:root{
  --ink:#04231B;
  --ink-2:#0A3328;
  --grass:#124A39;
  --cyan:#00E6B8;
  --cyan-soft:#8CFFE4;
  --orange:#FF8A3D;
  --yellow:#FFD166;
  --paper:#F2FAF6;
  --text:#EAF7F0;
  --muted:#8FB3A7;
  --line:#2A5A4A;

  --font-display:'Barlow Condensed','Oswald','Noto Sans SC','Source Han Sans SC',sans-serif;
  --font-body:'Noto Sans SC','Source Han Sans SC','PingFang SC','Microsoft YaHei',sans-serif;
  --font-mono:'IBM Plex Mono','Roboto Mono','SFMono-Regular',monospace;

  --shell:1180px;
  --gutter:clamp(1rem,4vw,2.5rem);
  --radius:2px;
  --ease:160ms ease;
  --shadow-paper:6px 6px 0 0 var(--grass);
  --shadow-lift:0 12px 26px -16px rgba(0,0,0,.9);
}

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

body{
  min-height:100%;
  background:
    radial-gradient(120% 78% at 50% -12%, rgba(0,230,184,.10), rgba(4,35,27,0) 62%),
    var(--ink);
  color:var(--text);
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.75;
  letter-spacing:.01em;
  text-rendering:optimizeLegibility;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}

h1,h2,h3,h4{
  font-family:var(--font-display);
  font-weight:700;
  line-height:1.14;
  letter-spacing:-.01em;
  text-wrap:balance;
}
h1{font-size:clamp(2.5rem,6vw,4rem);}
h2{font-size:clamp(1.75rem,3.4vw,2.5rem);}
h3{font-size:clamp(1.25rem,2vw,1.6rem);}
p,li{text-wrap:pretty;}
strong{color:var(--cyan-soft);font-weight:700;}

:focus-visible{
  outline:2px solid var(--cyan-soft);
  outline-offset:3px;
  border-radius:var(--radius);
}
#main-content{display:block;scroll-margin-top:150px;}
#main-content:focus{outline:none;}

/* ---------- 容器与通用 ---------- */
.shell{
  width:100%;
  max-width:calc(var(--shell) + var(--gutter) * 2);
  margin-inline:auto;
  padding-inline:var(--gutter);
}
.section{padding-block:clamp(2.5rem,6vw,5rem);}
.section--paper{
  background:var(--paper);
  color:var(--ink-2);
  box-shadow:inset 0 0 0 1px rgba(10,51,40,.14);
}
.section--paper h1,.section--paper h2,.section--paper h3{color:var(--ink-2);}
.section--paper .eyebrow{color:#0B6B54;}
.section--paper .lede{color:#3C6557;}
.section--paper .tag{border-color:#0B6B54;color:#0B6B54;background:rgba(11,107,84,.08);}
.section--paper .media-caption{color:#4A7566;}

.eyebrow{
  display:inline-block;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.24em;
  text-transform:uppercase;
  color:var(--cyan);
  margin-bottom:.75rem;
}
.chapter-no{
  display:inline-flex;
  align-items:center;
  gap:.55rem;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.24em;
  color:var(--cyan);
}
.chapter-no::before{
  content:"";
  width:30px;
  height:8px;
  background:var(--cyan);
  transform:skewX(-24deg);
}
.lede{
  max-width:62ch;
  font-size:clamp(1rem,1.4vw,1.15rem);
  line-height:1.85;
  color:var(--muted);
}
.mono{font-family:var(--font-mono);letter-spacing:.08em;}

.tag{
  display:inline-flex;
  align-items:center;
  gap:.35rem;
  padding:.2rem .55rem;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.14em;
  text-transform:uppercase;
  color:var(--cyan-soft);
  background:rgba(0,230,184,.08);
  border:1px solid var(--line);
}
.tag--orange{color:#FFD3B4;background:rgba(255,138,61,.14);border-color:#8A4B22;}
.tag--yellow{color:var(--yellow);background:rgba(255,209,102,.12);border-color:#7A6230;}
.tag--paper{color:var(--ink-2);background:var(--paper);border-color:var(--ink-2);}

