/* ══════════════════════════════════════════════
   《初阅 · 绝笔》—— 一本会翻页的信
   ══════════════════════════════════════════════ */

:root{
  /* 夜与月 */
  --night:#0A0809;
  --night-2:#141013;
  --moon:#E7E2DA;
  --mist:#D6DCE3;
  /* 纸与墨 */
  --paper:#EFE7D6;
  --paper-2:#E1D5BE;
  --paper-3:#D6C7AB;
  --ink:#241E1A;
  --ink-2:#3A312A;
  --ink-3:#7C6D58;
  /* 金与血 */
  --gold:#B8956A;
  --gold-2:#D8BE94;
  --blood:#8B1A1A;
  --blood-2:#B03030;

  --brush:"Ma Shan Zheng","STKaiti","KaiTi","楷体",serif;
  --hand:"Zhi Mang Xing","STKaiti","KaiTi","楷体",cursive;
  --kai:"KaiTi","楷体","STKaiti","楷体_GB2312","Kaiti SC",serif;
  --song:"Noto Serif SC","Source Han Serif SC","Songti SC","STSong","SimSun",serif;

  --ease:cubic-bezier(.16,.84,.28,1);
  --flip:cubic-bezier(.52,.02,.28,1);
}

*{margin:0;padding:0;box-sizing:border-box}
html,body{height:100%}
body{
  background:var(--night);
  color:var(--moon);
  font-family:var(--song);
  font-weight:300;
  overflow:hidden;
  -webkit-font-smoothing:antialiased;
  -webkit-tap-highlight-color:transparent;
}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
img{display:block;max-width:100%}
[hidden]{display:none!important}

/* ══════════════════════════════════════════════
   封面
   ══════════════════════════════════════════════ */
/* ── 封面：主图一张不裁，尽量占满；拆封盖在信纸上 ──
   封面是 941×1672 竖图。要走"不裁图"，就只能按 contain 摆 ——
   横屏时图会受高度限制，两侧留空，用同图虚化铺底把屏幕填满（虚化的是底，主图本身不裁）。
   主图框的尺寸直接写成 contain 的解析式，于是框 = 图片在屏幕上的实际占据区域，
   印章只要写在框内的百分比坐标（83.0% 80.5% = 信纸中心），任何屏幕比例都落在纸上。 */
.cover{
  position:fixed;inset:0;z-index:40;overflow:hidden;
  background:#0A0809;
  transition:opacity .9s var(--ease);
}
.cover.gone{opacity:0;pointer-events:none}

.cover-bg{
  position:absolute;inset:0;
  background:url("assets/cover.jpg") center/cover no-repeat;
  filter:blur(64px) brightness(.44) saturate(1.15);
  transform:scale(1.22);
}
/* 主图四周轻轻收暗，让它在虚化底上"浮"出来（压在虚化底之上、主图之下） */
.cover::after{
  content:"";position:absolute;inset:0;z-index:1;pointer-events:none;
  background:radial-gradient(120% 88% at 50% 46%,transparent 46%,rgba(8,6,7,.55) 100%);
}

.cover-frame{
  position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);z-index:2;
  width:min(100vw,calc(100vh * .5628));
  height:min(calc(100vw * 1.7768),100vh);
  container-type:size;                    /* 印章尺寸按框高走，见 .wax */
  box-shadow:0 34px 90px -26px rgba(0,0,0,.92);
}
@supports (height:100dvh){
  .cover-frame{width:min(100vw,calc(100dvh * .5628));height:min(calc(100vw * 1.7768),100dvh)}
}
/* 框的比例就是图片比例，cover 在这里等于不裁 */
.cover-art{width:100%;height:100%;object-fit:cover;display:block;
  animation:coverIn 1.7s var(--ease) both}

