/* 第一版主 mmspok.cn · 蓝橙×纸白×墨 */
:root {
  --ink: #1b2430;
  --blue: #5a7fb2;
  --blue-dark: #46688f;
  --orange: #c96a28;
  --orange-dark: #b25a1d;
  --paper: #ffffff;
  --mist: #f2f4f7;
  --line: #dfe3ea;
  --gray: #67707e;
  --gray-l: #8b93a1;
  --text: #414a58;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; }
[id] { scroll-margin-top: 84px; }
.wrap { max-width: 1180px; margin: 0 auto; padding: 0 24px; }
.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

/* ===== 入场动画 ===== */
.rv { opacity: 0; transform: translateY(20px); transition: opacity .6s ease, transform .6s ease; }
.rv.in { opacity: 1; transform: none; }

/* ===== 按钮 ===== */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  border-radius: 8px; font-weight: 700; text-decoration: none; cursor: pointer;
  border: 2px solid transparent; transition: background .2s ease, color .2s ease;
}
.btn-pri { background: var(--orange); color: #fff; border-color: var(--orange); }
.btn-pri:hover { background: var(--orange-dark); border-color: var(--orange-dark); }
.btn-line { border-color: var(--ink); color: var(--ink); background: var(--paper); }
.btn-line:hover { background: var(--ink); color: #fff; }
.btn-lg { padding: 14px 34px; font-size: 16px; }

/* ===== 顶栏 ===== */
.hd { position: sticky; top: 0; z-index: 50; background: var(--paper); border-bottom: 2px solid var(--ink); }
.hd-in { display: flex; align-items: center; gap: 28px; height: 68px; }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--ink); }
.brand img { width: 40px; height: 40px; border-radius: 8px; box-shadow: 0 3px 6px rgba(27,36,48,.2); }
.brand-t strong { display: block; font-size: 17px; letter-spacing: .04em; line-height: 1.3; }
.brand-t small { display: block; font-size: 11px; color: var(--gray); line-height: 1.3; }
.nav { display: flex; gap: 22px; margin-left: auto; }
.nav a {
  font-size: 14px; color: var(--text); text-decoration: none;
  padding: 6px 2px; border-bottom: 2px solid transparent;
}
.nav a.on, .nav a:hover { color: var(--blue-dark); border-bottom-color: var(--blue); }
.hd-r { display: flex; align-items: center; gap: 14px; }
.hd-cta { padding: 9px 20px; font-size: 14px; box-shadow: 0 3px 5px rgba(201,106,40,.35); }
.burger {
  display: none; width: 42px; height: 38px; border: 2px solid var(--ink);
  background: var(--paper); border-radius: 8px; cursor: pointer; position: relative;
}
.burger span { position: absolute; left: 9px; right: 9px; height: 2px; background: var(--ink); }
.burger span:nth-child(1) { top: 11px; }
.burger span:nth-child(2) { top: 17px; }
.burger span:nth-child(3) { top: 23px; }

/* ===== 英雄区 ===== */
.hero { padding: 64px 0 72px; background: var(--paper); position: relative; overflow: hidden; }
.hero-in { display: flex; align-items: center; gap: 48px; }
.hero-l { flex: 1 1 52%; min-width: 0; }
.kick {
  font-size: 13px; letter-spacing: .22em; font-weight: 700;
  color: var(--ink); display: flex; align-items: center; margin: 0;
}
.kick i { font-style: normal; background: var(--blue); color: #fff; padding: 3px 9px; margin-right: 12px; font-size: 12px; letter-spacing: .1em; }
.hero h1 { font-size: 44px; margin: 18px 0 0; letter-spacing: .06em; line-height: 1.2; }
.hero h1::after { content: ''; display: block; width: 72px; height: 8px; background: var(--orange); margin-top: 14px; }
.lead { margin: 20px 0 0; color: var(--text); line-height: 1.9; font-size: 15.5px; }
.hero-acts { display: flex; gap: 14px; margin-top: 28px; flex-wrap: wrap; }
.hero-points { display: flex; margin: 26px 0 0; list-style: none; padding: 0; flex-wrap: wrap; }
.hero-points li { font-size: 13.5px; color: #4d5666; padding: 0 16px; border-left: 2px solid var(--line); }
.hero-points li:first-child { padding-left: 0; border-left: 0; }
.hero-r { flex: 0 0 440px; }