/* ---------- 按钮 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:.5rem;
  padding:.68rem 1.15rem;
  font-family:var(--font-display);
  font-size:1.02rem;
  font-weight:600;
  letter-spacing:.04em;
  color:var(--text);
  border:1px solid var(--line);
  background:transparent;
  cursor:pointer;
  transition:transform var(--ease),background-color var(--ease),color var(--ease),border-color var(--ease);
}
.btn--primary{
  background:var(--orange);
  border-color:var(--orange);
  color:#201005;
  box-shadow:3px 3px 0 0 rgba(0,0,0,.45);
}
.btn--primary:hover{background:#FFA367;border-color:#FFA367;transform:translateY(-2px);}
.btn--ghost{background:transparent;border-color:var(--line);color:var(--text);}
.btn--ghost:hover{border-color:var(--cyan);color:var(--cyan);transform:translateY(-2px);}

/* ---------- 跳转链接 ---------- */
.skip-link{
  position:absolute;
  left:1rem;
  top:-5rem;
  z-index:200;
  padding:.6rem 1rem;
  font-family:var(--font-mono);
  font-size:13px;
  letter-spacing:.1em;
  color:var(--ink);
  background:var(--cyan);
  transition:top var(--ease);
}
.skip-link:focus{top:.6rem;}

/* ---------- 头部 ---------- */
.site-header{
  position:sticky;
  top:0;
  z-index:80;
  background:var(--ink);
  border-bottom:1px solid var(--line);
  box-shadow:0 1px 0 0 rgba(140,255,228,.08);
}
.header-strip{
  background:var(--ink-2);
  border-bottom:1px solid var(--line);
}
.header-strip__inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:1rem;
  padding-block:.5rem;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.16em;
  color:var(--muted);
}
.header-strip__tag{color:var(--cyan);letter-spacing:.22em;}
.header-strip__line{color:var(--muted);}
.header-strip__meta{
  color:var(--muted);
  padding-left:.7rem;
  border-left:1px solid var(--line);
  white-space:nowrap;
}

.masthead{
  display:grid;
  grid-template-columns:1fr auto 1fr;
  grid-template-areas:"aside brand actions";
  align-items:center;
  gap:1rem;
  padding-block:1rem .95rem;
}
.masthead__aside{
  grid-area:aside;
  display:grid;
  gap:.15rem;
  justify-self:start;
}
.masthead__aside-kicker{
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.28em;
  text-transform:uppercase;
  color:var(--muted);
}
.masthead__aside-text{
  font-family:var(--font-mono);
  font-size:13px;
  letter-spacing:.1em;
  color:var(--cyan);
}
.masthead__brand{
  grid-area:brand;
  justify-self:center;
  display:grid;
  justify-items:center;
  gap:.3rem;
  padding-inline:.5rem;
  text-decoration:none;
}
.masthead__mark{
  position:relative;
  isolation:isolate;
  display:inline-block;
  padding:0 .18em;
  font-family:var(--font-display);
  font-size:clamp(2rem,4.6vw,3.1rem);
  font-weight:700;
  line-height:1;
  letter-spacing:-.02em;
  color:var(--text);
  transition:color var(--ease);
}
.masthead__mark::before{
  content:"";
  position:absolute;
  inset:.3em -.12em .05em -.12em;
  z-index:-1;
  background:linear-gradient(100deg,rgba(0,230,184,.24),rgba(0,230,184,0) 78%);
  transform:skewX(-8deg);
  transition:background-color var(--ease);
}
.masthead__brand:hover .masthead__mark,
.masthead__brand:focus-visible .masthead__mark{color:var(--cyan-soft);}
.masthead__sub{
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.28em;
  text-transform:uppercase;
  color:var(--muted);
}
.masthead__actions{
  grid-area:actions;
  justify-self:end;
  display:flex;
  align-items:center;
  gap:.6rem;
}
.masthead__cta{white-space:nowrap;}

