/* =========================================================================
   纯七 答案之书 · 样式
   视觉主张：暖纸 / 宋体标题 / 鼠尾草·陶土·暮紫三色 / 克制的动效
   —— 不追求「好看」，追求「能安静待一会儿」
   ========================================================================= */

:root {
  --paper:      #faf6ef;
  --paper-2:    #f3ece1;
  --paper-3:    #ece3d4;
  --card:       rgba(255, 253, 248, .74);
  --card-solid: #fffdf8;

  --ink:        #35302b;
  --ink-2:      #6b625a;
  --ink-3:      #948a80;
  --ink-4:      #b6ada2;

  --sage:       #9db3a3;
  --clay:       #c98b7a;
  --dusk:       #7d7196;
  --gold:       #c8a05a;

  --line:       rgba(58, 51, 44, .13);
  --line-2:     rgba(58, 51, 44, .09);

  --grad:       linear-gradient(118deg, #c98b7a 0%, #c8a05a 46%, #9db3a3 100%);
  --grad-soft:  linear-gradient(118deg, rgba(201,139,122,.16), rgba(200,160,90,.14) 50%, rgba(157,179,163,.16));

  --r:          16px;
  --r-lg:       26px;
  --r-sm:       10px;

  --serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", STSong, SimSun, "Times New Roman", serif;
  --sans:  "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;

  --shadow:     0 2px 4px rgba(58,51,44,.03), 0 14px 38px -18px rgba(58,51,44,.16);
  --shadow-lg:  0 4px 10px rgba(58,51,44,.04), 0 30px 70px -30px rgba(58,51,44,.22);
  --ease:       cubic-bezier(.22, .61, .36, 1);
}

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  overflow-x: clip;
}

body {
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink);
  background: var(--paper);
  min-height: 100vh;
  overflow-x: clip;
  -webkit-font-smoothing: antialiased;
  display: flex;
  flex-direction: column;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -3;
  background:
    radial-gradient(56% 44% at 84% 2%,  rgba(200,160,90,.17), transparent 64%),
    radial-gradient(52% 46% at 4% 10%,  rgba(157,179,163,.20), transparent 66%),
    radial-gradient(58% 50% at 78% 88%, rgba(201,139,122,.15), transparent 64%),
    radial-gradient(46% 42% at 16% 84%, rgba(125,113,150,.16), transparent 64%),
    linear-gradient(180deg, #fdfaf4 0%, #f6efe2 100%);
}

/* 纸纹理：极细噪点，避免大片纯色的廉价感 */
.paper-tex {
  position: fixed;
  inset: 0;
  z-index: -2;
  pointer-events: none;
  opacity: .42;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.86' numOctaves='3'/%3E%3CfeColorMatrix type='saturate' values='0'/%3E%3C/filter%3E%3Crect width='180' height='180' filter='url(%23n)' opacity='.28'/%3E%3C/svg%3E");
  mix-blend-mode: multiply;
}

.glow-layer { position: fixed; inset: 0; z-index: -1; pointer-events: none; overflow: hidden; }
.glow-layer .g {
  position: absolute;
  border-radius: 50%;
  /* 用径向渐变代替 filter:blur —— blur 在 fixed 合成层上会留下硬边伪影 */
  animation: drift 26s var(--ease) infinite alternate;
  will-change: transform;
}
.glow-layer .g1 { width: 620px; height: 620px; top: -220px; right: -110px;
  background: radial-gradient(circle, rgba(200,160,90,.22) 0%, rgba(200,160,90,.10) 42%, transparent 70%); }
.glow-layer .g2 { width: 560px; height: 560px; bottom: -160px; left: -180px;
  background: radial-gradient(circle, rgba(157,179,163,.25) 0%, rgba(157,179,163,.11) 44%, transparent 72%);
  animation-delay: -8s; }
.glow-layer .g3 { width: 480px; height: 480px; top: 38%; right: -200px;
  background: radial-gradient(circle, rgba(201,139,122,.19) 0%, rgba(201,139,122,.08) 44%, transparent 72%);
  animation-delay: -16s; }

@keyframes drift {
  from { transform: translate3d(0,0,0) scale(1); }
  to   { transform: translate3d(18px,-24px,0) scale(1.12); }
}

/* ---------------------------- 通用 ---------------------------- */

.shell { width: 100%; max-width: 1060px; margin: 0 auto; padding: 0 24px; }
.main { flex: 1 0 auto; }

h1, h2, h3, h4 { font-family: var(--serif); font-weight: 600; line-height: 1.42; letter-spacing: .01em; }
a { color: inherit; text-decoration: none; }
img, svg { display: block; max-width: 100%; }
button { font: inherit; color: inherit; cursor: pointer; background: none; border: 0; }
input, textarea, select { font: inherit; color: inherit; }

.muted  { color: var(--ink-3); }
.dim    { color: var(--ink-2); }
.center { text-align: center; }
.mt-s { margin-top: 8px; }
.mt   { margin-top: 16px; }
.mt-l { margin-top: 32px; }
.hide { display: none !important; }

.eyebrow {
  display: inline-block;
  font-size: 12px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--ink-3);
}

/* 按钮 */
.btn-solid, .btn-line, .btn-quiet {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border-radius: 999px;
  padding: 13px 26px;
  font-size: 15px;
  transition: transform .28s var(--ease), box-shadow .28s var(--ease), background .2s, border-color .2s, opacity .2s;
  white-space: nowrap;
}
.btn-solid {
  background: var(--ink);
  color: #fdfaf4;
  box-shadow: 0 10px 24px -12px rgba(53,48,43,.55);
}
.btn-solid:hover { transform: translateY(-2px); box-shadow: 0 16px 32px -14px rgba(53,48,43,.5); }
.btn-solid:active { transform: translateY(0); }
.btn-line {
  border: 1px solid var(--line);
  background: rgba(255,255,255,.5);
  color: var(--ink);
}
.btn-line:hover { border-color: rgba(58,51,44,.24); background: #fff; transform: translateY(-1px); }
.btn-quiet { color: var(--ink-2); padding: 10px 16px; }
.btn-quiet:hover { color: var(--ink); }
.btn-sm { padding: 8px 18px; font-size: 14px; }
.btn-lg { padding: 16px 34px; font-size: 16px; }
.btn-block { width: 100%; }
.btn-solid[disabled], .btn-line[disabled] { opacity: .45; pointer-events: none; }
/* 未选选项时的「接着说」：不要变成一块死灰。
   换成暖灰 + 正常字色，读起来是「还差你一句话」，不是「坏了」 */
.btn-solid[disabled] {
  background: #ddd3c3;
  color: #6b625a;
  opacity: 1;
  box-shadow: none;
}
/* 未选选项时的「接着说」：不要变成一块死灰。
   换成暖灰 + 正常字色，读起来是「还差你一句话」，不是「坏了」 */
.btn-solid[disabled] {
  background: #ddd3c3;
  color: #6b625a;
  opacity: 1;
  box-shadow: none;
}

