:root{
  --ink:#161A1F;
  --fog:#3A3F47;
  --paper:#F3EEE5;
  --paper-2:#E4DCCF;
  --red:#D6402F;
  --red-deep:#A92A1E;
  --cyan:#2EC4B6;
  --cyan-deep:#167F78;
  --amber:#C9821B;
  --line:#C9C2B6;
  --white:#FBF8F1;

  --maxw:1240px;
  --gut:24px;
  --rail:72px;
  --dur:160ms;
  --ease:cubic-bezier(.2,.7,.3,1);
  --shadow-hard:4px 4px 0 rgba(58,63,71,.14);
  --shadow-hard-lift:6px 6px 0 rgba(58,63,71,.18);

  --font-head:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-body:"Noto Serif SC","Source Han Serif SC","Songti SC","SimSun",Georgia,"Times New Roman",serif;
  --font-mono:"JetBrains Mono",ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,monospace;
}

*,*::before,*::after{box-sizing:border-box}

html{
  -webkit-text-size-adjust:100%;
  scroll-behavior:smooth;
  scroll-padding-top:96px;
}

body{
  margin:0;
  background:var(--paper);
  color:var(--fog);
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.78;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
}

p{margin:0 0 1em}

h1,h2,h3,h4,h5,h6{
  margin:0 0 .5em;
  font-family:var(--font-head);
  font-weight:900;
  letter-spacing:.02em;
  line-height:1.1;
  color:var(--ink);
}
h1{font-size:clamp(32px,4.6vw,58px);line-height:1.06}
h2{font-size:clamp(24px,3vw,36px);line-height:1.12}
h3{font-size:clamp(19px,2.2vw,25px);line-height:1.26}

a{color:var(--red-deep);text-decoration:underline;text-underline-offset:3px}
a:hover{color:var(--red)}

img,svg,video{display:block;max-width:100%}
button{font:inherit;color:inherit}
table{border-collapse:collapse;width:100%}

:focus-visible{outline:2px solid var(--red);outline-offset:3px}
.site-header :focus-visible,
.site-footer :focus-visible{outline-color:var(--cyan)}

/* ---------- 容器 ---------- */
.shell{
  width:100%;
  max-width:var(--maxw);
  margin-left:auto;
  margin-right:auto;
  padding-left:var(--gut);
  padding-right:var(--gut);
}

.section{padding:clamp(40px,6vw,72px) 0}
.section--tight{padding:clamp(24px,3.4vw,36px) 0}

.section-head{
  display:flex;
  flex-wrap:wrap;
  align-items:flex-end;
  justify-content:space-between;
  gap:12px 24px;
  padding-bottom:12px;
  margin-bottom:clamp(20px,3vw,32px);
  border-bottom:1px solid var(--line);
}
.section-head__title{
  margin:0;
  font-family:var(--font-head);
  font-weight:900;
  font-size:clamp(21px,2.6vw,30px);
  line-height:1.16;
  letter-spacing:.02em;
  color:var(--ink);
}
.section-head__meta{
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.06em;
  color:var(--fog);
  font-variant-numeric:tabular-nums;
}

.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:10px;
  margin-bottom:14px;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.16em;
  color:var(--red-deep);
}
.eyebrow::before{content:"";width:22px;height:1px;background:var(--red)}

.prose{max-width:34em}
.prose p:last-child{margin-bottom:0}
.prose a{color:var(--red-deep)}

.mono{
  font-family:var(--font-mono);
  font-variant-numeric:tabular-nums;
  letter-spacing:.02em;
}

