/* ============================================================
   PP电子端 · 共享样式表 /assets/site.css
   高原夜空蓝基底 · 电子青信号色 · 信号紫渐变 · 认证暖金
   ============================================================ */

/* ---------- 01 · 设计变量 ---------- */
:root{
  --blue-night:#0B1B3A;
  --blue-deep:#122A55;
  --cyan:#22D3EE;
  --cyan-light:#A5F3FC;
  --purple:#7C5CFF;
  --purple-deep:#4B2FA8;
  --gold:#F0B429;
  --snow:#EAF2FF;
  --mist:#8FA3C8;
  --ink:#060E1F;

  --line:rgba(143,163,200,.20);
  --line-strong:rgba(34,211,238,.42);

  --font-heading:"Noto Serif SC","Source Han Serif SC","Songti SC","SimSun",Georgia,serif;
  --font-body:"Source Han Sans SC","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-mono:"IBM Plex Mono","JetBrains Mono",Menlo,Consolas,"Courier New",monospace;

  --radius-lg:26px;
  --radius-md:20px;
  --radius-sm:14px;
  --wrap:1180px;
  --shadow-card:0 24px 60px -34px rgba(75,47,168,.95);
  --ease:cubic-bezier(.22,.7,.28,1);
}

/* ---------- 02 · 重置与基底 ---------- */
*,*::before,*::after{ box-sizing:border-box }

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

body{
  margin:0;
  min-height:100vh;
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.75;
  color:var(--snow);
  background-color:var(--blue-night);
  background-image:
    radial-gradient(820px 560px at 6% -6%, rgba(124,92,255,.32), transparent 62%),
    radial-gradient(680px 480px at 104% 3%, rgba(34,211,238,.20), transparent 58%),
    repeating-linear-gradient(0deg, rgba(143,163,200,.055) 0 1px, transparent 1px 72px),
    repeating-linear-gradient(90deg, rgba(143,163,200,.055) 0 1px, transparent 1px 72px),
    linear-gradient(180deg, rgba(6,14,31,0) 42%, rgba(6,14,31,.88) 100%);
  background-repeat:no-repeat;
}

img,svg,video{ max-width:100%; display:block }

a{ color:var(--cyan-light); text-decoration:none }
a:hover{ color:#fff }

button{ font:inherit; color:inherit; background:none; border:0; cursor:pointer }

ul,ol{ margin:0; padding:0 }

p{ margin:0 0 1.1em }

[hidden]{ display:none !important }

:focus-visible{
  outline:2px solid var(--cyan-light);
  outline-offset:3px;
  border-radius:6px;
}

::selection{ background:rgba(124,92,255,.55); color:#fff }

main{ display:block }

#main-content{ scroll-margin-top:104px }

/* ---------- 03 · 排版体系 ---------- */
h1,h2,h3,h4{
  font-family:var(--font-heading);
  font-weight:800;
  line-height:1.25;
  letter-spacing:.02em;
  color:#fff;
  margin:0 0 .6em;
}
h1{ font-size:clamp(30px,4.4vw,44px) }
h2{ font-size:clamp(23px,3vw,30px) }
h3{ font-size:clamp(18px,2vw,20px) }
h4{ font-size:17px }

.mono{ font-family:var(--font-mono); letter-spacing:.08em }
.muted{ color:var(--mist) }

.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:10px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--cyan);
}

.section-num{
  display:block;
  font-family:var(--font-mono);
  font-size:clamp(30px,5vw,46px);
  line-height:1.1;
  letter-spacing:.08em;
  color:rgba(34,211,238,.26);
  -webkit-text-stroke:1px rgba(34,211,238,.75);
}

.lead{ font-size:clamp(17px,1.6vw,19px); color:#C9D8F2 }

/* ---------- 04 · 容器与网格 ---------- */
.wrap{
  width:100%;
  max-width:var(--wrap);
  margin-inline:auto;
  padding:0 24px;
}

.section{ padding-block:64px }
.section--tight{ padding-block:40px }

@media (min-width:1024px){
  .section{ padding-block:88px }
  .section--tight{ padding-block:56px }
}

.section-head{ max-width:820px; margin-bottom:34px }

.chapter-head{
  display:flex;
  align-items:flex-end;
  gap:18px;
  flex-wrap:wrap;
  margin-bottom:22px;
  padding-bottom:14px;
  border-bottom:1px solid var(--line);
}
.chapter-head h2{ margin:0 }

.content{ max-width:760px }

.grid{ display:grid; gap:22px }
.grid--2{ grid-template-columns:repeat(auto-fit,minmax(260px,1fr)) }
.grid--3{ grid-template-columns:repeat(auto-fit,minmax(230px,1fr)) }
.grid--split{ grid-template-columns:1fr; gap:32px }