/* 卡片 */
.card {
  background: var(--card);
  border: 1px solid var(--line-2);
  border-radius: var(--r-lg);
  backdrop-filter: blur(12px) saturate(120%);
  -webkit-backdrop-filter: blur(12px) saturate(120%);
  box-shadow: var(--shadow);
}

/* 输入 */
.field { margin-bottom: 18px; }
.field label { display: block; font-size: 13px; color: var(--ink-2); margin-bottom: 7px; letter-spacing: .02em; }
.input {
  width: 100%;
  padding: 13px 16px;
  background: rgba(255,255,255,.72);
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  font-size: 15px;
  transition: border-color .2s, box-shadow .2s, background .2s;
}
.input:focus {
  outline: none;
  border-color: rgba(200,160,90,.6);
  background: #fff;
  box-shadow: 0 0 0 3px rgba(200,160,90,.13);
}
.input::placeholder { color: var(--ink-4); }

.alert {
  padding: 12px 16px;
  border-radius: var(--r-sm);
  font-size: 14px;
  background: rgba(201,139,122,.10);
  border: 1px solid rgba(201,139,122,.24);
  color: #8d5346;
}
.alert.ok { background: rgba(157,179,163,.14); border-color: rgba(157,179,163,.34); color: #4f6558; }

/* ---------------------------- 顶栏 ---------------------------- */

.topbar {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(250,246,239,.82);
  backdrop-filter: blur(16px) saturate(140%);
  -webkit-backdrop-filter: blur(16px) saturate(140%);
  border-bottom: 1px solid var(--line-2);
}
.topbar-inner {
  display: flex;
  align-items: center;
  gap: 28px;
  height: 66px;
}
.brand { display: flex; align-items: center; gap: 9px; flex-shrink: 0; }
.brand-mark { transition: transform .5s var(--ease); }
.brand:hover .brand-mark { transform: rotate(-8deg); }
.brand-word { font-family: var(--serif); font-size: 17px; letter-spacing: .04em; }

.nav { display: flex; gap: 4px; margin-right: auto; }
.nav a {
  position: relative;
  padding: 7px 14px;
  font-size: 14.5px;
  color: var(--ink-2);
  border-radius: 999px;
  transition: color .2s, background .2s;
}
.nav a:hover { color: var(--ink); background: rgba(58,51,44,.045); }
.nav a.active { color: var(--ink); font-weight: 500; }
.nav a.active::after {
  content: "";
  position: absolute;
  left: 50%; bottom: 1px;
  width: 14px; height: 2px;
  margin-left: -7px;
  border-radius: 2px;
  background: var(--grad);
}

.topbar-right { display: flex; align-items: center; gap: 10px; margin-left: auto; }
.me-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px 6px 10px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: rgba(255,255,255,.56);
  font-size: 14px;
  transition: border-color .2s, background .2s;
}
.me-chip:hover { border-color: rgba(58,51,44,.2); background: #fff; }
.me-dot { width: 7px; height: 7px; border-radius: 50%; background: var(--ink-4); }
.me-dot.is-pro { background: var(--gold); box-shadow: 0 0 0 3px rgba(200,160,90,.18); }
.me-name { max-width: 90px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

.menu-btn { display: none; width: 36px; height: 36px; border-radius: 10px; padding: 10px 8px; }
.menu-btn span { display: block; height: 1.5px; background: var(--ink); border-radius: 2px; }
.menu-btn span + span { margin-top: 6px; }

.mobile-nav {
  display: flex;
  flex-direction: column;
  padding: 6px 24px 16px;
  border-bottom: 1px solid var(--line-2);
  background: rgba(250,246,239,.96);
}
/* 关键：.mobile-nav 的 display:flex 会覆盖 hidden 属性的 UA 样式，必须显式关掉 */
.mobile-nav[hidden] { display: none; }
.mobile-nav a { padding: 12px 0; font-size: 15px; border-bottom: 1px solid var(--line-2); }
.mobile-nav a:last-child { border-bottom: 0; }

/* ---------------------------- 首页 ---------------------------- */

.hero {
  padding: 76px 0 48px;
  position: relative;
}
.hero-inner { max-width: 680px; }
.hero h1 {
  font-size: clamp(30px, 5.2vw, 50px);
  line-height: 1.32;
  letter-spacing: .01em;
}
.hero h1 .hl {
  /* 比 --grad 更深一档，保证浅底上的可读性 */
  background: linear-gradient(118deg, #b5674f 0%, #9d7526 52%, #5c8069 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  -webkit-text-fill-color: transparent;
}
.hero-sub {
  margin-top: 22px;
  font-size: 16.5px;
  color: var(--ink-2);
  line-height: 1.95;
  max-width: 560px;
}
.hero-acts { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 34px; }
.hero-meta {
  margin-top: 26px;
  font-size: 13.5px;
  color: var(--ink-3);
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
}
.hero-meta span { display: inline-flex; align-items: center; gap: 6px; }
.hero-meta i { width: 4px; height: 4px; border-radius: 50%; background: var(--ink-4); display: inline-block; }

.hero-quote {
  margin-top: 52px;
  padding: 26px 30px;
  border-left: 2px solid rgba(200,160,90,.5);
  font-family: var(--serif);
  font-size: 16.5px;
  line-height: 2;
  color: var(--ink-2);
}
.hero-quote span { display: block; margin-top: 10px; font-family: var(--sans); font-size: 13px; color: var(--ink-3); letter-spacing: .04em; }

/* 三栏说明 */
.flow { padding: 56px 0 20px; }
.flow-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-top: 30px;
}
.flow-card { padding: 26px 24px 28px; }
.flow-num {
  font-family: var(--serif);
  font-size: 13px;
  letter-spacing: .2em;
  color: var(--gold);
}
.flow-card h3 { font-size: 18px; margin: 12px 0 8px; }
.flow-card p { font-size: 14.5px; color: var(--ink-2); line-height: 1.85; }

