/* ===== 亿百CN · 共享样式 /assets/site.css ===== */

*,*::before,*::after{box-sizing:border-box;}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;}
body,h1,h2,h3,h4,p,ul,ol,figure,blockquote{margin:0;}
ul,ol{padding:0;list-style:none;}
img,svg{max-width:100%;display:block;}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer;}
a{color:inherit;text-decoration:none;}

:root{
  --paper:#F4F0E6;
  --mist:#A7B5A6;
  --lake:#123C4A;
  --signal:#E76F2E;
  --ink:#1B2320;
  --moss:#657B69;
  --mist-light:#D8E3E2;
  --sand:#DCCDB6;
  --ivory:#FFFDF7;
  --line:#C9C4B8;

  --body-text:#2C352F;
  --muted-text:#3E4A43;

  --font-display:"Source Han Sans SC","Noto Sans SC","PingFang SC","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-body:"Source Han Sans SC","Noto Sans SC","PingFang SC","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-mono:"IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,"Courier New",monospace;

  --wrap:1180px;
  --gutter:clamp(18px,4vw,44px);
  --hair:1px solid var(--line);
  --hard:2px solid var(--ink);
  --shadow-soft:4px 4px 0 rgba(27,35,32,.14);
  --shadow-hard:6px 6px 0 var(--ink);
}

body{
  background-color:var(--paper);
  background-image:linear-gradient(180deg,rgba(167,181,166,.28),rgba(244,240,230,0) 340px);
  color:var(--body-text);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.75;
  font-weight:400;
  -webkit-font-smoothing:antialiased;
}

h1,h2,h3,h4{color:var(--ink);font-family:var(--font-display);font-weight:800;line-height:1.2;letter-spacing:-.01em;}
p{line-height:1.85;}
::selection{background:var(--signal);color:var(--ink);}

:focus-visible{outline:3px solid var(--signal);outline-offset:2px;}

/* ===== 布局容器 ===== */
.wrap{width:100%;max-width:var(--wrap);margin-inline:auto;padding-inline:var(--gutter);}

.section{padding-block:clamp(36px,5.5vw,72px);}
.section--mist{background:var(--mist);}
.section--ivory{background:var(--ivory);}
.section--sand{background:var(--sand);}
.section--lake{background:var(--lake);color:var(--mist-light);}
.section--lake h2,.section--lake h3,.section--lake .section-title{color:var(--ivory);}

.section-head{
  display:grid;
  grid-template-columns:minmax(0,1fr) auto;
  align-items:end;
  gap:16px;
  padding-bottom:14px;
  border-bottom:var(--hard);
  margin-bottom:clamp(20px,3vw,32px);
}
.eyebrow{
  display:block;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.24em;
  text-transform:uppercase;
  color:var(--moss);
  margin-bottom:8px;
}
.section-title{font-size:clamp(24px,3.4vw,34px);}
.section-lede{max-width:62ch;font-size:15.5px;line-height:1.85;color:var(--muted-text);}
.section--lake .section-lede,.section--lake p{color:var(--mist-light);}

.rule{border:0;border-top:var(--hard);margin-block:clamp(20px,3vw,34px);}
.rule--thin{border-top:var(--hair);}

.grid{display:grid;gap:clamp(16px,2.4vw,28px);}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr));}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr));}

/* ===== 跳转链接 ===== */
.skip-link{
  position:fixed;
  top:8px;
  left:8px;
  z-index:200;
  transform:translateY(-180%);
  background:var(--ink);
  color:var(--ivory);
  border:2px solid var(--signal);
  padding:10px 18px;
  font-weight:700;
  font-size:14px;
  transition:transform .18s ease;
}
.skip-link:focus{transform:translateY(0);}