@media (min-width:1024px){
  .grid--split{ grid-template-columns:minmax(0,7fr) minmax(0,4fr) }
}

/* ---------- 05 · 页面框景与滚动进度 ---------- */
body::before,
body::after{
  content:"";
  position:fixed;
  top:0;
  bottom:0;
  width:2px;
  z-index:70;
  opacity:0;
  pointer-events:none;
  background:linear-gradient(180deg,
    rgba(34,211,238,0) 0%,
    rgba(34,211,238,.55) 16%,
    rgba(124,92,255,.50) 55%,
    rgba(240,180,41,.35) 88%,
    rgba(240,180,41,0) 100%);
  transition:opacity .3s ease;
}
body::before{ left:16px }
body::after{ right:16px }

@media (min-width:1320px){
  body::before,
  body::after{ opacity:1 }
}

.scroll-progress{
  position:absolute;
  left:0;
  bottom:-2px;
  height:2px;
  width:0;
  z-index:3;
  background:linear-gradient(90deg,var(--cyan),var(--purple) 55%,var(--gold));
}

/* ---------- 06 · 页头 ---------- */
.skip-link{
  position:fixed;
  top:12px;
  left:12px;
  z-index:200;
  padding:10px 18px;
  border-radius:999px;
  background:var(--gold);
  color:#1A1400;
  font-weight:700;
  font-size:14px;
  transform:translateY(-180%);
  transition:transform .2s var(--ease);
}
.skip-link:focus{ transform:translateY(0); color:#1A1400 }

.site-header{
  position:sticky;
  top:0;
  z-index:80;
  background:linear-gradient(180deg, rgba(6,14,31,.97) 0%, rgba(11,27,58,.92) 100%);
  border-bottom:2px solid var(--line-strong);
  box-shadow:0 22px 48px -34px rgba(75,47,168,1);
}

@supports (backdrop-filter:blur(8px)){
  .site-header{ -webkit-backdrop-filter:blur(12px); backdrop-filter:blur(12px) }
}

.site-header__edge{
  height:3px;
  background:linear-gradient(90deg,var(--cyan) 0%,var(--purple) 46%,var(--gold) 92%);
}

.header-inner{
  display:grid;
  grid-template-columns:1fr auto;
  align-items:center;
  gap:14px 26px;
  padding-top:16px;
  padding-bottom:14px;
}

.brand-cluster{
  display:flex;
  align-items:center;
  gap:16px;
  min-width:0;
}

.brand{
  display:inline-flex;
  align-items:center;
  gap:12px;
  color:#fff;
}
.brand:hover{ color:#fff }

.brand__mark{
  position:relative;
  flex:0 0 34px;
  width:34px;
  height:34px;
  display:grid;
  place-items:center;
  border:2px solid var(--cyan);
  border-radius:10px;
  background:linear-gradient(140deg, rgba(34,211,238,.22), rgba(124,92,255,.34));
}

.brand__mark-core{
  width:12px;
  height:12px;
  border-radius:3px;
  background:var(--gold);
  box-shadow:0 0 12px rgba(240,180,41,.8);
  transform:rotate(45deg);
}

.brand__text{ display:flex; flex-direction:column; line-height:1.15 }

.brand__name{
  font-family:var(--font-heading);
  font-weight:800;
  font-size:19px;
  letter-spacing:.04em;
  color:#fff;
}

.brand__latin{
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.18em;
  color:var(--mist);
}

.brand-badge{
  display:none;
  align-items:center;
  gap:8px;
  margin:0;
  padding:5px 12px;
  border:1px solid rgba(240,180,41,.5);
  border-radius:999px;
  background:rgba(240,180,41,.08);
  color:var(--gold);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.08em;
  white-space:nowrap;
}

.brand-badge__dot{
  width:6px;
  height:6px;
  border-radius:50%;
  background:var(--gold);
  box-shadow:0 0 0 3px rgba(240,180,41,.18);
}

@media (min-width:640px){
  .brand-badge{ display:inline-flex }
}

/* 移动导航按钮 */
.nav-toggle{
  display:inline-flex;
  align-items:center;
  gap:10px;
  padding:10px 16px;
  border:2px solid rgba(34,211,238,.5);
  border-radius:12px;
  background:rgba(34,211,238,.06);
  color:var(--snow);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.14em;
  transition:border-color .18s ease, background .18s ease;
}
.nav-toggle:hover{ border-color:var(--cyan); background:rgba(34,211,238,.12) }

