/* =========================================================
   云开平台 · 共享样式表 /assets/site.css
   设计母题：云层透光 · 云端观测 · 数据锚点
   ========================================================= */

:root{
  /* 色彩 */
  --ink-deep:#0B1D3A;
  --ink-mid:#132A4A;
  --ink-abyss:#07111F;
  --cyan:#2FD6E8;
  --mint:#5CFFC4;
  --gold:#F2B84B;
  --cloud:#F3F7FB;
  --steel:#8FA6C4;
  --cloud-thin:#D9F6FB;
  --amber-deep:#C77E1B;

  /* 字体 */
  --font-display:"Archivo Narrow","Oswald","Noto Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-editorial:"Noto Serif SC","Source Serif 4","Songti SC",Georgia,serif;
  --font-mono:"IBM Plex Mono","JetBrains Mono","Roboto Mono","SFMono-Regular",Consolas,monospace;
  --font-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,sans-serif;

  /* 尺度 */
  --gutter:clamp(1.1rem,4vw,3rem);
  --shell:min(1240px,calc(100% - 2 * var(--gutter)));
  --radius:2px;
  --gap:clamp(1rem,2.2vw,1.75rem);
  --band-pad:clamp(2.5rem,6vw,5rem);
  --line:rgba(47,214,232,.25);
  --line-soft:rgba(143,166,196,.22);
}

/* ---------- reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{
  -webkit-text-size-adjust:100%;
  scroll-behavior:smooth;
}
body{
  margin:0;
  background:var(--ink-deep);
  color:var(--cloud);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.7;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
  overflow-x:hidden;
}
h1,h2,h3,h4,h5,h6,p,figure,blockquote{margin:0}
ul,ol{margin:0;padding:0;list-style:none}
img,svg,video{max-width:100%}
a{color:inherit}
button{font:inherit;color:inherit}
table{border-collapse:collapse;width:100%}

/* 中文排版基调 */
h1,h2,h3{font-family:var(--font-display);font-weight:800;line-height:1.15;letter-spacing:.02em}
p{letter-spacing:.01em}
:lang(zh) em,:lang(zh) i{font-style:normal}

/* ---------- 焦点与可访问性 ---------- */
:focus-visible{
  outline:2px solid var(--mint);
  outline-offset:3px;
  border-radius:var(--radius);
}
.visually-hidden{
  position:absolute!important;
  width:1px;height:1px;
  padding:0;margin:-1px;
  overflow:hidden;clip:rect(0 0 0 0);
  white-space:nowrap;border:0;
}
.skip-link{
  position:absolute;
  left:clamp(1rem,4vw,2rem);
  top:-5rem;
  z-index:200;
  padding:.7rem 1.2rem;
  background:var(--cyan);
  color:var(--ink-abyss);
  font-weight:700;
  font-size:.86rem;
  letter-spacing:.1em;
  text-decoration:none;
  border-radius:var(--radius);
  box-shadow:0 10px 30px rgba(7,17,31,.55);
  transition:top .25s ease;
}
.skip-link:focus{top:1rem}

/* =========================================================
   刊头 / 居中报头导航
   ========================================================= */
.site-header{
  position:sticky;
  top:0;
  z-index:60;
  background:linear-gradient(180deg,#07111F 0%,#0B1D3A 100%);
  border-bottom:1px solid var(--line);
  color:var(--cloud);
  isolation:isolate;
}
.site-header::before{
  content:"";
  position:absolute;
  inset:0;
  z-index:-1;
  pointer-events:none;
  background:
    radial-gradient(120% 200% at 10% -60%,rgba(47,214,232,.22),transparent 58%),
    radial-gradient(90% 180% at 88% -50%,rgba(92,255,196,.13),transparent 60%),
    radial-gradient(60% 140% at 52% -80%,rgba(242,184,75,.08),transparent 62%);
}
.header-shell{
  width:var(--shell);
  margin-inline:auto;
  display:grid;
  grid-template-columns:minmax(0,1fr) auto minmax(0,1fr);
  align-items:center;
  gap:clamp(.85rem,2.6vw,2.5rem);
  padding-block:clamp(.85rem,2vw,1.35rem);
  transition:padding-block .34s ease;
}