/* 章节预览 */
.chapters-preview { padding: 56px 0; }
.ch-list { display: flex; flex-direction: column; gap: 2px; margin-top: 28px; }
.ch-row {
  display: flex;
  align-items: baseline;
  gap: 20px;
  padding: 20px 4px;
  border-bottom: 1px solid var(--line-2);
}
.ch-row:last-child { border-bottom: 0; }
.ch-idx { font-family: var(--serif); font-size: 13px; color: var(--ink-4); width: 30px; flex-shrink: 0; letter-spacing: .1em; }
.ch-name { font-family: var(--serif); font-size: 19px; width: 84px; flex-shrink: 0; }
.ch-sub { font-size: 14.5px; color: var(--ink-2); flex: 1; }
.ch-flag { font-size: 12.5px; color: var(--ink-4); flex: none; }
.ch-row:hover .ch-name { color: var(--clay); }

/* 未读的页：用色调和「未读」标记区分，不要整行压透明度。
   opacity:.42 叠在米色底上，正文对比度只剩 2:1，等于看不清——
   状态该由颜色和标记表达，不该拿可读性换。 */
.ch-row.is-unread .ch-name { color: var(--ink-2); }
.ch-row.is-unread .ch-sub  { color: var(--ink-3); }
.ch-row.is-unread:hover .ch-name { color: var(--ink); }

/* ---------------------------- 我的书 ---------------------------- */

.book-head { padding: 34px 32px; margin-bottom: 34px; }
.book-head-row { display: flex; gap: 28px; align-items: flex-start; flex-wrap: wrap; }
.book-head-main { flex: 1 1 300px; }
.book-head-side { flex: 0 0 auto; min-width: 180px; }
.book-head h1 { font-size: 28px; margin-top: 10px; }
.book-meta { font-size: 14.5px; }
.book-quote {
  font-family: var(--serif);
  font-size: 15px;
  line-height: 2;
  color: var(--ink-2);
  margin-top: 18px;
}
.book-acts { margin-top: 20px; display: flex; flex-direction: column; gap: 8px; }
.link-u { border-bottom: 1px solid currentColor; }

/* 小节标题压一档：书架页里用两次，别再写 font-size:22px 盖掉 clamp() */
.sec-head.is-sub { margin-top: 40px; margin-bottom: 22px; }
.sec-head.is-sub h2 { font-size: 22px; }
.sec-head.is-sub p  { font-size: 14px; margin-top: 8px; }

.empty-state { padding: 80px 0; }
.empty-state h1 { font-size: 26px; }

/* ---------------------------- 通用小件 ---------------------------- */
/* 这几个模式原先在四五个页面各写一遍内联样式，
   改一次要翻五处，而且没法跟着断点走。集中在这里。 */

.btn-row { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; }
.btn-row.is-left { justify-content: flex-start; }
.foot-note { font-size: 12.5px; color: var(--ink-4); }
.alert.is-stacked { margin-bottom: 20px; }
.alert.is-fine { font-size: 13px; line-height: 1.85; }
.h-sm { font-size: 22px; }
.h-md { font-size: 24px; }
.h-lg { font-size: 26px; }
.h-sub { font-size: 16px; }
.mono { font-family: ui-monospace, Menlo, Consolas, monospace; }
.mt-m { margin-top: 18px; }
/* 后台卡片：原来每张各写一个 padding（30/26/24），堆起来参差不齐 */
.card.is-pad { padding: 26px 28px; }

/* ---------------------------- 板块标题 ---------------------------- */

.sec-head { margin-bottom: 34px; }
.sec-head h2 { font-size: clamp(24px, 3.4vw, 32px); }
.sec-head p { margin-top: 12px; color: var(--ink-2); font-size: 15.5px; max-width: 560px; }

/* ---------------------------- 选人格 ---------------------------- */

.pick-wrap { padding: 54px 0 80px; }
.pick-head { text-align: center; max-width: 620px; margin: 0 auto 42px; }
.pick-head h1 { font-size: clamp(26px, 4.2vw, 38px); }
.pick-head p { margin-top: 16px; color: var(--ink-2); font-size: 15.5px; line-height: 1.9; }

.type-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
}
.type-cell {
  position: relative;
  padding: 20px 18px 18px;
  border-radius: var(--r);
  border: 1px solid var(--line-2);
  background: rgba(255,255,255,.5);
  text-align: left;
  transition: transform .32s var(--ease), border-color .24s, background .24s, box-shadow .32s var(--ease);
}
.type-cell:hover {
  transform: translateY(-3px);
  border-color: rgba(200,160,90,.42);
  background: #fff;
  box-shadow: var(--shadow);
}
.type-cell .tc-code {
  font-family: var(--serif);
  font-size: 19px;
  letter-spacing: .06em;
}
.type-cell .tc-nick {
  margin-top: 6px;
  font-size: 13.5px;
  color: var(--ink-2);
}
.type-cell .tc-title {
  margin-top: 3px;
  font-size: 12.5px;
  color: var(--ink-3);
  line-height: 1.6;
}
.type-cell::after {
  content: "";
  position: absolute;
  top: 14px; right: 14px;
  width: 5px; height: 5px;
  border-radius: 50%;
  background: var(--paper-3);
  transition: background .24s;
}
.type-cell:hover::after { background: var(--gold); }

/* 变体选择 */
.variant-box {
  margin-top: 40px;
  padding: 30px 28px;
  max-width: 620px;
  margin-left: auto;
  margin-right: auto;
}
.variant-box h3 { font-size: 18px; margin-bottom: 6px; }
.variant-box > p { font-size: 14px; color: var(--ink-3); margin-bottom: 22px; }
.variant-opts { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.variant-opt {
  display: block;
  padding: 18px 18px;
  border: 1px solid var(--line);
  border-radius: var(--r);
  background: rgba(255,255,255,.55);
  cursor: pointer;
  transition: border-color .22s, background .22s, transform .22s var(--ease);
}
.variant-opt:hover { border-color: rgba(200,160,90,.5); transform: translateY(-2px); }
.variant-opt input { position: absolute; opacity: 0; pointer-events: none; }
.variant-opt .vo-k { font-family: var(--serif); font-size: 20px; letter-spacing: .06em; }
.variant-opt .vo-n { font-size: 14px; margin-top: 4px; }
.variant-opt .vo-d { font-size: 12.5px; color: var(--ink-3); margin-top: 8px; line-height: 1.7; }
.variant-opt input:checked + .vo-k { color: var(--clay); }
.variant-opt:has(input:checked) {
  border-color: rgba(201,139,122,.55);
  background: #fff;
  box-shadow: 0 0 0 3px rgba(201,139,122,.10);
}