.nav-toggle{
  display:none;
  align-items:center;
  gap:.5rem;
  padding:.5rem .7rem;
  border:1px solid var(--line);
  color:var(--text);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.14em;
  cursor:pointer;
  transition:border-color var(--ease),color var(--ease);
}
.nav-toggle:hover{border-color:var(--cyan);color:var(--cyan);}
.nav-toggle__bars{display:flex;flex-direction:column;gap:4px;}
.nav-toggle__bars span{
  display:block;
  width:18px;
  height:2px;
  background:var(--cyan);
  transition:transform var(--ease),opacity var(--ease);
}
.nav-toggle__label{line-height:1;}

.nav-bar{
  border-top:1px solid var(--line);
  background:var(--ink);
}
.nav-bar__inner{
  display:flex;
  align-items:center;
  justify-content:center;
  padding-block:.1rem .3rem;
}
.nav-bar__cta{display:none;}
.nav-list{
  display:flex;
  flex-wrap:wrap;
  justify-content:center;
  gap:.2rem;
}
.nav-link{
  position:relative;
  isolation:isolate;
  display:inline-block;
  padding:.55rem 1rem;
  font-family:var(--font-display);
  font-size:1.05rem;
  font-weight:600;
  letter-spacing:.04em;
  color:var(--text);
  text-decoration:none;
  transition:color var(--ease);
}
.nav-link::before{
  content:"";
  position:absolute;
  inset:.18rem .1rem;
  z-index:-1;
  background:rgba(0,230,184,.16);
  transform:skewX(-8deg) scaleX(.86);
  opacity:0;
  transition:opacity var(--ease),transform var(--ease);
}
.nav-link:hover::before,
.nav-link:focus-visible::before{opacity:1;transform:skewX(-8deg) scaleX(1);}
.nav-link:hover{color:var(--cyan-soft);}
.nav-link[aria-current="page"]{
  background:var(--cyan);
  color:var(--ink);
}
.nav-link[aria-current="page"]::before{opacity:0;}

.header-progress{
  position:absolute;
  left:0;
  bottom:-1px;
  width:0;
  height:2px;
  background:linear-gradient(90deg,var(--cyan),var(--yellow));
  pointer-events:none;
}

/* ---------- 页脚 ---------- */
.site-footer{
  position:relative;
  border-top:1px solid var(--line);
  background:linear-gradient(180deg,var(--ink) 0%,var(--ink-2) 24%,var(--ink-2) 100%);
  color:var(--text);
  padding-top:6px;
}
.site-footer::before{
  content:"";
  position:absolute;
  inset:0 0 auto 0;
  height:6px;
  background:
    repeating-linear-gradient(90deg,var(--cyan) 0 1px,rgba(0,0,0,0) 1px 26px),
    linear-gradient(90deg,rgba(0,230,184,.18),rgba(255,138,61,.16));
  opacity:.55;
  pointer-events:none;
}
.footer-top{
  display:grid;
  grid-template-columns:minmax(0,1.05fr) minmax(0,2fr);
  gap:clamp(1.75rem,4vw,3rem);
  padding-block:clamp(2.5rem,5vw,3.75rem) clamp(2rem,4vw,2.75rem);
}
.footer-brand{display:grid;gap:1rem;align-content:start;}
.footer-brand__mark{
  position:relative;
  display:inline-block;
  justify-self:start;
  padding-bottom:.25rem;
  font-family:var(--font-display);
  font-size:clamp(1.9rem,4vw,2.8rem);
  font-weight:700;
  line-height:1;
  letter-spacing:-.02em;
  color:var(--text);
  text-decoration:none;
  transition:color var(--ease);
}
.footer-brand__mark::after{
  content:"";
  position:absolute;
  left:0;
  right:-.35rem;
  bottom:0;
  height:3px;
  background:var(--cyan);
  transform:skewX(-8deg);
}
.footer-brand__mark:hover{color:var(--cyan-soft);}
.footer-brand__summary{
  max-width:34ch;
  font-size:.95rem;
  line-height:1.8;
  color:var(--muted);
}
.footer-brand__stamp{
  justify-self:start;
  padding:.35rem .6rem;
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.2em;
  color:var(--cyan-soft);
  border:1px solid var(--line);
  transform:rotate(-1.5deg);
}
.footer-grid{
  display:grid;
  grid-template-columns:repeat(3,minmax(0,1fr));
  gap:1.75rem;
}
.footer-col{min-width:0;}
.footer-col__title{
  margin-bottom:.85rem;
  padding-bottom:.55rem;
  font-family:var(--font-mono);
  font-size:12px;
  font-weight:500;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--cyan);
  border-bottom:1px solid var(--line);
}
.footer-links{display:grid;gap:.5rem;}
.footer-link{
  display:inline-block;
  font-size:.95rem;
  color:var(--text);
  border-bottom:1px solid transparent;
  transition:color var(--ease),border-color var(--ease),transform var(--ease);
}
.footer-link:hover,
.footer-link:focus-visible{
  color:var(--cyan);
  border-bottom-color:var(--cyan);
  transform:translateX(2px);
}
.footer-contact{display:grid;gap:.9rem;}
.footer-contact__row{display:grid;gap:.2rem;min-width:0;}
.footer-contact__label{
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--muted);
}
.footer-contact__value{
  font-size:.92rem;
  line-height:1.65;
  color:var(--text);
}
.copy-btn{
  display:inline-flex;
  align-items:center;
  gap:.5rem;
  max-width:100%;
  padding:.3rem .55rem;
  font-family:var(--font-mono);
  font-size:.82rem;
  letter-spacing:.02em;
  color:var(--cyan-soft);
  background:rgba(0,230,184,.05);
  border:1px dashed var(--line);
  cursor:pointer;
  transition:border-color var(--ease),background-color var(--ease),color var(--ease);
}
.copy-btn:hover,
.copy-btn:focus-visible{
  border-color:var(--cyan);
  border-style:solid;
  background:rgba(0,230,184,.12);
  color:var(--cyan);
}
.copy-btn__text{word-break:break-all;text-align:left;}
.copy-btn__hint{
  flex:none;
  padding-left:.5rem;
  font-size:10px;
  letter-spacing:.1em;
  color:var(--muted);
  border-left:1px solid var(--line);
}
.copy-btn.is-copied{border-color:var(--yellow);border-style:solid;}
.copy-btn.is-copied .copy-btn__hint{color:var(--yellow);}