/* ===== 头部 ===== */
.site-header{position:relative;z-index:60;}

.scroll-progress{
  position:fixed;
  inset:0 0 auto 0;
  height:3px;
  z-index:90;
  pointer-events:none;
  background:transparent;
}
.scroll-progress__bar{
  display:block;
  height:100%;
  width:100%;
  transform:scaleX(0);
  transform-origin:0 50%;
  background:linear-gradient(90deg,var(--signal),var(--lake));
}

.masthead-strip{background:var(--lake);color:var(--mist-light);border-bottom:var(--hard);}
.masthead-strip__inner{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:8px 20px;
  padding-block:9px;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.16em;
}
.masthead-strip__mark{color:var(--ivory);font-weight:600;letter-spacing:.2em;}
.masthead-strip__meta{color:rgba(216,227,226,.78);}
.masthead-strip__meta--mono{color:var(--signal);}

.masthead{background:var(--paper);border-bottom:var(--hard);}
.masthead__inner{
  display:flex;
  align-items:flex-end;
  justify-content:space-between;
  gap:24px;
  padding-block:clamp(16px,2.6vw,26px) clamp(14px,2.2vw,22px);
}
.brand{display:inline-flex;align-items:center;gap:clamp(12px,1.8vw,20px);}
.brand__glyph{
  display:grid;
  place-items:center;
  width:clamp(46px,6vw,64px);
  height:clamp(46px,6vw,64px);
  background:var(--signal);
  color:var(--ink);
  border:var(--hard);
  box-shadow:5px 5px 0 var(--ink);
  font-family:var(--font-display);
  font-weight:800;
  font-size:clamp(24px,3.2vw,34px);
  line-height:1;
}
.brand__text{display:flex;flex-direction:column;gap:6px;}
.brand__name{
  font-family:var(--font-display);
  font-weight:800;
  font-size:clamp(27px,4.2vw,42px);
  line-height:1.05;
  letter-spacing:.01em;
  color:var(--ink);
}
.brand__sub{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.2em;
  color:var(--moss);
}
.masthead__note{
  writing-mode:vertical-rl;
  align-self:stretch;
  display:flex;
  justify-content:flex-start;
  padding:4px 0 0 14px;
  border-left:2px solid var(--line);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.34em;
  color:var(--moss);
  line-height:1;
}

.nav-bar{
  position:sticky;
  top:0;
  z-index:70;
  background:rgba(244,240,230,.96);
  border-bottom:var(--hard);
  backdrop-filter:blur(8px);
}
.nav-bar__inner{
  display:grid;
  grid-template-columns:1fr auto 1fr;
  align-items:center;
  gap:12px;
}
.nav-toggle{
  display:none;
  grid-column:1;
  justify-self:start;
  align-items:center;
  gap:9px;
  padding:9px 13px;
  border:var(--hard);
  background:var(--ivory);
  box-shadow:3px 3px 0 var(--ink);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.14em;
  color:var(--ink);
}
.nav-toggle__bars{display:grid;gap:3px;width:16px;}
.nav-toggle__bars span{display:block;height:2px;background:var(--ink);}
.nav-toggle[aria-expanded="true"]{background:var(--ink);color:var(--ivory);box-shadow:3px 3px 0 var(--signal);}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span{background:var(--signal);}

.primary-nav{grid-column:2;justify-self:center;}
.primary-nav__list{display:flex;flex-wrap:wrap;justify-content:center;gap:2px;}
.primary-nav__item{display:block;}
.primary-nav__link{
  display:inline-flex;
  align-items:baseline;
  gap:7px;
  padding:13px 14px;
  border-bottom:3px solid transparent;
  font-size:15px;
  font-weight:600;
  letter-spacing:.02em;
  color:var(--ink);
  transition:background-color .18s ease,color .18s ease,border-color .18s ease;
}
.primary-nav__index{font-family:var(--font-mono);font-size:10.5px;letter-spacing:.06em;color:var(--moss);}
.primary-nav__link:hover{background:var(--mist);border-bottom-color:var(--moss);}
.primary-nav__link[aria-current="page"]{
  background:var(--ink);
  color:var(--ivory);
  border-bottom-color:var(--signal);
}
.primary-nav__link[aria-current="page"] .primary-nav__index{color:var(--signal);}