.nav-toggle__bars{ display:inline-grid; gap:4px; width:16px }
.nav-toggle__bars span{
  display:block;
  height:2px;
  background:var(--cyan);
  border-radius:2px;
  transition:transform .2s var(--ease), width .2s var(--ease);
}
.nav-toggle__bars span:nth-child(2){ width:70% }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1){ transform:translateY(6px) rotate(45deg) }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2){ width:0 }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(3){ transform:translateY(-6px) rotate(-45deg) }

.nav-toggle__text{ font-size:12px }

/* 导航基础 */
.nav-list{ list-style:none; margin:0; padding:0 }

.nav-link{
  display:flex;
  color:var(--snow);
  text-decoration:none;
  transition:color .18s ease;
}

.nav-num{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.14em;
  color:var(--cyan);
}

.nav-utility__link{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.12em;
  color:var(--mist);
  transition:color .18s ease;
}
.nav-utility__link:hover{ color:var(--cyan-light) }

/* 移动端导航面板 */
@media (max-width:1023px){
  .site-nav{
    position:absolute;
    top:100%;
    left:0;
    right:0;
    display:none;
    flex-direction:column;
    gap:18px;
    padding:20px 24px 28px;
    background:linear-gradient(180deg, rgba(6,14,31,.99), rgba(18,42,85,.99));
    border-bottom:2px solid var(--cyan);
    box-shadow:0 34px 60px -30px #000;
    max-height:calc(100vh - 92px);
    overflow-y:auto;
  }
  .site-nav[data-open]{ display:flex }

  .nav-list{ display:grid; gap:2px }
  .nav-item + .nav-item{ border-top:1px solid var(--line) }

  .nav-link{
    flex-direction:row;
    align-items:baseline;
    gap:14px;
    padding:13px 6px;
    font-size:17px;
  }
  .nav-link:hover,
  .nav-link[aria-current="page"]{ color:var(--cyan-light) }
  .nav-link[aria-current="page"] .nav-num{ color:var(--gold) }

  .nav-utility{
    display:flex;
    flex-wrap:wrap;
    align-items:center;
    gap:12px;
    padding-top:6px;
  }
}

/* 桌面端：导航嵌入页头上沿右沿 */
@media (min-width:1024px){
  .header-inner{ grid-template-columns:auto 1fr; gap:20px 34px }
  .nav-toggle{ display:none }

  .site-nav{
    display:flex;
    align-items:center;
    justify-content:flex-end;
    gap:22px;
  }

  .nav-list{ display:flex; align-items:center }

  .nav-item{ border-left:1px solid var(--line) }
  .nav-item:first-child{ border-left:0 }

  .nav-link{
    position:relative;
    flex-direction:column;
    gap:4px;
    padding:6px 15px;
    font-size:15px;
  }
  .nav-link::before{
    content:"";
    position:absolute;
    top:0;
    left:15px;
    width:12px;
    height:2px;
    background:var(--cyan);
    opacity:.6;
    transition:width .18s ease, opacity .18s ease;
  }
  .nav-link:hover::before{ width:26px; opacity:1 }
  .nav-link:hover{ color:var(--cyan-light) }
  .nav-link:hover .nav-num{ color:var(--gold) }

  .nav-link[aria-current="page"]{ color:#fff }
  .nav-link[aria-current="page"] .nav-num{ color:var(--gold) }
  .nav-link[aria-current="page"]::before{ width:26px; opacity:1 }
  .nav-link[aria-current="page"]::after{
    content:"";
    position:absolute;
    left:15px;
    right:15px;
    bottom:-6px;
    height:2px;
    border-radius:2px;
    background:linear-gradient(90deg,var(--cyan),var(--purple));
  }

  .nav-utility{ display:flex; align-items:center; gap:14px }
  .nav-utility__cta{ padding:9px 18px; font-size:14px }
}

/* ---------- 07 · 页脚 ---------- */
.site-footer{
  position:relative;
  margin-top:88px;
  border-top:2px solid rgba(34,211,238,.30);
  background:linear-gradient(180deg, rgba(6,14,31,.35) 0%, var(--ink) 55%);
}

.site-footer::before{
  content:"";
  position:absolute;
  inset:0 0 auto 0;
  height:3px;
  background:linear-gradient(90deg,var(--gold),var(--purple) 55%,var(--cyan));
  opacity:.8;
}

.footer-frame{ padding-top:60px; padding-bottom:28px }

.footer-top{
  display:grid;
  grid-template-columns:1fr;
  gap:36px;
}

@media (min-width:900px){
  .footer-top{ grid-template-columns:minmax(240px,1fr) 2fr; gap:44px }
}