.footer-legal{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:.7rem 1.4rem;
  padding-block:1.15rem 2rem;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.05em;
  color:var(--muted);
  border-top:1px solid var(--line);
}
.footer-legal__copy{margin:0;}
.footer-legal__links{display:flex;flex-wrap:wrap;gap:1.1rem;}
.footer-legal__links a{
  color:var(--muted);
  border-bottom:1px solid transparent;
  transition:color var(--ease),border-color var(--ease);
}
.footer-legal__links a:hover,
.footer-legal__links a:focus-visible{color:var(--cyan-soft);border-bottom-color:var(--cyan-soft);}

/* ---------- 通用内容组件 ---------- */
.breadcrumbs{
  padding-block:.9rem 0;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.1em;
  color:var(--muted);
}
.breadcrumbs ol{display:flex;flex-wrap:wrap;gap:.4rem;}
.breadcrumbs li{display:inline-flex;align-items:center;gap:.4rem;}
.breadcrumbs li + li::before{content:"/";color:var(--line);}
.breadcrumbs a{color:var(--muted);transition:color var(--ease);}
.breadcrumbs a:hover,.breadcrumbs a:focus-visible{color:var(--cyan);}
.breadcrumbs [aria-current="page"]{color:var(--text);}

.grid{
  display:grid;
  gap:1.25rem;
  grid-template-columns:repeat(auto-fit,minmax(240px,1fr));
}
.grid--2{grid-template-columns:repeat(auto-fit,minmax(280px,1fr));}
.grid--3{grid-template-columns:repeat(auto-fit,minmax(210px,1fr));}

.card{
  padding:1.25rem;
  background:var(--ink-2);
  border:1px solid var(--line);
  transition:transform var(--ease),border-color var(--ease),background-color var(--ease);
}
.card:hover{
  transform:translateY(-3px);
  border-color:var(--cyan);
  background:#0C3B2E;
  box-shadow:var(--shadow-lift);
}
.paper-card{
  padding:1.25rem;
  background:var(--paper);
  color:var(--ink-2);
  border:1px solid var(--ink-2);
  box-shadow:var(--shadow-paper);
  transition:transform var(--ease),box-shadow var(--ease);
}
.paper-card:hover{transform:translate(-2px,-2px);box-shadow:8px 8px 0 0 var(--grass);}
.paper-card h2,.paper-card h3{color:var(--ink-2);}