/* 品牌 */
.brand{
  justify-self:start;
  display:flex;
  align-items:baseline;
  gap:.75rem;
  min-width:0;
}
.brand-word{
  position:relative;
  font-family:var(--font-display);
  font-size:clamp(1.28rem,2.4vw,1.72rem);
  font-weight:800;
  letter-spacing:.16em;
  color:var(--cloud);
  text-decoration:none;
  white-space:nowrap;
  transition:font-size .34s ease,color .25s ease;
}
.brand-word::before{
  content:"";
  display:inline-block;
  width:.5rem;height:.5rem;
  margin-right:.6rem;
  background:var(--mint);
  box-shadow:0 0 0 3px rgba(92,255,196,.18);
  transform:translateY(-.12rem);
}
.brand-word:hover{color:var(--cloud-thin)}
.brand-tag{
  font-family:var(--font-editorial);
  font-size:.78rem;
  letter-spacing:.3em;
  color:var(--steel);
  white-space:nowrap;
  transition:opacity .3s ease,transform .3s ease;
}

/* 导航 */
.masthead-nav{justify-self:center}
.nav-list{
  display:flex;
  align-items:center;
  gap:clamp(.35rem,1.5vw,1.35rem);
}
.nav-link{
  position:relative;
  display:inline-block;
  padding:.55rem .25rem;
  font-size:.94rem;
  letter-spacing:.08em;
  color:var(--steel);
  text-decoration:none;
  white-space:nowrap;
  transition:color .24s ease;
}
.nav-link::after{
  content:"";
  position:absolute;
  left:0;right:0;bottom:.14rem;
  height:2px;
  background:var(--cyan);
  transform:scaleX(0);
  transform-origin:left center;
  transition:transform .3s cubic-bezier(.22,.8,.24,1);
}
.nav-link:hover{color:var(--cloud)}
.nav-link:hover::after{transform:scaleX(1)}
.nav-link[aria-current="page"]{color:var(--cloud)}
.nav-link[aria-current="page"]::after{
  transform:scaleX(1);
  background:var(--mint);
}

/* 工具区 */
.header-tools{
  justify-self:end;
  display:flex;
  align-items:center;
  gap:.55rem;
  min-width:0;
}
.version-chip{
  font-family:var(--font-mono);
  font-size:.72rem;
  letter-spacing:.14em;
  padding:.28rem .55rem;
  color:var(--mint);
  background:rgba(92,255,196,.08);
  border:1px solid rgba(92,255,196,.42);
  border-radius:var(--radius);
  white-space:nowrap;
}
.header-cta{white-space:nowrap}

.nav-toggle{
  display:none;
  flex-direction:column;
  align-items:center;
  justify-content:center;
  gap:5px;
  width:44px;height:44px;
  padding:0;
  background:rgba(19,42,74,.75);
  border:1px solid rgba(47,214,232,.4);
  border-radius:var(--radius);
  cursor:pointer;
  transition:border-color .25s ease,background .25s ease;
}
.nav-toggle:hover{border-color:var(--mint);background:rgba(47,214,232,.12)}
.nav-toggle-bar{
  display:block;
  width:20px;height:2px;
  background:var(--cloud);
  transition:transform .3s ease,opacity .2s ease;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1){transform:translateY(7px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2){opacity:0}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

/* 阅读进度轨 */
.scroll-rail{
  position:absolute;
  left:0;right:0;bottom:-1px;
  height:2px;
  background:rgba(143,166,196,.14);
  pointer-events:none;
}
.scroll-rail-fill{
  display:block;
  height:100%;
  width:100%;
  transform:scaleX(0);
  transform-origin:left center;
  background:linear-gradient(90deg,var(--cyan) 0%,var(--mint) 70%,var(--gold) 100%);
}

/* 收缩态 */
.site-header[data-compact] .header-shell{padding-block:.5rem}
.site-header[data-compact] .brand-word{font-size:1.34rem}
.site-header[data-compact] .brand-tag{
  opacity:0;
  transform:translateY(-6px);
  pointer-events:none;
}

/* =========================================================
   通用按钮
   ========================================================= */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:.5rem;
  padding:.75rem 1.35rem;
  font-family:var(--font-body);
  font-size:.88rem;
  font-weight:700;
  letter-spacing:.1em;
  line-height:1.2;
  text-decoration:none;
  border:1px solid transparent;
  border-radius:var(--radius);
  cursor:pointer;
  transition:background .25s ease,color .25s ease,border-color .25s ease,transform .2s ease;
}
.btn:active{transform:translateY(1px)}
.btn-primary{
  background:var(--cyan);
  border-color:var(--cyan);
  color:var(--ink-abyss);
}
.btn-primary:hover{background:var(--mint);border-color:var(--mint)}
.btn-ghost{
  background:transparent;
  border-color:rgba(47,214,232,.45);
  color:var(--cloud);
}
.btn-ghost:hover{border-color:var(--mint);color:var(--mint)}
.btn-gold{
  background:var(--gold);
  border-color:var(--gold);
  color:var(--ink-abyss);
}
.btn-gold:hover{background:var(--amber-deep);border-color:var(--amber-deep);color:var(--cloud)}
.btn-sm{padding:.48rem .85rem;font-size:.78rem;letter-spacing:.08em}