/* ---------------------------- 答题 ---------------------------- */

.take-wrap { padding: 34px 0 80px; }

/* 答题页：进度不做 sticky、不加底色，避免在暖纸背景上出现白色色带 */
/* 宽度必须和下面的卡片一致（660），否则 1280 下进度条比卡片各宽出 176px，
   一页里出现三种左边界，看着就是"没对齐" */
.progress {
  padding: 14px 0 10px;
  margin: 0 auto 6px;
  max-width: 660px;
}
.progress-bar {
  height: 3px;
  border-radius: 3px;
  background: rgba(58,51,44,.09);
  overflow: hidden;
}
.progress-bar i {
  display: block;
  height: 100%;
  width: 0;
  border-radius: 3px;
  background: var(--grad);
  transition: width .5s var(--ease);
}
.progress-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 10px;
  font-size: 12.5px;
  color: var(--ink-3);
  letter-spacing: .04em;
}
.progress-meta b { color: var(--ink-2); font-weight: 500; }

/* 第二章起给游客一个不打扰的「留个名字」提示条 */
.save-bar {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
  max-width: 660px;
  margin: 4px auto 0;
  padding: 12px 16px;
  border: 1px solid var(--line-2);
  border-radius: 12px;
  background: rgba(200,160,90,.06);
  font-size: 13px;
  color: var(--ink-2);
  line-height: 1.7;
}
.save-bar > span { flex: 1 1 220px; }
.save-bar .btn-line { flex: none; }

.q-stage { max-width: 660px; margin: 0 auto; padding-top: 14px; }
.q-step { display: none; }
.q-step.on { display: block; }

@keyframes rise {
  from { opacity: 0; transform: translateY(14px); }
  to   { opacity: 1; transform: translateY(0); }
}

.q-card { padding: 30px 36px 26px; }
.q-eyebrow {
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--ink-3);
  text-transform: uppercase;
}
.q-title {
  font-family: var(--serif);
  font-size: clamp(20px, 2.6vw, 24px);
  line-height: 1.55;
  margin: 12px 0 0;
  font-weight: 600;
}
.q-hint {
  margin-top: 10px;
  font-size: 13px;
  color: var(--ink-3);
  font-style: normal;
}
/* 追问不是「提示框」。它该像有人在你旁边低声补一句：
   衬线、斜体、一道很淡的竖线，不铺底色 —— 铺了底就成了输入框 */
.q-probe {
  margin-top: 10px;
  padding: 2px 0 2px 14px;
  border-left: 2px solid rgba(200,160,90,.28);
  background: none;
  font-family: var(--serif);
  font-size: 14.5px;
  font-style: italic;
  color: #8a7a63;
  line-height: 1.75;
}

.opts { margin-top: 20px; display: flex; flex-direction: column; gap: 8px; }
.opt {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 13px 16px;
  border: 1px solid var(--line);
  border-radius: var(--r);
  background: rgba(255,255,255,.5);
  cursor: pointer;
  transition: border-color .22s, background .22s, transform .22s var(--ease), box-shadow .22s;
}
.opt:hover { border-color: rgba(200,160,90,.5); background: #fff; transform: translateX(3px); }
.opt input { position: absolute; opacity: 0; pointer-events: none; }
/* 选项左边不放单选圈。一个圆圈加一个圆角框，读起来就是「问卷」；
   换成「一 二 三 四」，读起来像书里的几条路，选哪条都合理 */
.opt-idx {
  flex: none;
  width: 1.15em;
  padding-top: 3px;
  font-family: var(--serif);
  font-size: 12.5px;
  line-height: 1;
  color: var(--ink-4);
  letter-spacing: .02em;
  transition: color .22s;
}
.opt-text { font-size: 15px; line-height: 1.65; }
.opt:has(input:checked) {
  border-color: rgba(201,139,122,.6);
  background: #fff;
  box-shadow: 0 0 0 3px rgba(201,139,122,.09);
}
.opt:has(input:checked) .opt-idx { color: var(--clay); }
.opt:has(input:checked) .opt-text { color: var(--ink); }

.q-acts {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  margin-top: 22px;
  padding-top: 22px;
  border-top: 1px solid var(--line-2);
}
.q-acts .grow { flex: 1; }

.skip-link {
  font-size: 13px;
  color: var(--ink-3);
  border-bottom: 1px dashed var(--line);
  padding-bottom: 1px;
  transition: color .2s;
}
.skip-link:hover { color: var(--ink-2); }

/* 章节过场 */
.ch-inter {
  max-width: 620px;
  margin: 0 auto;
  padding: 48px 40px 44px;
  text-align: center;
  animation: rise .6s var(--ease) both;
}
.ch-inter .ci-num {
  font-family: var(--serif);
  font-size: 13px;
  letter-spacing: .3em;
  color: var(--gold);
}
.ch-inter h2 { font-size: clamp(26px, 4vw, 34px); margin: 18px 0 0; }
.ch-inter .ci-sub { margin-top: 12px; font-size: 14.5px; color: var(--ink-3); }
.ch-inter .ci-lead {
  margin-top: 30px;
  font-family: var(--serif);
  font-size: 16.5px;
  line-height: 2.1;
  color: var(--ink-2);
}

/* ---------------------------- 书页 ---------------------------- */

.book-wrap { padding: 40px 0 90px; }

.book-page {
  position: relative;
  max-width: 640px;
  margin: 0 auto;
  padding: 64px 56px 56px;
  background: var(--card-solid);
  border: 1px solid rgba(58,51,44,.09);
  border-radius: 6px;
  box-shadow:
    0 1px 2px rgba(58,51,44,.04),
    0 24px 60px -28px rgba(58,51,44,.24),
    inset 0 0 60px rgba(243,236,225,.55);
}
.book-page::before {
  /* 书脊阴影 */
  content: "";
  position: absolute;
  top: 0; bottom: 0; left: 0;
  width: 26px;
  background: linear-gradient(90deg, rgba(58,51,44,.055), transparent);
  border-radius: 6px 0 0 6px;
  pointer-events: none;
}
.bp-chapter {
  font-family: var(--serif);
  font-size: 12px;
  letter-spacing: .32em;
  color: var(--gold);
  text-align: center;
}
.bp-title {
  font-family: var(--serif);
  font-size: clamp(22px, 3.4vw, 29px);
  text-align: center;
  margin: 16px 0 0;
  line-height: 1.55;
}
.bp-rule {
  width: 34px;
  height: 1px;
  margin: 26px auto 34px;
  background: var(--line);
}
.bp-body { font-family: var(--serif); font-size: 16.5px; line-height: 2.15; color: #453f38; }
.bp-block + .bp-block { margin-top: 26px; }
.bp-label {
  display: block;
  font-family: var(--sans);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--ink-3);
  margin-bottom: 8px;
}
.bp-lead { font-size: 15.5px; color: var(--ink-2); }
.bp-quote {
  margin: 0;
  padding-left: 18px;
  border-left: 1.5px solid rgba(200,160,90,.45);
  font-style: normal;
  color: #5c5348;
}
.bp-soft {
  padding: 16px 20px;
  background: rgba(157,179,163,.10);
  border-radius: var(--r-sm);
  font-size: 15px;
  color: #4f6558;
  font-family: var(--sans);
  line-height: 1.9;
}
.bp-practice {
  padding: 20px 22px;
  background: rgba(200,160,90,.08);
  border-radius: var(--r-sm);
  border: 1px dashed rgba(200,160,90,.36);
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.9;
  color: #6d5a34;
}
.bp-close {
  margin-top: 34px;
  padding-top: 26px;
  border-top: 1px solid var(--line-2);
  font-family: var(--sans);
  font-size: 14.5px;
  color: var(--ink-3);
  text-align: center;
  line-height: 1.95;
}
.bp-ending {
  text-align: center;
  font-size: 16px;
  line-height: 2.1;
  padding: 10px 0;
}
.bp-spine {
  text-align: center;
  padding: 22px 0 4px;
}
.bp-spine .sp-code {
  font-family: var(--serif);
  font-size: 30px;
  letter-spacing: .16em;
}
.bp-spine .sp-title { font-size: 13.5px; color: var(--ink-3); margin-top: 8px; }
.bp-page-num {
  margin-top: 36px;
  text-align: center;
  font-family: var(--serif);
  font-size: 12px;
  color: var(--ink-4);
  letter-spacing: .2em;
}