/* ── 拆封：一枚盖在信纸上的朱砂印 ──
   信纸在原图上只有 174×72px。尺寸按"框高"的百分比走（5.6cqh），
   这样无论在横屏还是手机上，印章与信纸的相对大小都稳定 */
.wax{
  position:absolute;
  left:83.0%;top:80.5%;
  width:clamp(48px,5.6cqh,64px);
  aspect-ratio:1;border-radius:50%;
  transform:translate(-50%,-50%);
  animation:waxIn 1.1s var(--ease) .55s both;
  transition:filter .35s;
}
@supports not (width:1cqh){
  .wax{width:clamp(48px,5.6vh,64px)}
}
.wax-face{
  position:absolute;inset:0;border-radius:50%;
  display:flex;align-items:center;justify-content:center;
  background:radial-gradient(circle at 34% 28%,#C8503C,#A62B22 46%,#7C1A15 100%);
  box-shadow:
    inset 0 0 0 1px rgba(246,239,226,.36),
    0 0 0 4px rgba(166,43,34,.26),
    0 10px 26px -8px rgba(0,0,0,.92),
    0 0 46px -6px rgba(176,48,48,.6);
}
.wax-txt{
  font-family:var(--brush);
  font-size:clamp(13px,1.55vw,24px);
  letter-spacing:.06em;text-indent:.06em;
  color:#F6EFE2;
  text-shadow:0 1px 3px rgba(80,10,8,.75);
}
/* 一圈轻轻扩散的金环，把视线引过来，不吵 */
.wax::after{
  content:"";position:absolute;inset:-6%;border-radius:50%;
  border:1px solid rgba(184,149,106,.5);
  animation:waxRing 3.6s ease-in-out 1.9s infinite;
}
.wax:hover{filter:brightness(1.14)}
.wax:active{filter:brightness(.92)}
.wax:focus-visible{outline:2px solid var(--gold-2);outline-offset:6px}

@keyframes coverIn{
  from{opacity:0;transform:scale(1.06);filter:blur(7px)}
  to  {opacity:1;transform:none;filter:blur(0)}
}
/* 元素本身有 translate(-50%,-50%) 定位，动画必须把它一起写进去，否则会被覆盖 */
@keyframes waxIn{
  from{opacity:0;transform:translate(-50%,-50%) scale(.7)}
  to  {opacity:1;transform:translate(-50%,-50%) scale(1)}
}
@keyframes waxRing{
  0%  {transform:scale(1);opacity:.5}
  72% {transform:scale(1.55);opacity:0}
  100%{transform:scale(1.55);opacity:0}
}
@keyframes riseIn{from{opacity:0;transform:translateY(14px)}to{opacity:1;transform:none}}

/* ══════════════════════════════════════════════
   书
   ══════════════════════════════════════════════ */
.book{
  position:fixed;inset:0;z-index:20;
  display:flex;flex-direction:column;align-items:center;justify-content:center;
  gap:clamp(8px,1.5vh,16px);
  padding:clamp(10px,2vh,26px) 16px;
  opacity:0;
}
/* 用 animation 而不是 transition：过渡在某些渲染环境下不推进，
   动画（含 forwards）更稳，最终态一定到位 */
.book.in{animation:bookIn .95s var(--ease) forwards}
@keyframes bookIn{from{opacity:0}to{opacity:1}}

/* 包一层：翻页按钮要钉在书页的左右两侧，所以需要一个"刚好等于书"的定位父级 */
.stage-wrap{position:relative;flex:none}

.book-stage{
  position:relative;z-index:1;             /* 必须自成层叠上下文！
     桌面靠 perspective 顺带形成了，手机媒体查询里把 perspective 关掉之后
     书页的 z-index（220）会逃出来盖住左右翻页箭头 —— 显式给个 z-index 才稳 */
  width:min(94vw,calc(82vh * 1.77778));
  height:min(calc(94vw * .5625),82vh);
  perspective:2400px;
  perspective-origin:50% 50%;
  background:#0E0A0C;
  box-shadow:0 46px 110px -34px rgba(0,0,0,.95),0 0 0 1px rgba(184,149,106,.2),
             0 0 90px -50px rgba(184,149,106,.35);
}
@supports (height:100dvh){
  .book-stage{width:min(94vw,calc(82dvh * 1.77778));height:min(calc(94vw * .5625),82dvh)}
}

/* ─── 页 ─── */
.page{
  position:absolute;inset:0;
  overflow:hidden;
  background:#0E0A0C;
  transform-origin:left center;
  backface-visibility:hidden;
  -webkit-backface-visibility:hidden;
  transition:transform .9s var(--flip);
  will-change:transform;
}
.page.turned{transform:rotateY(-180deg)}

.page-art{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}

/* 书脊侧的暗部 + 右上角压暗（书耳压在亮图上会看不见）。
   这一层只建在有配图的页上，纯纸页的书耳是深色字，不需要它 */
.page-gutter{
  position:absolute;inset:0;pointer-events:none;
  background:
    radial-gradient(44% 40% at 100% 0%,rgba(10,8,9,.52),transparent 74%),
    linear-gradient(to right,rgba(10,8,9,.55) 0,rgba(10,8,9,.16) 4.5%,transparent 13%);
}
/* 底部压暗，托住信纸带 */
.page-scrim{
  position:absolute;left:0;right:0;bottom:0;height:66%;pointer-events:none;
  background:linear-gradient(to top,rgba(12,9,10,.9) 0,rgba(12,9,10,.6) 34%,rgba(12,9,10,.2) 66%,transparent 100%);
}