/* 书架陈列 */
.shelf { position: relative; width: 440px; height: 560px; box-shadow: 22px 26px 0 rgba(90,127,178,.16); }
.sh-plank { position: absolute; left: -6%; right: -6%; bottom: 24px; height: 16px; background: var(--ink); }
.sh-plank::after { content: ''; position: absolute; left: 0; right: 0; top: -5px; height: 5px; background: var(--blue); }
.sh-end { position: absolute; left: 0; bottom: 40px; width: 28px; height: 200px; background: var(--orange); }
.sh-end::before { content: ''; position: absolute; left: 14px; bottom: 0; width: 52px; height: 16px; background: var(--orange); }
.sh-book { position: absolute; margin: 0; bottom: 40px; background: var(--paper); border: 5px solid #fff; outline: 2px solid rgba(27,36,48,.4); }
.sh-book img { width: 100%; height: auto; display: block; }
.sh-no {
  position: absolute; top: 8px; left: 8px; z-index: 2;
  background: var(--ink); color: #fff; font-size: 11px;
  padding: 2px 8px; letter-spacing: .2em;
}
.sh-b1 { left: 4%; width: 30%; }
.sh-b2 { left: 37%; width: 33%; }
.sh-b3 { right: 3%; width: 27%; }
.sh-tag {
  position: absolute; top: 0; left: 2%; z-index: 5;
  background: var(--paper); border: 2px solid var(--ink); border-left: 5px solid var(--orange);
  padding: 8px 13px; font-size: 12.5px; font-weight: 700; letter-spacing: .1em;
}
.sh-tag i { position: absolute; top: -20px; left: 10px; width: 2px; height: 20px; background: rgba(27,36,48,.4); transform: rotate(14deg); }
.sh-badge {
  position: absolute; top: 6px; right: 2%; z-index: 5;
  background: var(--blue); color: #fff; border: 2px solid var(--ink);
  border-radius: 10px; padding: 8px 14px; text-align: center;
}
.sh-badge b { display: block; font-size: 21px; line-height: 1.15; }
.sh-badge span { display: block; font-size: 11px; letter-spacing: .12em; margin-top: 2px; }

/* ===== 站况数字带 ===== */
.statband { background: var(--blue); }
.statband-in {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px;
  padding-top: 36px; padding-bottom: 36px; text-align: center;
}
.st-num { display: block; font-size: 36px; font-weight: 800; color: #fff; line-height: 1.15; font-variant-numeric: tabular-nums; letter-spacing: .02em; }
.st-label { display: block; margin-top: 6px; font-size: 12.5px; color: rgba(255,255,255,.78); letter-spacing: .12em; }

/* ===== 通用区块 ===== */
.sec { padding: 76px 0; }
.sec-mist { background: var(--mist); }
.sec-h { max-width: 720px; margin: 0 0 44px; }
.sec h2 { font-size: 30px; margin: 16px 0 0; letter-spacing: .05em; line-height: 1.35; }
.sec-sub { margin: 12px 0 0; color: var(--gray); font-size: 14.5px; }

/* ===== 本领时间线 ===== */
.tl { position: relative; }
.tl::before { content: ''; position: absolute; left: 50%; top: 8px; bottom: 8px; width: 0; border-left: 2px dashed rgba(27,36,48,.28); }
.tl-it { position: relative; width: 50%; padding: 0 44px 26px 0; }
.tl-it:nth-child(even) { margin-left: 50%; padding: 0 0 26px 44px; }
.tl-it:last-child { padding-bottom: 4px; }
.tl-it::after {
  content: ''; position: absolute; top: 24px; width: 14px; height: 14px; border-radius: 50%;
  background: var(--orange); border: 3px solid #fff; outline: 2px solid rgba(27,36,48,.4);
}
.tl-it:nth-child(odd)::after { right: -10px; }
.tl-it:nth-child(even)::after { left: -10px; }
.tl-card { background: var(--paper); border: 2px solid var(--ink); padding: 20px 22px 18px; }
.tl-it:nth-child(odd) .tl-card { border-left: 6px solid var(--blue); }
.tl-it:nth-child(even) .tl-card { border-left: 6px solid var(--orange); }
.tl-no { display: inline-block; font-size: 12px; font-weight: 800; letter-spacing: .14em; color: #fff; background: var(--ink); padding: 3px 9px; }
.tl-card h3 { margin: 12px 0 0; font-size: 19px; letter-spacing: .04em; }
.tl-card p { margin: 9px 0 0; font-size: 14px; line-height: 1.85; color: var(--text); }