.book-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-top: 34px;
  flex-wrap: wrap;
}

/* 书架 */
.shelf { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 16px; }
.shelf-item {
  display: block;
  padding: 22px 20px;
  border-radius: var(--r);
  border: 1px solid var(--line-2);
  background: rgba(255,255,255,.5);
  transition: transform .3s var(--ease), box-shadow .3s var(--ease), border-color .2s;
}
.shelf-item:hover { transform: translateY(-3px); box-shadow: var(--shadow); border-color: rgba(200,160,90,.4); background: #fff; }
.shelf-item .si-code { font-family: var(--serif); font-size: 16px; letter-spacing: .1em; }
.shelf-item .si-title { font-size: 13.5px; color: var(--ink-2); margin-top: 6px; }
.shelf-item .si-meta { font-size: 12px; color: var(--ink-4); margin-top: 14px; letter-spacing: .04em; }

/* ---------------------------- 书灵对话 ---------------------------- */

.spirit-wrap { padding: 34px 0 60px; }
.chat-shell {
  max-width: 720px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  height: calc(100vh - 66px - 140px);
  min-height: 460px;
}
.chat-head {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 16px 4px 18px;
  border-bottom: 1px solid var(--line-2);
  /* 窄屏放不下时让徽标/按钮整体换行，
     否则「读过你《INFP·动荡型》的那本」会被挤成四行 */
  flex-wrap: wrap;
  row-gap: 10px;
}
.chat-head-main { flex: 1 1 170px; min-width: 170px; }
.chat-avatar {
  width: 42px; height: 42px;
  border-radius: 50%;
  background: var(--grad-soft);
  border: 1px solid var(--line);
  display: grid;
  place-items: center;
  font-family: var(--serif);
  font-size: 15px;
  color: var(--ink-2);
  flex-shrink: 0;
}
.chat-who { font-family: var(--serif); font-size: 16px; }
.chat-sub { font-size: 12.5px; color: var(--ink-3); margin-top: 2px; }
.chat-badge {
  margin-left: auto;
  font-size: 11.5px;
  padding: 4px 10px;
  border-radius: 999px;
  border: 1px solid var(--line);
  color: var(--ink-3);
  white-space: nowrap;
}
.chat-badge.is-pro { border-color: rgba(200,160,90,.4); color: #8a6a2c; background: rgba(200,160,90,.08); }

.chat-log {
  flex: 1;
  overflow-y: auto;
  padding: 26px 4px 10px;
  display: flex;
  flex-direction: column;
  gap: 18px;
  scrollbar-width: thin;
  scrollbar-color: var(--paper-3) transparent;
}
.chat-log::-webkit-scrollbar { width: 6px; }
.chat-log::-webkit-scrollbar-thumb { background: var(--paper-3); border-radius: 6px; }

.msg { display: flex; }
.msg.user { justify-content: flex-end; }
.msg-body {
  max-width: 78%;
  padding: 14px 18px;
  border-radius: 16px;
  font-size: 15px;
  line-height: 1.85;
  white-space: pre-wrap;
  word-break: break-word;
}
.msg.spirit .msg-body {
  background: rgba(255,255,255,.78);
  border: 1px solid var(--line-2);
  border-bottom-left-radius: 6px;
  font-family: var(--serif);
  font-size: 15.5px;
  color: #453f38;
}
.msg.user .msg-body {
  background: var(--ink);
  color: #f7f2e9;
  border-bottom-right-radius: 6px;
}
.msg-spirit-intro {
  font-size: 13px;
  color: var(--ink-3);
  padding: 2px 4px 0;
}

.typing { display: inline-flex; gap: 4px; align-items: center; }
.typing i {
  width: 5px; height: 5px;
  border-radius: 50%;
  background: var(--ink-4);
  animation: blink 1.3s infinite;
}
.typing i:nth-child(2) { animation-delay: .18s; }
.typing i:nth-child(3) { animation-delay: .36s; }
@keyframes blink { 0%,60%,100% { opacity: .28; } 30% { opacity: 1; } }

.chat-quick {
  display: flex;
  flex-wrap: wrap;
  gap: 7px 8px;
  padding: 12px 4px 4px;
}
.quick-chip {
  flex: 0 0 auto;
  padding: 7px 14px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: rgba(255,255,255,.6);
  font-size: 13.5px;
  color: var(--ink-2);
  transition: border-color .2s, background .2s, color .2s;
}
.quick-chip:hover { border-color: rgba(200,160,90,.5); background: #fff; color: var(--ink); }

.chat-input-row {
  display: flex;
  align-items: flex-end;
  gap: 10px;
  padding: 12px 0 0;
  border-top: 1px solid var(--line-2);
  margin-top: 8px;
}
.chat-input {
  flex: 1;
  resize: none;
  max-height: 132px;
  min-height: 46px;
  padding: 13px 16px;
  border-radius: 14px;
  border: 1px solid var(--line);
  background: rgba(255,255,255,.78);
  font-size: 15px;
  line-height: 1.6;
  transition: border-color .2s, box-shadow .2s;
}
.chat-input:focus { outline: none; border-color: rgba(200,160,90,.55); box-shadow: 0 0 0 3px rgba(200,160,90,.1); }
.send-btn {
  width: 46px; height: 46px;
  flex-shrink: 0;
  border-radius: 50%;
  background: var(--ink);
  color: #fdfaf4;
  display: grid;
  place-items: center;
  transition: transform .24s var(--ease), opacity .2s;
}
.send-btn:hover { transform: translateY(-2px) scale(1.03); }
.send-btn[disabled] { opacity: .4; pointer-events: none; }