.divider{height:1px;border:0;background:var(--line);margin:0}

/* ---------- 按钮 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  gap:10px;
  padding:12px 20px;
  border:1px solid transparent;
  font-family:var(--font-head);
  font-weight:700;
  font-size:14.5px;
  letter-spacing:.02em;
  line-height:1.2;
  text-decoration:none;
  cursor:pointer;
  transition:transform var(--dur) var(--ease),background-color var(--dur) var(--ease),color var(--dur) var(--ease),border-color var(--dur) var(--ease),box-shadow var(--dur) var(--ease);
}
.btn--primary{
  background:var(--red);
  border-color:var(--red);
  color:var(--white);
  box-shadow:var(--shadow-hard);
}
.btn--primary:hover{
  background:var(--red-deep);
  border-color:var(--red-deep);
  color:var(--white);
  transform:translate(-2px,-2px);
  box-shadow:var(--shadow-hard-lift);
}
.btn--ghost{
  background:transparent;
  border-color:var(--ink);
  color:var(--ink);
}
.btn--ghost:hover{background:var(--ink);color:var(--paper)}
.btn--quiet{
  padding:6px 0;
  background:transparent;
  border-color:transparent;
  color:var(--red-deep);
  border-bottom:1px solid var(--line);
}
.btn--quiet:hover{color:var(--red);border-bottom-color:var(--red)}
.btn__arrow{font-family:var(--font-mono);font-size:13px;line-height:1}
.btn[data-copied]{background:var(--cyan-deep);border-color:var(--cyan-deep);color:var(--white)}

/* ---------- 标签 ---------- */
.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:3px 8px;
  border:1px solid currentColor;
  font-family:var(--font-mono);
  font-size:11px;
  line-height:1.5;
  letter-spacing:.06em;
  white-space:nowrap;
}
.tag--fix{color:var(--cyan-deep);background:rgba(46,196,182,.12)}
.tag--update{color:var(--cyan-deep);background:rgba(46,196,182,.08)}
.tag--warn{color:var(--amber);background:rgba(201,130,27,.12)}
.tag--live{color:var(--red-deep);background:rgba(214,64,47,.1)}
.tag--muted{color:var(--fog);border-color:var(--line);background:transparent}
.tag__dot{width:6px;height:6px;border-radius:50%;background:currentColor}

/* ---------- 面包屑 ---------- */
.breadcrumb{margin:0 0 20px}
.breadcrumb__list{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  margin:0;
  padding:0;
  list-style:none;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.06em;
  color:var(--fog);
}
.breadcrumb__item{display:inline-flex;align-items:center;gap:8px}
.breadcrumb__link{
  color:var(--fog);
  text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.breadcrumb__link:hover{color:var(--red-deep);border-bottom-color:var(--red-deep)}
.breadcrumb__sep{color:var(--line)}
.breadcrumb__current{color:var(--ink)}

/* ---------- 网格 ---------- */
.grid{display:grid;gap:clamp(16px,2.4vw,24px)}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid--4{grid-template-columns:repeat(4,minmax(0,1fr))}
.grid--split{grid-template-columns:minmax(0,5fr) minmax(0,7fr)}

/* ---------- 纸片卡片 ---------- */
.paper-card{
  position:relative;
  padding:20px 22px;
  background:var(--white);
  border:1px solid var(--line);
  box-shadow:var(--shadow-hard);
  transition:transform var(--dur) var(--ease),box-shadow var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.paper-card:hover{
  transform:translate(-2px,-2px);
  box-shadow:var(--shadow-hard-lift);
  border-color:var(--fog);
}
.paper-card--accent{border-top:3px solid var(--red)}
.paper-card__index{
  display:block;
  margin-bottom:8px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.12em;
  color:var(--red);
  font-variant-numeric:tabular-nums;
}
.paper-card__title{
  margin:0 0 8px;
  font-family:var(--font-head);
  font-weight:900;
  font-size:clamp(18px,2vw,22px);
  line-height:1.3;
  letter-spacing:.02em;
  color:var(--ink);
}
.paper-card__body{
  margin:0;
  font-size:15px;
  line-height:1.75;
  color:var(--fog);
}

/* ---------- 状态数字 ---------- */
.stat-group{display:flex;flex-wrap:wrap;gap:clamp(24px,4vw,48px)}
.stat{display:flex;flex-direction:column;gap:4px}
.stat__value{
  font-family:var(--font-mono);
  font-weight:500;
  font-size:clamp(30px,4.4vw,46px);
  line-height:1;
  letter-spacing:-.02em;
  color:var(--ink);
  font-variant-numeric:tabular-nums;
}
.stat__label{
  font-family:var(--font-head);
  font-size:12px;
  font-weight:500;
  letter-spacing:.08em;
  color:var(--fog);
}