/* 浅底区域内的按钮反色 */
.band--cloud .btn-ghost,
.paper .btn-ghost{
  color:var(--ink-deep);
  border-color:rgba(11,29,58,.35);
}
.band--cloud .btn-ghost:hover,
.paper .btn-ghost:hover{
  color:var(--ink-abyss);
  border-color:var(--amber-deep);
  background:rgba(242,184,75,.16);
}

/* =========================================================
   容器 / 网格 / 色带
   ========================================================= */
.shell{
  width:var(--shell);
  margin-inline:auto;
}
.band{
  position:relative;
  padding-block:var(--band-pad);
}
.band--deep{background:var(--ink-deep)}
.band--midnight{background:var(--ink-mid)}
.band--abyss{background:var(--ink-abyss)}
.band--cloud{background:var(--cloud);color:var(--ink-deep)}
.band--edge{
  border-top:1px solid var(--line);
  border-bottom:1px solid var(--line);
}
.grid-12{
  display:grid;
  grid-template-columns:repeat(12,minmax(0,1fr));
  gap:var(--gap);
}

/* =========================================================
   面包屑 / 正文 / 章节编号
   ========================================================= */
.breadcrumb{
  font-size:.78rem;
  letter-spacing:.08em;
  color:var(--steel);
  padding-block:1.1rem;
}
.breadcrumb ol{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:.5rem;
}
.breadcrumb li{display:flex;align-items:center;gap:.5rem}
.breadcrumb li + li::before{
  content:"/";
  color:rgba(143,166,196,.5);
}
.breadcrumb a{
  color:var(--steel);
  text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color .22s ease,border-color .22s ease;
}
.breadcrumb a:hover{color:var(--cyan);border-bottom-color:rgba(47,214,232,.5)}

.prose{
  max-width:68ch;
  color:#D7E2F2;
  font-size:1rem;
  line-height:1.85;
}
.prose h2,.prose h3,.prose h4{color:var(--cloud);margin:1.6em 0 .7em}
.prose p{margin:0 0 1.1em}
.prose ul,.prose ol{margin:0 0 1.1em;padding-left:1.3em}
.prose ul{list-style:square}
.prose ol{list-style:decimal}
.prose li{margin-bottom:.45em}
.prose a{color:var(--cyan);text-decoration:none;border-bottom:1px solid rgba(47,214,232,.4)}
.prose a:hover{color:var(--mint);border-bottom-color:var(--mint)}
.prose strong{color:var(--cloud)}
.band--cloud .prose,.paper .prose{color:#26374F}
.band--cloud .prose h2,.band--cloud .prose h3,.paper .prose h2,.paper .prose h3{color:var(--ink-deep)}
.band--cloud .prose a,.paper .prose a{color:#0E6C7C}

.section-index{
  display:block;
  font-family:var(--font-editorial);
  font-size:clamp(2.4rem,7vw,5rem);
  line-height:.9;
  letter-spacing:.06em;
  color:transparent;
  -webkit-text-stroke:1px rgba(47,214,232,.5);
}

/* =========================================================
   组件：纸张卡片 / 标签 / 图片容器
   ========================================================= */
.paper{
  position:relative;
  background:var(--cloud);
  color:var(--ink-deep);
  border:1px solid rgba(199,126,27,.45);
  border-radius:var(--radius);
  padding:clamp(1.25rem,3vw,2rem);
  box-shadow:8px 8px 0 rgba(7,17,31,.45);
}
.paper--stack{
  box-shadow:
    8px 8px 0 rgba(7,17,31,.45),
    15px 15px 0 rgba(47,214,232,.12);
}
.paper h2,.paper h3{color:var(--ink-deep)}
.paper a{color:#0E6C7C}

.tag{
  display:inline-flex;
  align-items:center;
  gap:.35rem;
  padding:.26rem .62rem;
  font-size:.72rem;
  font-weight:700;
  letter-spacing:.12em;
  line-height:1.5;
  border-radius:var(--radius);
  background:var(--cloud-thin);
  color:var(--ink-deep);
}
.tag--cyan{background:rgba(47,214,232,.14);color:var(--cyan);border:1px solid rgba(47,214,232,.45)}
.tag--mint{background:rgba(92,255,196,.14);color:var(--mint);border:1px solid rgba(92,255,196,.45)}
.tag--gold{background:rgba(242,184,75,.14);color:var(--gold);border:1px solid rgba(242,184,75,.45)}