.nav-cta{
  grid-column:3;
  justify-self:end;
  display:inline-flex;
  align-items:center;
  padding:9px 16px;
  background:var(--signal);
  color:var(--ink);
  border:var(--hard);
  box-shadow:3px 3px 0 var(--ink);
  font-size:13.5px;
  font-weight:700;
  letter-spacing:.05em;
  transition:transform .16s ease,box-shadow .16s ease;
}
.nav-cta:hover{transform:translate(2px,2px);box-shadow:1px 1px 0 var(--ink);}

/* ===== 页脚 ===== */
.site-footer{
  margin-top:clamp(48px,7vw,96px);
  background:var(--lake);
  color:var(--mist-light);
}
.footer-band{background:var(--signal);color:var(--ink);border-bottom:var(--hard);}
.footer-band__inner{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:6px 20px;
  padding-block:10px;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.18em;
  text-transform:uppercase;
}
.footer-band__mark{font-weight:700;}

.footer-grid{
  display:grid;
  grid-template-columns:1.5fr .9fr 1.15fr;
  gap:clamp(24px,4vw,56px);
  padding-block:clamp(34px,5vw,58px);
}
.footer-col--brand{display:flex;flex-direction:column;align-items:flex-start;gap:16px;}
.footer-brand{
  display:inline-block;
  font-family:var(--font-display);
  font-weight:800;
  font-size:clamp(26px,3.6vw,38px);
  line-height:1.1;
  color:var(--ivory);
  padding-bottom:5px;
  border-bottom:3px solid var(--signal);
}
.footer-lede{max-width:34ch;font-size:14.5px;line-height:1.85;color:#BFCFCE;}
.footer-col__title{
  font-family:var(--font-mono);
  font-size:11.5px;
  font-weight:600;
  letter-spacing:.22em;
  text-transform:uppercase;
  color:var(--signal);
  padding-bottom:10px;
  margin-bottom:14px;
  border-bottom:1px solid rgba(216,227,226,.28);
}
.footer-list li + li{margin-top:9px;}
.footer-list a{
  font-size:14.5px;
  color:var(--mist-light);
  border-bottom:1px solid transparent;
  transition:color .18s ease,border-color .18s ease;
}
.footer-list a:hover{color:var(--ivory);border-bottom-color:var(--signal);}
.footer-list a[aria-current="page"]{color:var(--signal);}
.footer-list--meta li{
  display:grid;
  grid-template-columns:52px minmax(0,1fr);
  gap:10px;
  align-items:baseline;
  margin-top:10px;
  font-size:13.5px;
  line-height:1.7;
}
.footer-key{
  font-family:var(--font-mono);
  font-size:10.5px;
  letter-spacing:.14em;
  color:rgba(216,227,226,.62);
}
.footer-value{color:#E7EEED;overflow-wrap:anywhere;}
.footer-col .btn{margin-top:18px;}

.footer-legal{border-top:1px solid rgba(216,227,226,.24);}
.footer-legal__inner{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:10px 24px;
  padding-block:18px 26px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.05em;
  color:rgba(216,227,226,.72);
}
.footer-legal__links{display:flex;flex-wrap:wrap;gap:16px;}
.footer-legal__links a{border-bottom:1px solid transparent;transition:color .18s ease,border-color .18s ease;}
.footer-legal__links a:hover{color:var(--ivory);border-bottom-color:var(--signal);}