/* ===== 净化对照 ===== */
.vs { display: flex; align-items: stretch; gap: 22px; }
.vs-col { flex: 1 1 0; background: var(--paper); border: 2px solid var(--ink); padding: 24px 24px 22px; position: relative; }
.vs-bad { border-left: 6px solid var(--gray); }
.vs-good { border-left: 6px solid var(--blue); box-shadow: 12px 14px 0 rgba(201,106,40,.15); }
.vs-mark { position: absolute; top: -14px; left: 18px; font-size: 12px; font-weight: 800; letter-spacing: .18em; color: #fff; padding: 4px 12px; }
.vs-bad .vs-mark { background: var(--gray); }
.vs-good .vs-mark { background: var(--orange); }
.vs-col b { display: block; margin-top: 6px; font-size: 16.5px; letter-spacing: .04em; }
.vs-col p { margin: 12px 0 0; font-size: 14px; line-height: 1.95; color: var(--text); }
.vs-bad em { display: block; font-style: normal; font-size: 12.5px; color: var(--gray-l); background: var(--mist); border: 1px dashed var(--gray-l); padding: 3px 8px; margin: 8px 0; }
.vs-arrow {
  flex: 0 0 52px; align-self: center; width: 52px; height: 52px; border-radius: 50%;
  background: var(--orange); color: #fff; font-size: 24px; font-weight: 700;
  display: flex; align-items: center; justify-content: center;
}

/* ===== 五屏阶梯 ===== */
.steps { display: grid; grid-template-columns: repeat(6, 1fr); gap: 20px; align-items: start; }
.sp { position: relative; margin: 0; background: var(--paper); border: 2px solid var(--ink); padding: 10px 10px 12px; }
.sp img { width: auto; max-width: 308px; height: auto; display: block; margin: 0 auto; }
.sp-no { position: absolute; top: -2px; left: -2px; z-index: 2; background: var(--orange); color: #fff; font-size: 11px; letter-spacing: .14em; padding: 4px 9px; }
.sp figcaption { margin-top: 10px; font-size: 12.5px; color: #4d5666; text-align: center; letter-spacing: .06em; }
.sp-a, .sp-b { grid-column: span 3; }
.sp-c, .sp-d, .sp-e { grid-column: span 2; }
.sp-a { border-top: 6px solid var(--blue); }
.sp-b { border-top: 6px solid var(--orange); }
.sp-c { margin-top: -24px; border-top: 6px solid var(--orange); }
.sp-d { border-top: 6px solid var(--ink); }
.sp-e { margin-top: 24px; border-top: 6px solid var(--blue); }

/* ===== FAQ 手风琴 ===== */
.acc { max-width: 820px; margin: 0 auto; }
.acc-it { background: var(--paper); border: 2px solid var(--ink); }
.acc-it + .acc-it { margin-top: 14px; }
.acc-it[open] { box-shadow: 8px 9px 0 rgba(27,36,48,.12), -8px 9px 0 rgba(201,106,40,.12); }
.acc-q {
  display: flex; align-items: center; gap: 12px;
  padding: 17px 18px; cursor: pointer; list-style: none;
  font-weight: 700; font-size: 15.5px; letter-spacing: .02em;
}
.acc-q::-webkit-details-marker { display: none; }
.acc-no { flex: 0 0 auto; font-size: 12px; font-weight: 800; letter-spacing: .12em; color: #fff; background: var(--blue); padding: 3px 8px; }
.acc-ico { position: relative; width: 18px; height: 18px; margin-left: auto; flex: 0 0 auto; }
.acc-ico::before, .acc-ico::after { content: ''; position: absolute; background: var(--ink); transition: transform .2s ease, opacity .2s ease; }
.acc-ico::before { left: 0; right: 0; top: 8px; height: 2px; }
.acc-ico::after { top: 0; bottom: 0; left: 8px; width: 2px; }
.acc-it[open] .acc-ico::after { transform: rotate(90deg); opacity: 0; }
.acc-it[open] .acc-no { background: var(--orange); }
.acc-a { margin: 0; padding: 2px 20px 20px; font-size: 14.5px; line-height: 1.95; color: var(--text); }