.footer-brand{ display:flex; flex-direction:column; align-items:flex-start; gap:14px }

.brand--footer .brand__name{ font-size:18px }

.footer-brand__line{
  margin:0;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.1em;
  color:var(--mist);
}

.footer-cta{ margin-top:4px }

.footer-index{
  display:grid;
  grid-template-columns:1fr;
  gap:26px;
}

@media (min-width:640px){
  .footer-index{ grid-template-columns:repeat(3,minmax(0,1fr)) }
}

.footer-col__title{
  display:flex;
  align-items:baseline;
  gap:10px;
  margin:0;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.14em;
  color:var(--cyan-light);
}

.footer-col__num{ color:var(--gold) }

.footer-links{
  list-style:none;
  margin:14px 0 0;
  padding:0;
  display:grid;
  gap:10px;
}

.footer-links a{
  color:var(--mist);
  font-size:15px;
  border-bottom:1px solid transparent;
  transition:color .18s ease, border-color .18s ease;
}
.footer-links a:hover{
  color:var(--snow);
  border-bottom-color:var(--cyan);
}

.footer-meta{
  margin-top:48px;
  padding-top:24px;
  border-top:1px solid var(--line);
  display:grid;
  grid-template-columns:1fr;
  gap:8px 28px;
}

@media (min-width:768px){
  .footer-meta{ grid-template-columns:repeat(auto-fit,minmax(260px,1fr)) }
}

.footer-meta__item{ margin:0; font-size:14px }

.footer-contact{
  color:var(--snow);
  font-family:var(--font-mono);
  font-size:13px;
  letter-spacing:.04em;
}

.footer-address{ color:var(--mist) }

.footer-note{ color:var(--mist); font-size:13px }

.footer-legal{
  margin-top:26px;
  padding-top:18px;
  border-top:1px solid var(--line);
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:12px 26px;
  justify-content:space-between;
}

.footer-legal__item{
  margin:0;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.08em;
  color:var(--mist);
}

.to-top{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:9px 16px;
  border:1px solid rgba(34,211,238,.45);
  border-radius:999px;
  background:rgba(34,211,238,.08);
  color:var(--cyan-light);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.1em;
  transition:border-color .18s ease, color .18s ease, transform .18s ease;
}
.to-top:hover{ border-color:var(--cyan); color:#fff; transform:translateY(-2px) }

/* ---------- 08 · 按钮 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:10px;
  padding:12px 24px;
  border:2px solid transparent;
  border-radius:999px;
  font-family:var(--font-body);
  font-size:15px;
  font-weight:600;
  text-decoration:none;
  cursor:pointer;
  transition:transform .18s var(--ease), background .18s ease, border-color .18s ease, color .18s ease;
}
.btn:hover{ transform:translateY(-2px) }

.btn--primary{
  background:linear-gradient(120deg,var(--cyan) 0%,var(--purple) 100%);
  color:#04121F;
}
.btn--primary:hover{ color:#04121F }

.btn--ghost{
  border-color:rgba(34,211,238,.6);
  background:rgba(34,211,238,.06);
  color:var(--snow);
}
.btn--ghost:hover{ border-color:var(--cyan); color:#fff }

.btn--gold{
  border-color:var(--gold);
  background:rgba(240,180,41,.10);
  color:var(--gold);
}
.btn--gold:hover{ background:rgba(240,180,41,.18); color:#FFD57A }

/* ---------- 09 · 卡片与标签 ---------- */
.card{
  position:relative;
  padding:26px;
  border:2px solid rgba(34,211,238,.22);
  border-radius:var(--radius-lg);
  background:linear-gradient(160deg, rgba(18,42,85,.90), rgba(11,27,58,.86));
  transition:transform .18s var(--ease), border-color .18s ease, box-shadow .18s ease;
}

.card--lift:hover{
  transform:translateY(-4px);
  border-color:rgba(34,211,238,.65);
  box-shadow:var(--shadow-card);
}

.card__num{
  display:block;
  font-family:var(--font-mono);
  font-size:13px;
  letter-spacing:.12em;
  color:var(--gold);
}

.card__title{
  font-family:var(--font-heading);
  font-size:20px;
  margin:10px 0 8px;
}

.card__text{
  margin:0;
  font-size:15px;
  color:var(--mist);
}

.chip{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:5px 12px;
  border:1px solid var(--line-strong);
  border-radius:999px;
  background:rgba(34,211,238,.08);
  color:var(--cyan-light);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.08em;
}

.chip--gold{
  border-color:rgba(240,180,41,.5);
  background:rgba(240,180,41,.08);
  color:var(--gold);
}