/* 右上角竖排书耳：页序 + 小标题 */
.page-mark{
  position:absolute;right:clamp(10px,1.6vw,26px);top:clamp(10px,1.8vh,24px);z-index:3;
  display:flex;align-items:flex-start;gap:6px;
  writing-mode:vertical-rl;
  text-shadow:0 2px 14px rgba(0,0,0,.95);
}
.page-no{
  font-family:var(--brush);font-size:clamp(15px,1.7vw,22px);
  letter-spacing:.14em;color:rgba(231,226,218,.9);
}
.page-name{
  font-family:var(--kai);font-size:clamp(10px,1.05vw,13px);
  letter-spacing:.34em;color:rgba(214,220,227,.6);
}

/* ─── 信纸带 ─── */
.page-text{
  position:absolute;left:0;right:0;bottom:0;
  padding:clamp(40px,6.6vh,76px) clamp(24px,4.6vw,78px) clamp(20px,3.4vh,42px);
  background:linear-gradient(to bottom,var(--paper) 0%,var(--paper) 58%,var(--paper-2) 100%);
  -webkit-mask-image:linear-gradient(to bottom,transparent 0,#000 26px,#000 100%);
  mask-image:linear-gradient(to bottom,transparent 0,#000 26px,#000 100%);
}
/* 纸张纤维/水渍 */
.page-text::after{
  content:"";position:absolute;inset:0;pointer-events:none;
  background:
    radial-gradient(60% 120% at 12% 0%,rgba(150,126,92,.13),transparent 62%),
    radial-gradient(44% 90% at 88% 100%,rgba(126,104,72,.11),transparent 66%);
}
/* 上沿一道细金线 */
.page-text::before{
  content:"";position:absolute;left:clamp(24px,4.6vw,78px);right:clamp(24px,4.6vw,78px);top:clamp(24px,3.6vh,40px);
  height:1px;
  background:linear-gradient(to right,transparent,rgba(160,128,84,.5) 18%,rgba(160,128,84,.5) 82%,transparent);
  pointer-events:none;
}

.page-body{position:relative}
.page-body p{
  font-family:var(--kai);font-weight:400;
  font-size:clamp(13.5px,1.32vw,19px);
  line-height:2;
  letter-spacing:.06em;
  color:var(--ink);
  text-align:justify;
  text-justify:inter-ideograph;
  text-wrap:balance;             /* 首行缩进会把最后一行挤成两三个字，balance 摊匀 */
  text-indent:2em;
  opacity:0;
}
/* 每段依次浮上来，延迟由 JS 写进 --d */
.page-body p.in{animation:lineIn .95s var(--ease) both;animation-delay:var(--d,0ms)}
@keyframes lineIn{
  from{opacity:0;transform:translateY(14px)}
  to  {opacity:1;transform:none}
}
.page-body p + p{margin-top:.5em}
/* 称呼：顶格，不缩进，比正文大一号 */
.page-body p.salute{
  text-indent:0;text-align:left;
  font-family:var(--brush);font-weight:400;
  font-size:clamp(15px,1.5vw,21px);
  letter-spacing:.14em;
  color:var(--ink-2);
  margin-bottom:.5em;
}
/* 短句：去缩进、居中放大，当重锤用 */
.page-body p.solo{
  text-indent:0;text-align:center;
  font-family:var(--brush);font-weight:400;
  font-size:clamp(16px,1.7vw,24px);
  letter-spacing:.16em;
  line-height:1.9;
  color:var(--ink-2);
}
.page-body p.solo + p.solo{margin-top:.1em}

/* 落款 */
.page-body p.solo.sign-line{color:var(--ink-2)}
.seal{
  display:block;margin:clamp(8px,1.6vh,18px) clamp(6px,1vw,16px) 0 auto;
  writing-mode:vertical-rl;
  font-family:var(--brush);font-size:clamp(13px,1.24vw,17px);letter-spacing:.2em;
  color:#F6EFE2;
  background:var(--blood);
  padding:9px 7px;
  border-radius:2px;
  box-shadow:0 4px 16px -6px rgba(139,26,26,.8);
  opacity:0;
}
.seal.in{animation:sealIn .9s var(--ease) both;animation-delay:var(--d,0ms)}
@keyframes sealIn{
  from{opacity:0;transform:translateY(8px) scale(.94)}
  to  {opacity:1;transform:none}
}