.chat-gate {
  padding: 24px;
  text-align: center;
  border-radius: var(--r);
  background: rgba(200,160,90,.07);
  border: 1px dashed rgba(200,160,90,.4);
  margin-top: 14px;
}
.chat-gate p { font-size: 14px; color: #6d5a34; line-height: 1.85; }
.chat-gate .gate-acts { display: flex; gap: 10px; justify-content: center; margin-top: 16px; flex-wrap: wrap; }

/* ---------------------------- 表单页 ---------------------------- */

.auth-wrap { padding: 70px 0 100px; }
.auth-card { max-width: 430px; margin: 0 auto; padding: 42px 40px 36px; }
.auth-card h1 { font-size: 25px; margin-bottom: 8px; }
.auth-card .sub { font-size: 14px; color: var(--ink-3); margin-bottom: 28px; }
.auth-foot { margin-top: 22px; font-size: 13.5px; color: var(--ink-3); text-align: center; }
.auth-foot a { color: var(--ink-2); border-bottom: 1px solid var(--line); }

/* ---------------------------- 会员 ---------------------------- */

.pro-wrap { padding: 60px 0 90px; }
.pro-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; margin-top: 30px; }
.plan { padding: 32px 30px 34px; position: relative; }
.plan.is-feature {
  border-color: rgba(200,160,90,.42);
  background: linear-gradient(160deg, rgba(255,253,248,.9), rgba(250,244,232,.86));
}
.plan-tag {
  position: absolute;
  top: 20px; right: 22px;
  font-size: 11.5px;
  letter-spacing: .1em;
  color: #8a6a2c;
  background: rgba(200,160,90,.14);
  border-radius: 999px;
  padding: 3px 10px;
}
.plan h3 { font-size: 20px; }
.plan .plan-price { font-family: var(--serif); font-size: 30px; margin: 16px 0 6px; }
.plan .plan-price small { font-family: var(--sans); font-size: 13px; color: var(--ink-3); margin-left: 4px; }
.plan ul { list-style: none; margin-top: 22px; display: flex; flex-direction: column; gap: 11px; }
.plan li { font-size: 14.5px; color: var(--ink-2); padding-left: 22px; position: relative; line-height: 1.7; }
.plan li::before {
  content: "";
  position: absolute;
  left: 4px; top: 8px;
  width: 7px; height: 7px;
  border-radius: 50%;
  background: rgba(157,179,163,.9);
}
.plan li.no::before { background: var(--paper-3); }
.plan li.no { color: var(--ink-4); }

.activate-box { max-width: 520px; margin: 40px auto 0; padding: 32px 30px; }
.activate-box h3 { font-size: 18px; margin-bottom: 8px; }
.activate-box p { font-size: 13.5px; color: var(--ink-3); margin-bottom: 20px; }
.code-input {
  width: 100%;
  text-align: center;
  font-family: var(--serif);
  font-size: 20px;
  letter-spacing: .16em;
  padding: 16px;
  border-radius: var(--r-sm);
  border: 1px solid var(--line);
  background: rgba(255,255,255,.8);
  text-transform: uppercase;
}
.code-input:focus { outline: none; border-color: rgba(200,160,90,.6); box-shadow: 0 0 0 3px rgba(200,160,90,.12); }

/* 档案信息 */
.kv-list { display: flex; flex-direction: column; gap: 1px; }
.kv {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding: 14px 2px;
  border-bottom: 1px solid var(--line-2);
  font-size: 14.5px;
}
.kv:last-child { border-bottom: 0; }
.kv .k { color: var(--ink-3); }
.kv .v { color: var(--ink); text-align: right; }

/* ---------------------------- 页脚 ---------------------------- */

.foot {
  margin-top: auto;
  background: rgba(243,236,225,.6);
  border-top: 1px solid var(--line-2);
  padding: 52px 0 26px;
}
.foot-main { display: flex; gap: 60px; flex-wrap: wrap; }
.foot-brand { flex: 1 1 240px; }
.foot-title { font-family: var(--serif); font-size: 17px; letter-spacing: .04em; }
.foot-say { margin-top: 10px; font-size: 13.5px; color: var(--ink-3); line-height: 1.85; max-width: 280px; }
.foot-cols { display: flex; gap: 54px; flex-wrap: wrap; }
.foot-col { min-width: 130px; }
.foot-col h4 { font-family: var(--sans); font-size: 12px; letter-spacing: .14em; color: var(--ink-3); margin-bottom: 14px; text-transform: uppercase; }
.foot-col a { display: block; font-size: 13.5px; color: var(--ink-2); padding: 5px 0; transition: color .2s; }
.foot-col a:hover { color: var(--ink); }
.foot-note { font-size: 12.5px; color: var(--ink-3); line-height: 1.85; max-width: 240px; }
.foot-bottom {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  margin-top: 46px;
  padding-top: 22px;
  border-top: 1px solid var(--line-2);
  font-size: 12.5px;
  color: var(--ink-4);
}
.foot-bottom a { color: var(--ink-3); border-bottom: 1px solid var(--line); }

/* ---------------------------- 响应式 ---------------------------- */

@media (max-width: 900px) {
  .flow-grid { grid-template-columns: 1fr; }
  .type-grid { grid-template-columns: repeat(3, 1fr); }
  .pro-grid { grid-template-columns: 1fr; }
  .hero { padding: 56px 0 36px; }
  .hero-quote { margin-top: 40px; padding: 22px 22px; font-size: 15.5px; }
}

@media (max-width: 760px) {
  .nav { display: none; }
  .menu-btn { display: block; }
  .topbar-right .btn-line { display: none; }
  .shell { padding: 0 18px; }
  .type-grid { grid-template-columns: repeat(2, 1fr); gap: 10px; }
  .type-cell { padding: 16px 14px 14px; }
  .type-cell .tc-code { font-size: 17px; }
  .type-cell .tc-title { display: none; }
  .q-card { padding: 28px 22px 24px; }
  .ch-inter { padding: 36px 24px 32px; }
  .book-page { padding: 44px 26px 40px; margin: 0 -2px; }
  .book-page::before { width: 16px; }
  .bp-body { font-size: 15.5px; line-height: 2.05; }
  .variant-opts { grid-template-columns: 1fr; }
  .chat-shell { height: calc(100vh - 66px - 108px); }
  .msg-body { max-width: 86%; font-size: 14.5px; }
  .foot-cols { gap: 30px; }
  .foot-main { gap: 34px; }
  .auth-card { padding: 34px 24px 28px; }
  .q-acts { flex-wrap: wrap; }
  .q-acts .btn-solid { flex: 1; }
}