/* ===== 按钮 ===== */
.btn{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:11px 20px;
  background:var(--ivory);
  color:var(--ink);
  border:var(--hard);
  box-shadow:4px 4px 0 var(--ink);
  font-weight:700;
  font-size:14px;
  letter-spacing:.04em;
  transition:transform .16s ease,box-shadow .16s ease,background-color .16s ease,color .16s ease;
}
.btn:hover{transform:translate(2px,2px);box-shadow:2px 2px 0 var(--ink);}
.btn--signal{background:var(--signal);color:var(--ink);}
.btn--ghost{background:transparent;}
.btn--ghost-light{
  background:transparent;
  border-color:rgba(216,227,226,.62);
  color:var(--mist-light);
  box-shadow:4px 4px 0 rgba(231,111,46,.55);
}
.btn--ghost-light:hover{background:rgba(216,227,226,.08);box-shadow:2px 2px 0 rgba(231,111,46,.55);}

/* ===== 返回顶部 ===== */
.backtop{
  position:fixed;
  right:clamp(14px,3vw,28px);
  bottom:clamp(14px,3vw,28px);
  z-index:80;
  display:grid;
  place-items:center;
  width:46px;
  height:46px;
  background:var(--ink);
  color:var(--ivory);
  border:var(--hard);
  box-shadow:4px 4px 0 var(--signal);
  font-family:var(--font-mono);
  font-size:16px;
  line-height:1;
  opacity:0;
  visibility:hidden;
  transform:translateY(10px);
  transition:opacity .24s ease,transform .24s ease,visibility .24s,background-color .18s ease,color .18s ease;
}
.backtop.is-visible{opacity:1;visibility:visible;transform:none;}
.backtop:hover{background:var(--signal);color:var(--ink);}

/* ===== 通用组件 ===== */
.mono{font-family:var(--font-mono);font-size:.92em;letter-spacing:.02em;}

.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:4px 9px;
  border:1.5px solid var(--ink);
  background:var(--ivory);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.12em;
  color:var(--ink);
}
.tag--signal{background:var(--signal);}
.tag--lake{background:var(--lake);color:var(--ivory);border-color:var(--lake);}

.card{
  background:var(--ivory);
  border:var(--hard);
  padding:clamp(18px,2.4vw,26px);
  box-shadow:var(--shadow-soft);
}
.card--offset{box-shadow:var(--shadow-hard);}
.card__title{font-size:19px;font-weight:800;margin-bottom:8px;}
.card__text{font-size:14.5px;line-height:1.8;color:var(--muted-text);}

.index-list{display:grid;border-top:var(--hard);}
.index-list__item{
  display:grid;
  grid-template-columns:auto minmax(0,1fr) auto;
  align-items:baseline;
  gap:14px;
  padding:14px 6px;
  border-bottom:var(--hair);
  transition:background-color .18s ease;
}
.index-list__item:hover{background:var(--mist-light);}
.index-list__num{font-family:var(--font-mono);font-size:12px;color:var(--signal);}
.index-list__link{font-weight:700;font-size:16.5px;color:var(--ink);}
.index-list__meta{font-family:var(--font-mono);font-size:11.5px;color:var(--moss);}

.breadcrumbs{padding-block:14px;border-bottom:var(--hair);}
.breadcrumbs__list{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.08em;
  color:var(--moss);
}
.breadcrumbs__item{display:inline-flex;align-items:center;gap:8px;}
.breadcrumbs__item + .breadcrumbs__item::before{content:"/";color:var(--line);}
.breadcrumbs__link{transition:color .18s ease;}
.breadcrumbs__link:hover{color:var(--signal);}
.breadcrumbs__item[aria-current="page"]{color:var(--ink);font-weight:700;}

.prose{max-width:70ch;font-size:16px;line-height:1.85;color:var(--body-text);}
.prose > * + *{margin-top:1.05em;}
.prose h2{font-size:clamp(20px,2.4vw,26px);margin-top:1.7em;}
.prose h3{font-size:17.5px;margin-top:1.4em;}
.prose ul li{position:relative;padding-left:18px;}
.prose ul li + li{margin-top:.5em;}
.prose ul li::before{
  content:"";
  position:absolute;
  left:0;
  top:.72em;
  width:7px;
  height:7px;
  background:var(--signal);
}
.prose a{border-bottom:2px solid var(--signal);}
.prose a:hover{background:var(--signal);color:var(--ink);}