/* ══════════════════════════════════════════════
   第柒页 · 验证（没有配图的那页）
   —— 全站唯一的纯纸页，血在纸上慢慢化开
   ══════════════════════════════════════════════ */
.page.ember{
  background:linear-gradient(168deg,#F2EADB 0%,#E8DCC4 52%,#DBCBAE 100%);
}
.page.ember::before{
  content:"";position:absolute;inset:0;pointer-events:none;
  background:
    radial-gradient(42% 38% at 50% 44%,rgba(139,26,26,.30),rgba(139,26,26,.10) 46%,transparent 74%),
    radial-gradient(70% 120% at 8% 0%,rgba(150,126,92,.16),transparent 60%),
    radial-gradient(50% 90% at 94% 100%,rgba(120,98,68,.14),transparent 62%);
}
.embers{position:absolute;inset:0;pointer-events:none;overflow:hidden}
.embers i{
  position:absolute;border-radius:50%;
  background:radial-gradient(circle at 34% 32%,rgba(214,86,86,.9),rgba(139,26,26,.72) 58%,rgba(139,26,26,0) 72%);
  opacity:0;
  animation:emberUp linear infinite;
}
@keyframes emberUp{
  0%  {opacity:0;transform:translate3d(0,0,0) scale(.5)}
  12% {opacity:.85}
  70% {opacity:.5}
  100%{opacity:0;transform:translate3d(var(--dx,10px),-90px,0) scale(1.5)}
}
/* 纯纸页：文字居中竖排感，不用底部信纸带 */
.page.ember .page-text{
  top:0;
  display:flex;align-items:center;justify-content:center;
  padding:clamp(30px,6vh,70px) clamp(26px,7vw,120px);
  background:none;
  -webkit-mask-image:none;mask-image:none;
}
.page.ember .page-text::before,.page.ember .page-text::after{display:none}
.page.ember .page-body{max-width:min(100%,880px)}
.page.ember .page-body p{
  color:#3A1A18;
  font-size:clamp(13.5px,1.28vw,18px);
  line-height:2.2;
  text-indent:2em;
}
.page.ember .page-mark .page-no{color:rgba(58,26,24,.85)}
.page.ember .page-mark .page-name{color:rgba(58,26,24,.5)}

/* ══════════════════════════════════════════════
   尾页
   ══════════════════════════════════════════════ */
.page.end{background:linear-gradient(170deg,#F2EADB,#E5D9C0 58%,#D9C9AB)}
.page.end::before{
  content:"";position:absolute;inset:0;pointer-events:none;
  background:
    radial-gradient(70% 110% at 10% 0%,rgba(150,126,92,.15),transparent 60%),
    radial-gradient(52% 88% at 92% 100%,rgba(120,98,68,.13),transparent 62%);
}
.end-inner{
  position:absolute;inset:0;
  display:flex;flex-direction:column;align-items:center;justify-content:center;
  gap:clamp(18px,4vh,44px);
  padding:clamp(26px,6vw,90px);
}
.end-line{
  font-family:var(--brush);font-weight:400;
  font-size:clamp(20px,2.6vw,40px);
  letter-spacing:.2em;text-indent:.2em;
  color:var(--ink);
  text-align:center;
  opacity:0;
}
.end-line.in{animation:endIn 1.3s var(--ease) both;animation-delay:var(--d,0ms)}
@keyframes endIn{
  from{opacity:0;transform:translateY(14px)}
  to  {opacity:1;transform:none}
}
.end-again{
  font-family:var(--kai);font-size:clamp(11px,1.1vw,14px);
  letter-spacing:.3em;text-indent:.3em;
  color:var(--ink-3);
  padding:10px 26px;
  border:1px solid rgba(124,109,88,.42);
  border-radius:999px;
  opacity:0;
  transition:color .3s,border-color .3s,background .3s;
}
.end-again.in{animation:endIn .9s var(--ease) both;animation-delay:var(--d,0ms)}
.end-again:hover{color:var(--blood);border-color:rgba(139,26,26,.5);background:rgba(139,26,26,.05)}
.end-seal{
  font-family:var(--brush);font-size:clamp(12px,1.2vw,16px);letter-spacing:.2em;
  color:#F6EFE2;background:var(--blood);
  writing-mode:vertical-rl;padding:8px 6px;border-radius:2px;
  opacity:0;
}
.end-seal.in{animation:endIn .9s var(--ease) both;animation-delay:var(--d,0ms)}