@media (max-width: 420px) {
  .type-grid { grid-template-columns: repeat(2, 1fr); }
  .hero h1 { font-size: 27px; }
  .hero-acts .btn-solid, .hero-acts .btn-line { width: 100%; }
}

/* 动效降级 */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
}

/* 打印（书页可以打印出来） */
@media print {
  .topbar, .foot, .book-nav, .glow-layer, .paper-tex, .progress { display: none !important; }
  body { background: #fff; }
  .book-page { box-shadow: none; border: 0; max-width: 100%; padding: 0; }
}

/* 答题与对话页：专注模式，收起页脚 */
.page-take .foot, .page-spirit .foot { display: none; }
.page-take .main, .page-spirit .main { min-height: calc(100vh - 66px); }

/* 账号条：书架页底部 */
.acct-bar {
  display: flex; align-items: center; gap: 18px; flex-wrap: wrap;
  margin-top: 64px; padding-top: 22px;
  border-top: 1px solid var(--line);
  font-size: 13px; color: var(--ink-3);
}
.acct-who { display: inline-flex; align-items: center; gap: 8px; margin-right: auto; color: var(--ink-2); }
.acct-tag {
  font-size: 11px; padding: 2px 7px; border-radius: 20px;
  background: rgba(200,160,90,.16); color: #8a6b2f;
}
.acct-bar a { color: var(--ink-3); }
.acct-bar a:hover { color: var(--ink); }
.foot-ver { color: var(--ink-4); font-size: 11.5px; letter-spacing: .03em; }

/* 备份邮箱：跟账号条同一条视觉线索，但单独成行，免得挤 */
.mail-row {
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
  margin-top: 18px; padding: 14px 16px;
  border: 1px solid var(--line-2); border-radius: var(--r);
  background: rgba(200,160,90,.045);
  font-size: 13px; color: var(--ink-3);
}
.mail-row label { flex: none; color: var(--ink-2); font-size: 12.5px; letter-spacing: .04em; }
.mail-row .input {
  flex: 1 1 240px; min-width: 0;
  padding: 8px 12px; font-size: 13.5px;
  border-radius: 9px;
}
.mail-row .btn-sm { flex: none; }
.mail-hint { flex: 1 1 100%; font-size: 12px; color: var(--ink-4); line-height: 1.7; }

/* =========================================================================
   动效系统 v1.4
   —— 只在 <html class="has-motion"> 时启用初始隐藏。
   若 JS 没跑起来（或用户开了「减少动态」），这个 class 不会存在，
   页面就是一张静态的、完整的纸，不会留下一堆看不见的空位。
   ========================================================================= */

/* 首屏开场：两片纸从中间裂开 */
.hero-open { display: none; }
.has-motion .hero-open {
  display: block;
  position: fixed;
  inset: 0;
  z-index: 90;
  pointer-events: none;   /* 动画期间也能点按钮，不挡交互 */
  background: transparent; /* 遮罩本身不能有底色：纸分开后要立刻看得见页面 */
}
.ho-pane {
  position: absolute;
  top: 0; bottom: 0; width: 50%;
  /* 先给一个不透明的底色，再叠渐变：
     只有渐变时，某些合成层在动画首帧会「透」出下面的正文 */
  background-color: #fbf6ed;
  background-image: linear-gradient(180deg, #fdfaf4 0%, #f6efe2 100%);
  will-change: transform;
}
/* 阴影只留在纸的内侧一边、且压得很淡。
   原来 30px 模糊 + .30 浓度，纸快滑干净时会在屏幕两边留下两条发雾的带子，
   看着像截图脏了。纸离开的过程要干净，重点在纸不在影子。 */
.ho-pane.ho-l { left: 0;  transform-origin: 100% 50%; box-shadow: 12px 0 26px -14px rgba(58,51,44,.22); }
.ho-pane.ho-r { right: 0; transform-origin: 0% 50%;  box-shadow: -12px 0 26px -14px rgba(58,51,44,.22); }
/* 内缘那道 1px 亮边：纸是有厚度的，切边不该是一块糊掉的渐变 */
.ho-pane::before {
  content: "";
  position: absolute;
  top: 0; bottom: 0; width: 1px;
  background: rgba(255, 253, 248, .95);
}
.ho-pane.ho-l::before { right: 0; }
.ho-pane.ho-r::before { left: 0; }
/* 中缝处的柔和折痕：不是一根线，是纸弯过去的那点暗 */
.ho-pane::after {
  content: "";
  position: absolute;
  top: 0; bottom: 0;
  width: 46px;
  pointer-events: none;
}
.ho-pane.ho-l::after { right: 0; background: linear-gradient(to right, transparent, rgba(58,51,44,.055)); }
.ho-pane.ho-r::after { left: 0;  background: linear-gradient(to left,  transparent, rgba(58,51,44,.055)); }

.ho-mark {
  position: absolute;
  left: 50%; top: 50%;
  transform: translate(-50%, -50%);
  font-family: var(--serif);
  font-size: 12.5px;
  letter-spacing: .42em;
  text-indent: .42em;
  color: var(--ink-3);
  opacity: 0;
  white-space: nowrap;
}

/* 标题遮罩：外层裁切，内层上移 —— 这才是「揭开」，不是淡入 */
.line { display: block; overflow: hidden; }
/* 内层必须是块级。它是 <span>，默认 inline，而 transform 对非替换的 inline 盒不生效：
   浏览器会把 translate(0,116%) 直接算成 0，只剩 scaleY —— 字不隐藏，只被拉长一点。
   这种 bug 看起来「动画没反应」，但动画其实一直在跑。 */
.mo-line { display: block; transform-origin: 50% 100%; }

/* 初始隐藏只给透明度，不给任何位移。
   踩过两次坑：① 它是 <span>，默认 inline，transform 对 inline 盒不生效；
   ② 改用 translate 属性也没用 —— GSAP 会把 CSS 的 translate 折进自己的 y 分量，
      动画跑到 yPercent:0 时那个 76px 还留在 y 里，字被遮罩裁掉一截，永远不归位。
   结论：位移一律由 GSAP 显式给（fromTo 写死起始值），CSS 只负责「别漏字」。 */
.has-motion .mo-line { opacity: 0; }
.has-motion .mo-el   { opacity: 0; translate: 0 30px; }
.has-motion .mo-fade { opacity: 0; }

