:root{
  --leather:#15100A;
  --leather-2:#1E1610;
  --gold:#C9A227;
  --gold-deep:#8B6914;
  --cream:#F1E6C8;
  --cream-2:#E9DBAF;
  --ink:#2B2116;
  --ink-soft:#5B4E3C;
  --wax:#7A2E2E;
  --moss:#4B5E3C;
}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent;}
html,body{margin:0;padding:0;height:100%;background:var(--leather);overflow:hidden;}
body{
  font-family:'Inter',sans-serif;
  color:var(--ink);
  display:flex;
  flex-direction:column;
  height:100vh;
  height:100dvh;
}
@media (prefers-reduced-motion: reduce){
  *{transition-duration:.01ms !important; animation-duration:.01ms !important;}
}

/* ---------- top chrome ---------- */
#chrome-top{
  flex:0 0 auto;
  display:flex; align-items:center; justify-content:space-between;
  gap:10px;
  padding:10px 14px;
  background:linear-gradient(180deg, var(--leather-2), var(--leather));
  border-bottom:1px solid rgba(201,162,39,0.25);
  z-index:50;
}
.brand{
  display:flex; align-items:center; gap:8px;
  color:var(--gold);
  font-family:'Fraunces',serif; font-weight:600; font-size:15px;
  white-space:nowrap;
}
.brand img{ width:20px; height:20px; object-fit:cover; border-radius:3px; }
.ticker{
  font-family:'IBM Plex Mono',monospace;
  font-size:11px; color:#C9BFA0;
  display:flex; align-items:center; gap:6px;
  overflow:hidden; white-space:nowrap;
  flex:1;
  justify-content:center;
}
.ticker .dot{width:6px;height:6px;border-radius:50%;background:var(--moss);flex:0 0 auto;}
.ticker .ca-pill{
  background:rgba(255,255,255,0.06); border:1px solid rgba(201,162,39,0.3);
  border-radius:20px; padding:3px 10px; cursor:pointer; color:var(--gold);
  font-size:10.5px; display:flex; align-items:center; gap:5px;
}
.ticker .ca-pill:active{background:rgba(201,162,39,0.18);}
#buy-btn{
  flex:0 0 auto;
  background:var(--gold);
  color:var(--leather);
  border:none;
  font-family:'Inter',sans-serif; font-weight:700; font-size:12.5px;
  padding:9px 16px;
  border-radius:8px;
  letter-spacing:.02em;
  cursor:pointer;
  text-decoration:none;
  display:inline-block;
}
#buy-btn:active{background:#B08D1F;}

/* ---------- stage ---------- */
#stage{
  flex:1 1 auto;
  display:flex; align-items:center; justify-content:center;
  perspective:2400px;
  padding:14px 10px 6px;
  min-height:0;
  position:relative;
}
#book{
  position:relative;
  width:min(94vw, 460px);
  height:min(78vh, 92vw, 700px);
  aspect-ratio:5/7.6;
  max-height:82vh;
}
@media (min-width:820px){
  #book{ width:min(46vw, 520px); height:min(82vh,760px); }
}
.page{
  position:absolute; inset:0;
  background:var(--cream);
  border-radius:6px;
  box-shadow:0 18px 40px rgba(0,0,0,0.55), 0 2px 0 rgba(255,255,255,0.04) inset;
  overflow:hidden;
  background-image:
    radial-gradient(ellipse at 15% 10%, rgba(255,255,255,0.10), transparent 40%),
    linear-gradient(90deg, rgba(0,0,0,0.05), transparent 3%, transparent 97%, rgba(0,0,0,0.06));
}
.page::after{ /* gilded edge */
  content:"";
  position:absolute; top:0; right:0; bottom:0; width:5px;
  background:linear-gradient(180deg, var(--gold), var(--gold-deep), var(--gold));
  opacity:.85;
}
.page-inner{
  position:absolute; inset:0;
  padding:26px 24px 46px;
  display:flex; flex-direction:column;
  overflow:hidden;
}
.running-head{
  font-family:'IBM Plex Mono',monospace;
  font-size:10px; letter-spacing:.08em; text-transform:uppercase;
  color:var(--ink-soft); opacity:.65;
  margin-bottom:14px; padding-bottom:8px;
  border-bottom:1px solid rgba(43,33,22,0.15);
  display:flex; justify-content:space-between;
}
.chapter-kicker{
  font-family:'IBM Plex Mono',monospace; font-size:11px; letter-spacing:.12em;
  color:var(--wax); text-transform:uppercase; margin-bottom:6px;
}
.chapter-title{
  font-family:'Fraunces',serif; font-weight:600; font-size:26px; line-height:1.08;
  color:var(--ink); margin:0 0 6px;
}
.chapter-subtitle{
  font-family:'Literata',serif; font-style:italic; font-size:13.5px; color:var(--ink-soft);
  margin:0 0 16px; padding-bottom:14px; border-bottom:1px solid rgba(43,33,22,0.18);
}
.blk-p{
  font-family:'Literata',serif; font-size:14.5px; line-height:1.62;
  color:var(--ink); margin:0 0 12px; text-align:left;
}
.blk-h2{
  font-family:'Fraunces',serif; font-weight:600; font-size:16.5px;
  color:var(--wax); margin:14px 0 8px;
}
.blk-li{
  font-family:'Literata',serif; font-size:14px; line-height:1.5;
  color:var(--ink); margin:0 0 8px; padding-left:16px; position:relative;
}
.blk-li::before{content:"\2022"; position:absolute; left:2px; color:var(--gold-deep);}
.blk-quote{
  font-family:'Literata',serif; font-style:italic; font-size:14.5px; line-height:1.5;
  color:var(--ink-soft); margin:10px 0 14px; padding:10px 14px;
  border-left:3px solid var(--gold-deep); background:rgba(139,105,20,0.08);
}
.blk-quote .attr{display:block; font-style:normal; font-size:11px; margin-top:6px; color:var(--wax); font-family:'IBM Plex Mono',monospace;}
.blk-img{ text-align:center; margin:6px 0 14px; }
.blk-img img{ max-width:100%; max-height:220px; border-radius:4px; border:1px solid rgba(43,33,22,0.15); }
.blk-img .cap{ font-family:'IBM Plex Mono',monospace; font-size:10px; color:var(--ink-soft); margin-top:6px; line-height:1.4; }