/* ===== 图片容器基础规则 ===== */
.figure{margin:0;}
.figure__frame{
  position:relative;
  overflow:hidden;
  background:var(--mist);
  border:var(--hard);
  box-shadow:6px 6px 0 rgba(27,35,32,.16);
  aspect-ratio:16/10;
}
.figure__frame img,
.figure__frame picture,
.figure__frame > *{width:100%;height:100%;object-fit:cover;display:block;}
.figure--tall .figure__frame{aspect-ratio:4/5;}
.figure--square .figure__frame{aspect-ratio:1/1;}
.figure__caption{
  margin-top:10px;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.06em;
  color:var(--moss);
  line-height:1.7;
}

/* ===== 滚动显现 ===== */
.js-reveal [data-reveal]{
  opacity:0;
  transform:translateY(16px);
  transition:opacity .6s ease,transform .6s ease;
}
.js-reveal [data-reveal].is-visible{opacity:1;transform:none;}

/* ===== 响应式 ===== */
@media (max-width:1024px){
  .footer-grid{grid-template-columns:1fr 1fr;}
  .footer-col--brand{grid-column:1 / -1;}
  .grid--3{grid-template-columns:repeat(2,minmax(0,1fr));}
  .primary-nav__link{padding:13px 10px;font-size:14.5px;}
  .nav-cta{padding:8px 13px;font-size:13px;}
}

@media (max-width:860px){
  .nav-toggle{display:inline-flex;}
  .nav-bar__inner{grid-template-columns:1fr auto;padding-block:9px;}
  .nav-cta{grid-column:2;justify-self:end;}
  .primary-nav{
    display:none;
    grid-column:1 / -1;
    grid-row:2;
    justify-self:stretch;
    margin-top:10px;
    border-top:var(--hard);
    background:var(--paper);
  }
  .primary-nav[data-open]{display:block;}
  .primary-nav__list{flex-direction:column;gap:0;padding-bottom:14px;}
  .primary-nav__item{border-bottom:var(--hair);}
  .primary-nav__link{
    width:100%;
    justify-content:flex-start;
    padding:15px 8px;
    border-bottom:none;
    border-left:3px solid transparent;
  }
  .primary-nav__link:hover{background:var(--mist-light);border-bottom-color:transparent;border-left-color:var(--moss);}
  .primary-nav__link[aria-current="page"]{
    background:var(--ink);
    color:var(--ivory);
    border-left-color:var(--signal);
    border-bottom-color:transparent;
  }
  .masthead__note{
    writing-mode:horizontal-tb;
    align-self:auto;
    padding:6px 0 0 12px;
    border-left:0;
    border-top:0;
    letter-spacing:.22em;
    font-size:10.5px;
  }
  .grid--2,.grid--3{grid-template-columns:minmax(0,1fr);}
  .section-head{grid-template-columns:minmax(0,1fr);align-items:start;}
}

@media (max-width:600px){
  body{font-size:15.5px;}
  .masthead-strip__inner{font-size:10.5px;letter-spacing:.12em;}
  .masthead-strip__meta--mono{display:none;}
  .masthead__inner{align-items:center;gap:14px;}
  .masthead__note{display:none;}
  .brand__sub{font-size:10px;letter-spacing:.14em;}
  .footer-grid{grid-template-columns:minmax(0,1fr);gap:30px;}
  .footer-legal__inner{font-size:11px;}
  .index-list__item{grid-template-columns:auto minmax(0,1fr);row-gap:4px;}
  .index-list__meta{grid-column:2;}
}

@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto;}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
    scroll-behavior:auto !important;
  }
  .js-reveal [data-reveal]{opacity:1;transform:none;}
  .backtop{transform:none;}
}