/* 首屏右侧：一叠纸。没有图片，用纸本身当视觉 */
.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 60px;
  align-items: center;
}
.hero-visual {
  position: relative;
  height: 400px;
  perspective: 900px;
}
.bs { position: absolute; inset: 0; transform-style: preserve-3d; }
.bs-sheet {
  position: absolute;
  left: 50%; top: 50%;
  width: 236px; height: 318px;
  margin: -159px 0 0 -118px;
  background: var(--card-solid);
  border: 1px solid rgba(58,51,44,.10);
  border-radius: 3px;
  box-shadow: 0 20px 50px -28px rgba(58,51,44,.42), 0 2px 6px rgba(58,51,44,.05);
  will-change: transform;
}
.bs-sheet::after {          /* 纸面上的横线，让「纸」有内容而不空 */
  content: "";
  position: absolute;
  inset: 34px 26px;
  background-image: repeating-linear-gradient(
    to bottom,
    rgba(58,51,44,.10) 0 1px,
    transparent 1px 17px
  );
  opacity: .55;
  -webkit-mask-image: linear-gradient(180deg, #000 0%, #000 62%, transparent 100%);
          mask-image: linear-gradient(180deg, #000 0%, #000 62%, transparent 100%);
}
/* 静态状态下也是「散开的一叠」：
   用户开了减少动态、或 JS 没跑起来时，看到的该是成品，不是一张压扁的纸 */
.bs-sheet:nth-child(1) { transform: translate(-22px, -8px) rotate(-14deg); }
.bs-sheet:nth-child(2) { transform: translate(-8px, -3px) rotate(-7deg); }
.bs-sheet:nth-child(3) { transform: translate(7px, 2px)  rotate(0deg); }
.bs-sheet:nth-child(4) { transform: translate(21px, 7px) rotate(7deg); }
/* 静态状态下也是「散开的一叠」：
   用户开了减少动态、或 JS 没跑起来时，看到的该是成品，不是一张压扁的纸 */
.bs-sheet:nth-child(1) { transform: translate(-22px, -8px) rotate(-14deg); }
.bs-sheet:nth-child(2) { transform: translate(-8px, -3px) rotate(-7deg); }
.bs-sheet:nth-child(3) { transform: translate(7px, 2px)  rotate(0deg); }
.bs-sheet:nth-child(4) { transform: translate(21px, 7px) rotate(7deg); }
.bs-sheet.is-back { background: #f7f1e6; }
.bs-sheet.is-back::after { opacity: .3; }
.bs-ribbon {
  position: absolute;
  left: 50%; top: 50%;
  width: 14px; height: 78px;
  margin: -6px 0 0 62px;
  background: linear-gradient(180deg, #c98b7a, #b5674f);
  border-radius: 2px 2px 0 0;
  box-shadow: 0 8px 18px -10px rgba(181,103,79,.7);
  transform-origin: 50% 0;
  will-change: transform;
}
.bs-ribbon::after {
  content: "";
  position: absolute;
  left: 0; bottom: -7px;
  border-left: 7px solid transparent;
  border-right: 7px solid transparent;
  border-top: 8px solid #b5674f;
}

/* 1024 上下：右栏收窄一档，别让纸堆贴到屏幕边 */
@media (max-width: 1120px) and (min-width: 961px) {
  .hero-grid { grid-template-columns: minmax(0, 1fr) 250px; gap: 40px; }
  .bs-sheet { width: 206px; height: 278px; margin: -139px 0 0 -103px; }
  .bs-ribbon { margin: -4px 0 0 52px; height: 66px; }
}

/* 1024 上下：右栏收窄一档，别让纸堆贴到屏幕边 */
@media (max-width: 1120px) and (min-width: 961px) {
  .hero-grid { grid-template-columns: minmax(0, 1fr) 250px; gap: 40px; }
  .bs-sheet { width: 206px; height: 278px; margin: -139px 0 0 -103px; }
  .bs-ribbon { margin: -4px 0 0 52px; height: 66px; }
}

@media (max-width: 960px) {
  .hero-grid { grid-template-columns: 1fr; gap: 34px; }
  .hero-visual { height: 250px; order: 2; }
  .bs-sheet { width: 176px; height: 236px; margin: -118px 0 0 -88px; }
  .bs-ribbon { margin: -4px 0 0 44px; height: 60px; }
}

/* 章节预览的一行：进入时让分隔线自己长出来 */
.ch-row { position: relative; }
.ch-row::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: -1px;
  height: 1px;
  background: var(--line-2);
  transform: scaleX(0);
  transform-origin: 0 50%;
}
.has-motion .ch-row { border-bottom-color: transparent; }   /* 下划线交给 ::after 去「长」，别叠两条 */
.has-motion .ch-row::after { transform: scaleX(0); }
.has-motion .ch-row.mo-in::after {
  transition: transform .9s var(--ease) .1s;
  transform: scaleX(1);
}
.has-motion .ch-row:last-child::after { display: none; }

/* 答题卡：进出用 transform，不改布局，不引起重排 */
.q-step .q-card { will-change: transform, opacity; }
.has-motion .q-step.on { animation: none; }   /* 交给 GSAP，别和 CSS 动画抢 */

/* 选项：进入时错开一点，别整块砸下来 */
.q-opt-line {
  position: absolute;
  left: 0; top: 10px; bottom: 10px;
  width: 2px;
  background: var(--clay);
  border-radius: 2px;
  transform: scaleY(0);
  transition: transform .32s var(--ease);
}
.opt { position: relative; }
.opt:hover .q-opt-line,
.opt:has(input:checked) .q-opt-line { transform: scaleY(1); }

/* 柔和一点的按钮反馈：不要弹，只压一下 */
.btn-solid { will-change: transform; }

/* 尊重系统设置：全关 */
@media (prefers-reduced-motion: reduce) {
  .has-motion .mo-line,
  .has-motion .mo-el,
  .has-motion .mo-fade { transform: none !important; translate: none !important; scale: none !important; opacity: 1 !important; }
  .has-motion .hero-open { display: none !important; }
  .has-motion .ch-row::after { transform: scaleX(1); }
  html { scroll-behavior: auto; }
}

/* 题号：左边「第 3 题」，右边「共 10 题」。中间留空，
   比「3 / 10」更像有人在你旁边翻页，而不是系统在计数 */
.q-eyebrow { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; }
.q-eyebrow .q-of { font-size: 11.5px; letter-spacing: .1em; color: var(--ink-4); }

/* 过场与章末的一句安抚：比正文小、比注释大，不抢戏 */
.ci-note {
  margin-top: 18px;
  font-size: 13.5px;
  color: var(--ink-3);
  line-height: 1.9;
}