/* ══════════════════════════════════════════════
   翻页导航：箭头贴在书页左右两侧（竖排居中），页码沉底
   ══════════════════════════════════════════════ */
.nav-btn{
  position:absolute;top:50%;z-index:30;
  width:clamp(38px,3.2vw,46px);height:clamp(38px,3.2vw,46px);border-radius:50%;
  transform:translateY(-50%);
  display:flex;align-items:center;justify-content:center;
  color:rgba(231,226,218,.9);
  border:1px solid rgba(184,149,106,.44);
  background:rgba(14,10,12,.6);
  -webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);
  box-shadow:0 8px 24px -10px rgba(0,0,0,.9);
  transition:border-color .3s,color .3s,background .3s,opacity .3s;
}
.nav-prev{left:clamp(8px,1.4vw,20px)}
.nav-next{right:clamp(8px,1.4vw,20px)}
.nav-btn svg{width:19px;height:19px}
.nav-btn:hover{border-color:var(--gold-2);color:var(--gold-2);background:rgba(184,149,106,.18)}
/* 到头了也别让它整个消失，否则只看见一个箭头，像坏了 */
.nav-btn:disabled{opacity:.32;cursor:default}
.nav-btn:disabled:hover{border-color:rgba(184,149,106,.44);color:rgba(231,226,218,.9);background:rgba(14,10,12,.6)}

.pager{
  font-family:var(--kai);font-size:clamp(11px,1.1vw,14px);
  letter-spacing:.3em;
  color:rgba(231,226,218,.5);
  min-width:5.6em;text-align:center;
}
.pager b{color:var(--gold-2);font-weight:400;letter-spacing:.16em}

.book-hint{
  font-family:var(--kai);font-size:clamp(10px,1vw,12px);
  letter-spacing:.28em;text-indent:.28em;
  color:rgba(231,226,218,.34);
  transition:opacity .8s ease;
}
.book-hint.gone{opacity:0}

/* ══════════════════════════════════════════════
   音乐
   ══════════════════════════════════════════════ */
.music{
  position:fixed;right:clamp(14px,2vw,26px);bottom:clamp(14px,2.4vh,26px);
  z-index:95;
  width:44px;height:44px;border-radius:50%;
  display:flex;align-items:center;justify-content:center;
  color:rgba(236,229,216,.82);
  border:1px solid rgba(236,229,216,.36);
  background:rgba(14,10,12,.6);
  box-shadow:0 8px 26px -12px rgba(0,0,0,.95);
  -webkit-backdrop-filter:blur(6px);backdrop-filter:blur(6px);
  transition:border-color .3s,color .3s,background .3s;
}
.music svg{width:20px;height:20px}
.music:hover{border-color:var(--gold-2);color:var(--gold-2);background:rgba(184,149,106,.12)}
.music.on{color:var(--gold-2);border-color:rgba(184,149,106,.46);background:rgba(184,149,106,.1)}
.music.off{color:rgba(236,229,216,.64);border-color:rgba(236,229,216,.34)}
.music.off{animation:musicNudge 2.6s ease-in-out 1.1s 3}
@keyframes musicNudge{
  0%,100%{box-shadow:0 8px 26px -12px rgba(0,0,0,.95),0 0 0 0 rgba(184,149,106,0)}
  50%    {box-shadow:0 8px 26px -12px rgba(0,0,0,.95),0 0 0 9px rgba(184,149,106,.1)}
}
.music-slash{opacity:0;transition:opacity .3s}
.music.off .music-slash{opacity:1}
.music.on{animation:musicRipple 3.6s ease-in-out infinite}
@keyframes musicRipple{
  0%,100%{box-shadow:0 8px 26px -12px rgba(0,0,0,.95),0 0 0 0 rgba(184,149,106,0)}
  50%    {box-shadow:0 8px 26px -12px rgba(0,0,0,.95),0 0 0 7px rgba(184,149,106,.08)}
}

.unlock{
  position:fixed;right:clamp(14px,2vw,26px);bottom:calc(clamp(14px,2.4vh,26px) + 54px);
  z-index:95;
  font-family:var(--kai);font-size:clamp(11px,1.1vw,13px);
  letter-spacing:.2em;
  color:rgba(236,229,216,.88);
  /* 托一层暗底：不然落在浅色信纸那几页上，浅字会直接糊掉 */
  padding:6px 12px 6px 14px;
  border-radius:999px;
  background:rgba(14,10,12,.66);
  -webkit-backdrop-filter:blur(6px);backdrop-filter:blur(6px);
  white-space:nowrap;text-align:right;pointer-events:none;
  animation:unlockIn .8s var(--ease) both;
  transition:opacity .6s ease;
}
@keyframes unlockIn{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:none}}
.unlock.gone{opacity:0}

