewer-overlay .ps.blank { background: linear-gradient(135deg,#eadcbe,#e0cfaa); }
.viewer-overlay .ps img, .viewer-overlay .cv img, .viewer-overlay .bcv img, .viewer-overlay .sf img {
  width: 100%; height: 100%; object-fit: cover; display: block; user-select: none; pointer-events: none;
}

/* Front Cover */
.viewer-overlay .cv {
  position: absolute; inset: 0; z-index: 8; background: #d9c59f;
  box-shadow: 4px 4px 18px rgba(0,0,0,0.4), inset -18px 0 22px rgba(0,0,0,0.18);
  border-radius: 0 4px 4px 0;
}
/* Back Cover */
.viewer-overlay .bcv {
  position: absolute; inset: 0; z-index: 8; background: #d9c59f;
  box-shadow: -4px 4px 18px rgba(0,0,0,0.4), inset 18px 0 22px rgba(0,0,0,0.18);
  border-radius: 4px 0 0 4px;
}
/* Front closed */
.viewer-overlay .book.sc .spread { visibility: hidden; }
.viewer-overlay .book.sc .spine  { visibility: hidden; }
.viewer-overlay .book.sc .cv { visibility: visible; }
.viewer-overlay .book.sc .bcv { visibility: hidden; }
.viewer-overlay .book:not(.sc) .cv { visibility: hidden; }
/* Back closed */
.viewer-overlay .book.bc .spread { visibility: hidden; }
.viewer-overlay .book.bc .spine  { visibility: hidden; }
.viewer-overlay .book.bc .bcv { visibility: visible; }
.viewer-overlay .book.bc .cv { visibility: hidden; }
.viewer-overlay .book:not(.bc) .bcv { visibility: hidden; }

/* Flip sheet */
.viewer-overlay .fs {
  position: absolute; top: 0; bottom: 0; left: 50%; width: 50%;
  transform-origin: left center; transform-style: preserve-3d;
  will-change: transform; display: none; z-index: 16;
}
.viewer-overlay .book.tc .fs { left: 0; width: 100%; }
.viewer-overlay .fs.vis { display: block; }
.viewer-overlay .sf {
  position: absolute; inset: 0; backface-visibility: hidden; overflow: hidden; background: #ddcda9;
}
.viewer-overlay .sf.fr { box-shadow: inset -20px 0 28px rgba(0,0,0,0.22); }
.viewer-overlay .sf.bk { transform: rotateY(180deg); box-shadow: inset 20px 0 28px rgba(0,0,0,0.18); }

/* Fold shadow — dynamic gradient that follows the fold */
.viewer-overlay .fold-shadow {
  position: absolute; top: 0; bottom: 0; width: 60px;
  transform: translateX(-30px);
  background: linear-gradient(to right,
    transparent 0%,
    rgba(0,0,0,0.25) 35%,
    rgba(0,0,0,0.45) 50%,
    rgba(0,0,0,0.25) 65%,
    transparent 100%);
  z-index: 15; pointer-events: none; opacity: 0;
  transition: opacity 80ms ease;
}

/* Corner hint */
.viewer-overlay .ch {
  position: absolute; top: 0; right: 0; width: 14%; height: 20%;
  background: linear-gradient(140deg,rgba(255,255,255,0.45),rgba(173,126,73,0.22) 55%,transparent 75%);
  clip-path: polygon(100% 0,0 0,100% 100%); opacity: 0;
  transform: perspective(500px) rotateY(0) rotateX(0); transform-origin: top right;
  transition: opacity 180ms, transform 250ms; pointer-events: none; z-index: 22;
}
.viewer-overlay .ch::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(200deg,rgba(255,255,255,0.55),rgba(139,98,52,0.2));
  clip-path: inherit; opacity: .5;
}
.viewer-overlay .book.hf .ch { opacity: .9; transform: perspective(500px) rotateY(-28deg) rotateX(10deg); }
.viewer-overlay .book.hb .ch {
  right: auto; left: 0; transform-origin: top left;
  clip-path: polygon(0 0,100% 0,0 100%);
  background: linear-gradient(220deg,rgba(255,255,255,0.45),rgba(173,126,73,0.22) 55%,transparent 75%);
  opacity: .9; transform: perspective(500px) rotateY(28deg) rotateX(10deg);
}

/* Viewer controls */
.viewer-ctrls {
  display: flex; align-items: center; gap: 1.2rem; margin-top: 1rem; user-select: none;
}
.vn {
  width: 42px; height: 42px; border-radius: 50%;
  border: 1px solid rgba(255,255,255,0.2); background: rgba(255,255,255,0.08);
  color: #eee; font-size: 1rem; cursor: pointer;
  display: grid; place-content: center; transition: background 120ms;
}
.vn:hover { background: rgba(255,255,255,0.18); }
.vn:disabled { opacity: .35; cursor: default; }
#vpi { color: #bbb; font-size: .85rem; min-width: 110px; text-align: center; }

/* Hide admin UI when viewer active */
body.viewer-active .topbar,
body.viewer-active .main { display: none !important; }