.figure{
  position:relative;
  margin:0;
  overflow:hidden;
  aspect-ratio:16 / 9;
  border:1px solid rgba(47,214,232,.22);
  border-radius:var(--radius);
  background:
    linear-gradient(140deg,rgba(19,42,74,.96),rgba(7,17,31,.92)),
    radial-gradient(120% 90% at 18% 8%,rgba(47,214,232,.28),transparent 60%);
}
.figure > img,
.figure > svg,
.figure > picture,
.figure > video{
  display:block;
  width:100%;
  height:100%;
  object-fit:cover;
}
.figure::after{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background:repeating-linear-gradient(0deg,rgba(243,247,251,.05) 0 1px,transparent 1px 4px);
  mix-blend-mode:overlay;
  opacity:.65;
}
.figure--wide{aspect-ratio:21 / 9}
.figure--portrait{aspect-ratio:4 / 5}
.figure--square{aspect-ratio:1 / 1}
.figure--framed{border:1px solid rgba(199,126,27,.55)}
.figure__caption{
  position:absolute;
  left:0;right:0;bottom:0;
  padding:.7rem .9rem;
  font-size:.76rem;
  letter-spacing:.06em;
  color:var(--cloud-thin);
  background:linear-gradient(180deg,rgba(7,17,31,0),rgba(7,17,31,.86));
}

/* =========================================================
   浮现 / 章节跟随
   ========================================================= */
[data-reveal]{
  opacity:0;
  transform:translateY(20px);
  transition:opacity .6s ease,transform .6s cubic-bezier(.22,.8,.24,1);
  will-change:opacity,transform;
}
[data-reveal].is-visible{opacity:1;transform:none}

[data-section-link]{transition:color .22s ease}
[data-section-link][aria-current="true"]{color:var(--mint)}

/* =========================================================
   返回顶部
   ========================================================= */
.to-top{
  position:fixed;
  right:clamp(1rem,3vw,2rem);
  bottom:clamp(1rem,3vw,2rem);
  z-index:70;
  display:grid;
  place-items:center;
  width:48px;height:48px;
  padding:0;
  font-size:1.1rem;
  line-height:1;
  color:var(--cloud);
  background:rgba(19,42,74,.92);
  border:1px solid rgba(47,214,232,.5);
  border-radius:50%;
  cursor:pointer;
  opacity:0;
  visibility:hidden;
  transform:translateY(12px);
  transition:opacity .3s ease,transform .3s ease,visibility .3s ease,border-color .25s ease,background .25s ease;
}
.to-top[data-visible]{opacity:1;visibility:visible;transform:none}
.to-top:hover{border-color:var(--mint);background:rgba(47,214,232,.2)}