/* ══════════════════════════════════════════════
   窄屏 / 竖屏：16:9 的书页放不下，
   改成"上图 + 下信纸"的竖排阅读，翻页换淡入横移
   ══════════════════════════════════════════════ */
@media (max-width:880px),(max-aspect-ratio:1/1){
  .book{padding:0;gap:0;justify-content:flex-start}
  .stage-wrap{width:100%;height:100dvh;height:100vh}
  .book-stage{
    width:100%;height:100%;
    perspective:none;
    box-shadow:none;
    display:flex;flex-direction:column;
    background:var(--night);
  }
  .page{
    transform:none!important;
    transform-origin:center;
    transition:opacity .55s var(--ease);
    opacity:0;visibility:hidden;pointer-events:none;
    display:flex;flex-direction:column;
    background:var(--night);
  }
  .page.active{opacity:1;visibility:visible;pointer-events:auto}

  /* 图在上 */
  .page-art{
    position:relative;inset:auto;
    width:100%;height:auto;aspect-ratio:16/9;
    object-fit:cover;flex:none;
  }
  .page-gutter,.page-scrim{display:none}

  /* 信纸带在下，撑满剩下的高度，长了可以滚 */
  .page-text{
    position:relative;inset:auto;
    flex:1 1 auto;min-height:0;
    overflow-y:auto;-webkit-overflow-scrolling:touch;
    padding:clamp(26px,4.6vh,44px) clamp(22px,6vw,44px) clamp(70px,10vh,110px);
    -webkit-mask-image:linear-gradient(to bottom,transparent 0,#000 22px,#000 100%);
    mask-image:linear-gradient(to bottom,transparent 0,#000 22px,#000 100%);
  }
  .page-text::before{top:clamp(18px,3vh,30px)}
  .page-body p{font-size:clamp(14px,3.9vw,17px);line-height:2}
  .page-body p.solo{font-size:clamp(17px,5vw,23px)}

  .page-mark{
    right:auto;left:clamp(12px,4vw,20px);top:clamp(12px,2vh,20px);
    writing-mode:horizontal-tb;
  }
  .page-no{font-size:clamp(15px,4.4vw,20px)}
  .page-name{letter-spacing:.24em}

  /* 纯纸页 & 尾页：整屏都能滚 */
  .page.ember .page-text{top:auto;display:block;overflow-y:auto;padding-top:clamp(60px,12vh,110px)}
  .page.ember .page-body p{font-size:clamp(14px,3.9vw,17px)}
  .end-inner{position:relative;inset:auto;flex:1 1 auto;overflow-y:auto}

  .book-hint{display:none}
  /* 手机上留不出书外的空间，箭头就压在画面左右边缘 */
  .nav-prev{left:6px}
  .nav-next{right:6px}
  /* 竖屏时书页占满整屏，页码会被挤出视口，改成钉在底部 */
  .pager{
    position:fixed;left:0;right:0;bottom:clamp(10px,2.4vh,20px);z-index:60;
    padding-right:64px;              /* 给右下角音乐按钮让位 */
    text-shadow:0 2px 10px rgba(0,0,0,.85);
  }
}

/* 矮屏：印章跟着框高收，免得糊住信纸 */
@media (max-height:680px) and (min-aspect-ratio:1/1){
  .wax{width:clamp(48px,6.4cqh,60px)}
}

/* 减少动态效果：把入场动画整个关掉，并**显式把最终态写死**。
   不能只写 animation:none —— 那样元素会退回基础态（opacity:0），字直接消失。
   顺带这也是一个可靠的"静态取景"开关：无头截图加
   --force-prefers-reduced-motion 就能拍到所有元素到位的最终帧。 */
@media (prefers-reduced-motion:reduce){
  .page{transition-duration:.2s}
  .embers i{display:none}
  .book.in{animation:none;opacity:1}
  .cover-art{animation:none;opacity:1}
  .wax,.wax::after,.unlock,.music.off,.music.on{animation:none}
  .page-body p.in,.seal.in,.end-line.in,.end-again.in,.end-seal.in{
    animation:none;opacity:1;transform:none;
  }
}