.media-frame{
  position:relative;
  overflow:hidden;
  background:var(--grass);
  border:1px solid var(--line);
}
.media-frame::after{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  box-shadow:inset 0 0 0 1px rgba(0,230,184,.2);
}
.media-frame img,
.media-frame picture > img{
  width:100%;
  height:100%;
  object-fit:cover;
  transition:transform 240ms ease;
}
.media-frame--wide{aspect-ratio:16/9;}
.media-frame--tall{aspect-ratio:4/5;}
.media-frame--square{aspect-ratio:1/1;}
.media-frame:hover img{transform:scale(1.02);}
.media-caption{
  margin-top:.6rem;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.06em;
  line-height:1.6;
  color:var(--muted);
}

.prose{
  max-width:72ch;
  font-size:1.02rem;
  line-height:1.85;
}
.prose > * + *{margin-top:1.1em;}
.prose h2,.prose h3{margin-top:1.8em;color:var(--text);}
.prose ul,.prose ol{list-style:revert;padding-left:1.35em;}
.prose li + li{margin-top:.35em;}
.prose a{color:var(--cyan);text-decoration:underline;text-underline-offset:3px;}
.prose a:hover{color:var(--cyan-soft);}
.prose strong{color:var(--cyan-soft);}

/* ---------- 响应式 ---------- */
@media (max-width:1080px){
  .masthead__aside{display:none;}
}
@media (max-width:900px){
  .footer-top{grid-template-columns:1fr;}
  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr));}
}
@media (max-width:860px){
  :root{--gutter:clamp(1rem,5vw,1.5rem);}
  .header-strip__inner{font-size:10px;letter-spacing:.12em;}
  .masthead{
    grid-template-columns:1fr auto;
    grid-template-areas:"brand actions";
    padding-block:.8rem;
  }
  .masthead__brand{justify-self:start;justify-items:start;padding-inline:0;}
  .masthead__sub{letter-spacing:.2em;}
  .masthead__cta{display:none;}
  .nav-toggle{display:inline-flex;}
  .nav-bar{display:none;background:var(--ink-2);}
  .site-header[data-open="true"] .nav-bar{display:block;}
  .nav-bar__inner{
    display:block;
    padding-block:.25rem .9rem;
    max-width:calc(var(--shell) + var(--gutter) * 2);
  }
  .nav-list{flex-direction:column;gap:0;}
  .nav-list li + li{border-top:1px solid rgba(42,90,74,.6);}
  .nav-link{display:block;padding:.8rem .2rem;font-size:1.15rem;}
  .nav-link::before{display:none;}
  .nav-link[aria-current="page"]{
    background:transparent;
    color:var(--cyan);
    box-shadow:inset 3px 0 0 var(--cyan);
    padding-left:.85rem;
  }
  .nav-bar__cta{display:inline-flex;width:100%;margin-top:1rem;}
  .site-header[data-open="true"] .nav-toggle__bars span:nth-child(1){transform:translateY(6px) rotate(45deg);}
  .site-header[data-open="true"] .nav-toggle__bars span:nth-child(2){opacity:0;}
  .site-header[data-open="true"] .nav-toggle__bars span:nth-child(3){transform:translateY(-6px) rotate(-45deg);}
  #main-content{scroll-margin-top:120px;}
}
@media (max-width:620px){
  body{font-size:16px;}
  .header-strip__line{display:none;}
  .footer-grid{grid-template-columns:1fr;}
  .footer-legal{flex-direction:column;align-items:flex-start;font-size:11px;}
  .media-frame--wide{aspect-ratio:4/3;}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto;}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  .btn--primary:hover,
  .btn--ghost:hover,
  .card:hover,
  .paper-card:hover,
  .footer-link:hover{transform:none;}
  .media-frame:hover img{transform:none;}
}