/* flip mechanics */
#page-base{ z-index:1; }
.flip-container{
  position:absolute; inset:0;
  z-index:2;
  opacity:0;
  transform-style:preserve-3d;
  transform-origin:left center;
  transition:transform .55s cubic-bezier(.4,.05,.2,1);
  will-change:transform;
  pointer-events:none;
}
.face{
  position:absolute; inset:0;
  background:var(--cream);
  border-radius:6px;
  box-shadow:0 18px 40px rgba(0,0,0,0.55), 0 2px 0 rgba(255,255,255,0.04) inset;
  backface-visibility:hidden;
  overflow:hidden;
}
.face::after{
  content:"";
  position:absolute; top:0; right:0; bottom:0; width:5px;
  background:linear-gradient(180deg, var(--gold), var(--gold-deep), var(--gold));
  opacity:.85;
}
.face.back{ transform:rotateY(180deg); background:var(--cream-2); }
.face.back .watermark{
  position:absolute; inset:0; display:flex; align-items:center; justify-content:center;
  font-family:'Fraunces',serif; font-size:15px; color:rgba(43,33,22,0.18); letter-spacing:.06em;
  text-align:center; padding:30px; transform:scaleX(-1);
}
.flip-shadow{
  position:absolute; inset:0; background:linear-gradient(90deg, rgba(0,0,0,0) 60%, rgba(0,0,0,0.35));
  opacity:0; pointer-events:none; transition:opacity .55s;
}

/* ---------- cover (vector art, no photo) ---------- */
.cover-page{
  position:absolute; inset:0; border-radius:6px; overflow:hidden;
  background-color:var(--leather);
  color:var(--cream);
  display:flex; flex-direction:column; align-items:center; justify-content:flex-end;
  text-align:center; padding:22px 22px 20px;
}
.cover-cta{
  display:flex; flex-direction:column; gap:8px; width:100%; max-width:250px;
}
.cover-cta a, .cover-cta button{
  font-family:'Inter',sans-serif; font-weight:700; font-size:13.5px;
  padding:11px 16px; border-radius:9px; border:none; cursor:pointer;
  text-decoration:none; display:block;
}
.cta-buy{ background:var(--gold); color:var(--leather); }
.cta-ca{ background:transparent; color:var(--gold); border:1px solid rgba(201,162,39,0.5) !important; font-family:'IBM Plex Mono',monospace !important; font-weight:500 !important; font-size:10.5px !important; word-break:break-all; }
.social-row{ display:flex; gap:12px; justify-content:center; margin-top:12px; }
.social-btn{
  width:38px; height:38px; border-radius:50%; background:rgba(255,255,255,0.06);
  border:1px solid rgba(201,162,39,0.4); display:flex; align-items:center; justify-content:center;
  color:var(--gold); text-decoration:none;
}
.social-btn svg{ width:18px; height:18px; }
.social-btn img{ width:18px; height:18px; object-fit:contain; }
.swipe-hint{
  margin-top:14px; font-family:'IBM Plex Mono',monospace; font-size:10.5px;
  color:#9C8F70; letter-spacing:.05em; display:flex; flex-direction:column; align-items:center; gap:4px;
  animation:hintpulse 2.2s ease-in-out infinite;
}
@keyframes hintpulse{ 0%,100%{opacity:.4;} 50%{opacity:1;} }