/* ---------- 10 · 概览统计 ---------- */
.stat{
  padding:20px 22px;
  border:1px solid var(--line);
  border-radius:var(--radius-md);
  background:rgba(18,42,85,.55);
}

.stat__num{
  display:block;
  font-family:var(--font-mono);
  font-size:clamp(26px,3.4vw,36px);
  line-height:1.1;
  letter-spacing:.04em;
  color:#fff;
}

.stat__label{
  display:block;
  margin-top:6px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.1em;
  color:var(--mist);
}

/* ---------- 11 · 编号索引列表 ---------- */
.index-list{
  list-style:none;
  margin:0;
  padding:0;
  border-top:1px solid var(--line);
}
.index-list > li{ border-bottom:1px solid var(--line) }

.index-link{
  display:flex;
  align-items:baseline;
  gap:14px;
  padding:13px 4px;
  color:var(--snow);
  transition:color .18s ease, padding-left .18s ease;
}
.index-link:hover{ color:var(--cyan-light); padding-left:10px }

.index-link .idx{
  min-width:26px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.1em;
  color:var(--cyan);
}

/* ---------- 12 · 横向卡片轨道 ---------- */
.rail{ position:relative }

.rail__track{
  display:grid;
  grid-auto-flow:column;
  grid-auto-columns:minmax(240px,300px);
  gap:18px;
  padding:6px 4px 16px;
  overflow-x:auto;
  scroll-snap-type:x mandatory;
  -webkit-overflow-scrolling:touch;
}
.rail__track > *{ scroll-snap-align:start }

.rail__track::-webkit-scrollbar{ height:6px }
.rail__track::-webkit-scrollbar-track{ background:rgba(143,163,200,.14); border-radius:99px }
.rail__track::-webkit-scrollbar-thumb{
  background:linear-gradient(90deg,var(--cyan),var(--purple));
  border-radius:99px;
}

.rail__hint{
  display:block;
  margin-top:6px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.1em;
  color:var(--mist);
}

/* ---------- 13 · 图片容器基础规则 ---------- */
.media{
  position:relative;
  overflow:hidden;
  border:2px solid rgba(34,211,238,.25);
  border-radius:var(--radius-lg);
  background:
    linear-gradient(140deg, rgba(124,92,255,.28) 0%, rgba(34,211,238,.14) 58%, rgba(6,14,31,.6) 100%);
}

.media img{
  width:100%;
  height:100%;
  object-fit:cover;
  display:block;
}

.media--wide{ aspect-ratio:16 / 9 }
.media--band{ aspect-ratio:21 / 9 }
.media--square{ aspect-ratio:1 / 1 }
.media--tall{ aspect-ratio:4 / 5 }

.media__caption{
  position:absolute;
  inset:auto 0 0 0;
  padding:14px 18px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.08em;
  color:var(--snow);
  background:linear-gradient(0deg, rgba(6,14,31,.92), transparent);
}

/* ---------- 14 · 面包屑与辅助 ---------- */
.breadcrumb{ margin:28px 0 0 }

.breadcrumb__list{
  display:flex;
  flex-wrap:wrap;
  gap:8px;
  list-style:none;
  margin:0;
  padding:0;
  font-size:13px;
  color:var(--mist);
}

.breadcrumb__list li + li::before{
  content:"/";
  margin-right:8px;
  color:rgba(143,163,200,.6);
}

.breadcrumb__list a{ color:var(--cyan-light); border-bottom:1px solid transparent }
.breadcrumb__list a:hover{ border-bottom-color:var(--cyan) }

.visually-hidden{
  position:absolute !important;
  width:1px;
  height:1px;
  margin:-1px;
  padding:0;
  overflow:hidden;
  clip:rect(0 0 0 0);
  clip-path:inset(50%);
  white-space:nowrap;
  border:0;
}

/* ---------- 15 · 滚动显现 ---------- */
.js-reveal [data-reveal]{
  opacity:0;
  transform:translateY(12px);
  transition:opacity .45s ease, transform .45s var(--ease);
  transition-delay:var(--reveal-delay,0ms);
}
.js-reveal [data-reveal].is-visible{
  opacity:1;
  transform:none;
}

/* ---------- 16 · 动效降级 ---------- */
@media (prefers-reduced-motion: reduce){
  html{ scroll-behavior:auto }

  .js-reveal [data-reveal]{
    opacity:1 !important;
    transform:none !important;
    transition:none !important;
  }

  *,*::before,*::after{
    animation-duration:.01ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.01ms !important;
  }

  .card--lift:hover,
  .btn:hover,
  .to-top:hover{ transform:none }

  body::before,
  body::after{ transition:none }
}