/* ===== 书评卡 ===== */
.reviews { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.bk-card { position: relative; background: var(--paper); border: 2px solid var(--ink); padding: 22px 22px 18px; }
.bk-card:nth-child(odd) { border-top: 6px solid var(--orange); }
.bk-card:nth-child(even) { border-top: 6px solid var(--blue); }
.bk-card::before { content: '「'; position: absolute; top: 8px; right: 16px; font-size: 32px; font-weight: 700; color: var(--blue); opacity: .3; line-height: 1; }
.bk-star { color: var(--orange); font-size: 14px; letter-spacing: 3px; }
.bk-p { margin: 10px 0 0; font-size: 14px; line-height: 1.85; color: var(--text); }
.bk-meta { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; flex-wrap: wrap; margin-top: 14px; padding-top: 12px; border-top: 1px solid var(--line); }
.bk-meta b { font-size: 14px; letter-spacing: .02em; }
.bk-meta time { font-size: 12px; color: var(--gray-l); letter-spacing: .03em; }

/* ===== 骑缝浮卡下载 ===== */
.dl-float { position: relative; z-index: 5; margin-bottom: -78px; }
.dl-card {
  display: flex; align-items: center; justify-content: space-between; gap: 20px;
  background: var(--paper); border: 2px solid var(--ink); border-left: 10px solid var(--blue);
  padding: 26px 30px; box-shadow: 0 18px 34px rgba(27,36,48,.30);
}
.dl-l { display: flex; align-items: center; gap: 16px; }
.dl-l img { width: 56px; height: 56px; border-radius: 10px; border: 2px solid var(--line); }
.dl-l b { display: block; font-size: 19px; letter-spacing: .05em; }
.dl-l span { display: block; margin-top: 5px; font-size: 13px; color: var(--gray); letter-spacing: .08em; }
.dl-r { text-align: center; }
.dl-r p { margin: 11px 0 0; font-size: 12.5px; color: var(--gray); }

/* ===== 页脚 ===== */
.ft { background: #eef0f4; padding-top: 122px; color: var(--ink); }
.ft-in { display: flex; align-items: center; justify-content: space-between; gap: 20px; flex-wrap: wrap; padding-bottom: 26px; }
.ft .brand-t small { color: var(--gray); }
.ft-links { display: flex; gap: 22px; list-style: none; margin: 0; padding: 0; }
.ft-links a { color: var(--gray); font-size: 13.5px; text-decoration: none; }
.ft-links a:hover { color: var(--ink); }
.ft-icp { border-top: 1px solid #d8dce4; padding-top: 16px; padding-bottom: 14px; }
.ft-icp a { color: var(--gray); font-size: 12.5px; text-decoration: none; }
.ft-icp a:hover { color: var(--ink); }
.ft-c { padding-bottom: 28px; font-size: 12.5px; color: var(--gray-l); }

/* ===== 返回顶部 ===== */
.backtop {
  position: fixed; right: 24px; bottom: 160px; z-index: 60;
  width: 46px; height: 46px; border-radius: 10px; border: 0;
  background: var(--orange); color: #fff; font-size: 20px; cursor: pointer;
  opacity: 0; visibility: hidden; transform: translateY(8px);
  transition: opacity .25s ease, visibility .25s ease, transform .25s ease;
  box-shadow: 0 9px 20px rgba(201,106,40,.30);
}
.backtop.on { opacity: 1; visibility: visible; transform: none; }

/* ===== 中屏 ===== */
@media (max-width: 1080px) {
  .hero-in { gap: 32px; }
  .hero-r { flex: 0 0 400px; }
  .shelf { width: 400px; height: 520px; transform: scale(.93); transform-origin: top left; }
  .hero h1 { font-size: 38px; }
  .st-num { font-size: 30px; }
  .sp-c { margin-top: -14px; }
  .sp-e { margin-top: 14px; }
  .vs { flex-direction: column; }
  .vs-arrow { align-self: center; }
}

/* ===== 移动端 ===== */
@media (max-width: 768px) {
  .wrap { padding: 0 16px; }
  [id] { scroll-margin-top: 72px; }