.back-page{
  position:absolute; inset:0; border-radius:6px; overflow:hidden;
  background:linear-gradient(160deg, var(--leather-2), var(--leather) 60%);
  color:var(--cream); display:flex; flex-direction:column; align-items:center; justify-content:center;
  text-align:center; padding:34px 26px;
}
.back-page h2{ font-family:'Fraunces',serif; color:var(--gold); font-size:22px; margin:0 0 10px;}
.back-page p{ font-family:'Literata',serif; font-size:13px; color:#D9CBA3; max-width:280px; line-height:1.6; margin:0 0 18px;}
.disclaimer{ font-family:'IBM Plex Mono',monospace; font-size:9.5px; color:#8A7E63; max-width:260px; line-height:1.5; }

/* tap zones */
.tapzone{ position:absolute; top:0; bottom:0; width:26%; z-index:10; cursor:pointer; }
.tapzone.left{ left:0; }
.tapzone.right{ right:0; }

/* ---------- bottom chrome ---------- */
#chrome-bottom{
  flex:0 0 auto;
  display:flex; align-items:center; justify-content:space-between;
  padding:8px 16px 12px;
  background:var(--leather);
}
.navbtn{
  background:none; border:1px solid rgba(201,162,39,0.35); color:var(--gold);
  width:34px; height:34px; border-radius:50%; font-size:15px; cursor:pointer;
  display:flex; align-items:center; justify-content:center;
}
.navbtn:disabled{ opacity:.25; }
@media (min-width:820px){
  .navbtn{ display:none; }
  #chrome-bottom{ justify-content:center; gap:24px; }
}
#page-indicator{
  font-family:'IBM Plex Mono',monospace; font-size:10.5px; color:#B7A876;
  text-align:center; flex:1; overflow:hidden; white-space:nowrap; text-overflow:ellipsis; padding:0 8px;
}
#contents-btn{
  background:none; border:none; color:var(--gold); font-size:17px; cursor:pointer; width:34px; height:34px;
}
#nav-hint{
  flex:0 0 auto; text-align:center; padding:0 0 8px;
  font-family:'IBM Plex Mono',monospace; font-size:9px; letter-spacing:.04em;
  color:#7A6E52; background:var(--leather);
}

/* contents drawer */
#drawer-overlay{
  position:fixed; inset:0; background:rgba(0,0,0,0.55); z-index:100;
  opacity:0; pointer-events:none; transition:opacity .25s;
}
#drawer-overlay.open{ opacity:1; pointer-events:auto; }
#drawer{
  position:absolute; bottom:0; left:0; right:0; max-height:70vh;
  background:var(--cream); border-radius:16px 16px 0 0;
  transform:translateY(100%); transition:transform .3s cubic-bezier(.32,.72,0,1);
  overflow-y:auto; padding:18px 6px 30px;
}
#drawer-overlay.open #drawer{ transform:translateY(0); }
#drawer h3{
  font-family:'Fraunces',serif; color:var(--ink); text-align:center; margin:0 0 12px; font-size:16px;
}
.drawer-item{
  display:flex; justify-content:space-between; align-items:baseline;
  padding:11px 20px; font-family:'Inter',sans-serif; font-size:13.5px; color:var(--ink);
  border-bottom:1px solid rgba(43,33,22,0.08); cursor:pointer;
}
.drawer-item:active{ background:rgba(139,105,20,0.08); }
.drawer-item .num{ font-family:'IBM Plex Mono',monospace; font-size:10.5px; color:var(--wax); margin-right:10px; }
.drawer-item .pg{ font-family:'IBM Plex Mono',monospace; font-size:10.5px; color:var(--ink-soft); }

#measurer{
  position:absolute; visibility:hidden; pointer-events:none; left:-9999px; top:0;
}
#btn-prev-desktop, #btn-next-desktop{
  display:none;
}
@media (min-width:820px){
  #btn-prev-desktop, #btn-next-desktop{
    display:flex; align-items:center; justify-content:center;
    position:absolute; top:50%; transform:translateY(-50%);
    width:46px; height:46px; border-radius:50%;
    background:var(--leather-2); border:1px solid rgba(201,162,39,0.4);
    color:var(--gold); font-size:22px; cursor:pointer;
    z-index:60;
  }
  #btn-prev-desktop{ left:calc(50% - min(23vw, 260px) - 66px); }
  #btn-next-desktop{ left:calc(50% + min(23vw, 260px) + 20px); }
  #btn-prev-desktop:disabled, #btn-next-desktop:disabled{ opacity:.25; cursor:default; }
  #btn-prev-desktop:not(:disabled):hover, #btn-next-desktop:not(:disabled):hover{ background:rgba(201,162,39,0.15); }
}
.measure-box{
  padding:26px 24px 46px;
  box-sizing:border-box;
  font-family:'Literata',serif;
}