/* =========================================================
   页脚
   ========================================================= */
.site-footer{
  position:relative;
  overflow:hidden;
  background:var(--ink-abyss);
  color:var(--steel);
  border-top:1px solid var(--line);
}
.footer-sky{
  position:absolute;
  inset:0;
  pointer-events:none;
  background:
    radial-gradient(70% 130% at 6% 0%,rgba(47,214,232,.16),transparent 62%),
    radial-gradient(60% 110% at 80% 8%,rgba(242,184,75,.1),transparent 60%),
    repeating-linear-gradient(90deg,rgba(143,166,196,.05) 0 1px,transparent 1px 86px);
}
.footer-shell{
  position:relative;
  width:var(--shell);
  margin-inline:auto;
  display:grid;
  grid-template-columns:1.5fr 1fr 1fr 1.4fr;
  gap:clamp(1.5rem,4vw,3rem);
  padding-block:clamp(2.6rem,6vw,4.5rem) clamp(1.6rem,4vw,2.6rem);
}
.footer-brand{max-width:32ch}
.footer-word{
  font-family:var(--font-display);
  font-size:1.5rem;
  font-weight:800;
  letter-spacing:.16em;
  color:var(--cloud);
}
.footer-word::before{
  content:"";
  display:inline-block;
  width:.45rem;height:.45rem;
  margin-right:.55rem;
  background:var(--cyan);
  transform:translateY(-.12rem);
}
.footer-tag{
  margin-top:.55rem;
  font-family:var(--font-editorial);
  font-size:.82rem;
  letter-spacing:.3em;
  color:var(--gold);
}
.footer-note{
  margin-top:.9rem;
  font-size:.86rem;
  line-height:1.8;
  color:var(--steel);
}
.footer-title{
  margin-bottom:.95rem;
  font-family:var(--font-body);
  font-size:.76rem;
  font-weight:700;
  letter-spacing:.28em;
  color:var(--cloud-thin);
}
.footer-list{display:grid;gap:.5rem}
.footer-list a{
  display:inline-block;
  font-size:.9rem;
  color:var(--steel);
  text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color .22s ease,border-color .22s ease;
}
.footer-list a:hover{color:var(--mint);border-bottom-color:rgba(92,255,196,.5)}
.footer-line{display:grid;gap:.15rem}
.footer-key{
  font-size:.7rem;
  letter-spacing:.22em;
  color:rgba(143,166,196,.72);
}
.footer-value{
  font-family:var(--font-mono);
  font-size:.84rem;
  color:var(--cloud);
  word-break:break-all;
  line-height:1.6;
}
.footer-value--text{
  font-family:var(--font-body);
  font-size:.85rem;
  color:var(--steel);
  word-break:break-word;
}
.footer-base{
  position:relative;
  width:var(--shell);
  margin-inline:auto;
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:.6rem 1.5rem;
  padding-block:1.15rem 1.7rem;
  border-top:1px solid var(--line-soft);
  font-size:.78rem;
  color:rgba(143,166,196,.85);
}
.footer-copy{letter-spacing:.04em}
.footer-legal a{
  color:rgba(217,246,251,.86);
  text-decoration:none;
  border-bottom:1px solid rgba(47,214,232,.35);
  transition:color .22s ease,border-color .22s ease;
}
.footer-legal a:hover{color:var(--mint);border-bottom-color:var(--mint)}
.footer-icp{
  font-family:var(--font-mono);
  margin-left:.5rem;
  color:rgba(143,166,196,.9);
}

/* =========================================================
   响应式
   ========================================================= */
@media (max-width:1080px){
  .brand-tag{display:none}
  .nav-list{gap:.45rem}
  .nav-link{font-size:.88rem;letter-spacing:.05em}
}

@media (max-width:1000px){
  .footer-shell{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-brand{grid-column:1 / -1;max-width:48ch}
}

@media (max-width:940px){
  .header-shell{
    grid-template-columns:minmax(0,1fr) auto;
    gap:.75rem;
  }
  .brand-tag{display:inline}
  .masthead-nav{
    position:fixed;
    top:0;right:0;bottom:0;
    width:min(360px,88vw);
    padding:5.75rem 1.6rem 2.5rem;
    background:linear-gradient(160deg,#07111F 0%,#0B1D3A 58%,#132A4A 100%);
    border-left:1px solid rgba(47,214,232,.35);
    box-shadow:-26px 0 60px rgba(7,17,31,.62);
    transform:translateX(103%);
    transition:transform .42s cubic-bezier(.22,.8,.24,1);
    overflow-y:auto;
    z-index:80;
  }
  .masthead-nav[data-open]{transform:translateX(0)}
  .nav-list{
    flex-direction:column;
    align-items:stretch;
    gap:0;
  }
  .nav-list li{border-bottom:1px solid var(--line-soft)}
  .nav-link{
    display:block;
    padding:1rem .2rem;
    font-size:1.04rem;
    letter-spacing:.1em;
  }
  .nav-link::after{left:0;right:auto;width:48px;bottom:.4rem}
  .nav-toggle{display:inline-flex}
  .grid-12{grid-template-columns:repeat(6,minmax(0,1fr))}
}

@media (max-width:680px){
  :root{--band-pad:clamp(2rem,8vw,3rem)}
  .version-chip{display:none}
  .header-cta{display:none}
  .brand-word{font-size:1.24rem}
  .brand-tag{letter-spacing:.22em;font-size:.72rem}
}

@media (max-width:560px){
  .footer-shell{grid-template-columns:1fr}
  .footer-base{flex-direction:column;align-items:flex-start}
  .grid-12{grid-template-columns:repeat(2,minmax(0,1fr))}
  .to-top{width:44px;height:44px}
}

/* =========================================================
   降低动效偏好
   ========================================================= */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms!important;
    animation-iteration-count:1!important;
    transition-duration:.001ms!important;
  }
  [data-reveal]{opacity:1;transform:none}
  .site-header[data-compact] .brand-tag{opacity:1;transform:none}
  .scroll-rail-fill{transition:none}
}