  .hd-in { height: 60px; gap: 14px; }
  .nav {
    position: absolute; top: 100%; left: 0; right: 0;
    background: var(--paper); flex-direction: column; gap: 0;
    display: none; margin: 0; padding: 6px 0;
    border-bottom: 2px solid var(--ink);
    box-shadow: 0 16px 26px rgba(27,36,48,.12);
  }
  .nav.open { display: flex; }
  .nav a { padding: 13px 20px; border-bottom: 1px solid #eff1f5; border-left: 4px solid transparent; }
  .nav a.on, .nav a:hover { border-bottom-color: #eff1f5; border-left-color: var(--blue); color: var(--blue-dark); }
  .burger { display: block; }
  .hd-cta { padding: 8px 14px; font-size: 13px; }

  .hero { padding: 36px 0 48px; }
  .hero-in { flex-direction: column; align-items: stretch; gap: 36px; }
  .hero-l { flex: none; }
  .hero h1 { font-size: 32px; }
  .lead { font-size: 14.5px; }
  .hero-acts .btn-lg { padding: 13px 26px; font-size: 15px; }
  .hero-r { flex: none; }

  .shelf {
    width: 100%; max-width: 420px; height: auto; margin: 0 auto;
    display: flex; flex-wrap: wrap; gap: 14px; justify-content: center;
    padding: 4px 6px 0; transform: none; box-shadow: 22px 26px 0 rgba(90,127,178,.16);
  }
  .sh-end { display: none; }
  .sh-tag { position: static; }
  .sh-tag i { display: none; }
  .sh-badge { position: static; }
  .sh-book { position: static; bottom: auto; }
  .sh-b1 { width: calc(50% - 7px); max-width: 180px; }
  .sh-b2 { width: 100%; max-width: 300px; order: -1; }
  .sh-b3 { width: calc(50% - 7px); max-width: 180px; }
  .sh-plank { position: static; width: 100%; height: 14px; }

  .statband-in { grid-template-columns: repeat(2, 1fr); gap: 22px 14px; padding-top: 28px; padding-bottom: 28px; }
  .st-num { font-size: 28px; }

  .sec { padding: 56px 0; }
  .sec h2 { font-size: 24px; }

  .tl::before { left: 14px; }
  .tl-it, .tl-it:nth-child(even) { width: 100%; margin-left: 0; padding: 0 0 22px 44px; }
  .tl-it:nth-child(odd)::after, .tl-it:nth-child(even)::after { left: 4px; right: auto; }

  .vs-col { padding: 22px 18px 20px; }
  .vs-arrow { width: 46px; height: 46px; font-size: 20px; }

  .steps { grid-template-columns: 1fr 1fr; gap: 14px; }
  .sp-a, .sp-b, .sp-c, .sp-d, .sp-e { grid-column: span 1; margin-top: 0; }
  .sp-e { grid-column: 1 / -1; max-width: 62%; margin: 0 auto; }

  .acc-q { padding: 14px 14px; font-size: 14px; gap: 9px; }
  .acc-a { padding: 0 16px 18px; font-size: 14px; }
  .acc-it[open] { box-shadow: 8px 9px 0 rgba(27,36,48,.12), -8px 9px 0 rgba(201,106,40,.12); }

  .reviews { grid-template-columns: 1fr; gap: 16px; }
  .bk-card { padding: 18px 16px 16px; }
  .bk-p { font-size: 13.5px; }

  .dl-float { margin-bottom: -78px; }
  .dl-card { flex-direction: column; text-align: center; padding: 24px 20px; border-left-width: 2px; border-top: 6px solid var(--blue); }
  .dl-l { flex-direction: column; gap: 10px; }
  .dl-l b { font-size: 17px; }
  .ft { padding-top: 122px; }

  .backtop { right: 16px; bottom: 150px; width: 42px; height: 42px; }
}

@media (max-width: 480px) {
  .hero-points li { padding: 0 10px; font-size: 12.5px; }
  .sh-badge { padding: 6px 11px; }
  .sh-badge b { font-size: 18px; }
}

/* ===== 动效偏好 ===== */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .rv { opacity: 1; transform: none; transition: none; }
  .btn, .backtop, .acc-ico::before, .acc-ico::after { transition: none; }
}