/* ---------- 图片容器 ---------- */
.media-frame{
  position:relative;
  display:block;
  margin:0;
  overflow:hidden;
  background:var(--paper-2);
  border:1px solid var(--line);
  box-shadow:var(--shadow-hard);
}
.media-frame__img{
  display:block;
  width:100%;
  height:100%;
  object-fit:cover;
  filter:saturate(.62) contrast(1.04);
}
.media-frame::after{
  content:"";
  position:absolute;
  inset:auto 10px 10px auto;
  width:26px;
  height:26px;
  border-right:1px solid rgba(251,248,241,.75);
  border-bottom:1px solid rgba(251,248,241,.75);
  pointer-events:none;
}
.media-frame__caption{
  position:absolute;
  left:0;
  bottom:0;
  right:0;
  padding:22px 14px 10px;
  background:linear-gradient(to top,rgba(22,26,31,.78),rgba(22,26,31,0));
  color:var(--white);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.06em;
  line-height:1.6;
}
.media-frame--wide{aspect-ratio:16/9}
.media-frame--square{aspect-ratio:1/1}
.media-frame--tall{aspect-ratio:3/4}

/* ---------- 提示条 ---------- */
.notice{
  display:flex;
  flex-wrap:wrap;
  align-items:baseline;
  gap:6px 12px;
  padding:14px 16px;
  background:var(--paper-2);
  border:1px solid var(--line);
  border-left:3px solid var(--amber);
  font-size:15px;
  line-height:1.7;
}
.notice__title{
  font-family:var(--font-head);
  font-weight:700;
  font-size:13px;
  letter-spacing:.06em;
  color:var(--amber);
}

/* ---------- 章节轨 ---------- */
.rail{
  position:sticky;
  top:96px;
  display:flex;
  flex-direction:column;
  gap:2px;
  padding-left:14px;
  border-left:1px solid var(--line);
}
.rail__link{
  display:block;
  padding:5px 0;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.04em;
  color:var(--fog);
  text-decoration:none;
  transition:color var(--dur) var(--ease);
}
.rail__link:hover{color:var(--red-deep)}
.rail__link[aria-current]{
  color:var(--red-deep);
  font-weight:500;
}

/* ==========================================================================
   头部命令栏
   ========================================================================== */
.site-header{
  position:sticky;
  top:0;
  z-index:100;
  background:var(--ink);
  color:var(--paper);
  border-bottom:1px solid rgba(201,194,182,.28);
}

.skip-link{
  position:absolute;
  left:12px;
  top:-80px;
  z-index:200;
  padding:10px 16px;
  background:var(--red);
  color:var(--white);
  font-family:var(--font-head);
  font-weight:700;
  font-size:13px;
  letter-spacing:.02em;
  text-decoration:none;
  transition:top var(--dur) var(--ease);
}
.skip-link:focus{top:12px;color:var(--white)}

.cmdbar__inner{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:10px 18px;
  max-width:var(--maxw);
  margin:0 auto;
  padding:9px var(--gut);
  min-height:64px;
}

.cmdbar__brand{
  display:flex;
  align-items:center;
  gap:12px;
  min-width:0;
  order:0;
}
.cmdbar__index{
  flex:0 0 auto;
  display:grid;
  place-items:center;
  width:34px;
  height:34px;
  border:1px solid rgba(214,64,47,.7);
  background:rgba(214,64,47,.14);
  color:#F08573;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.06em;
}
.brand{
  display:flex;
  flex-direction:column;
  gap:3px;
  min-width:0;
  color:var(--white);
  text-decoration:none;
}
.brand:hover{color:var(--white)}
.brand__name{
  font-family:var(--font-head);
  font-weight:900;
  font-size:16.5px;
  line-height:1.1;
  letter-spacing:.02em;
  white-space:nowrap;
}
.brand__desc{
  font-family:var(--font-mono);
  font-size:10px;
  line-height:1;
  letter-spacing:.16em;
  color:rgba(243,238,229,.55);
  white-space:nowrap;
}

.cmdbar__status{
  display:inline-flex;
  align-items:center;
  gap:9px;
  margin:0;
  padding:5px 11px 5px 9px;
  border:1px solid rgba(46,196,182,.42);
  background:rgba(46,196,182,.1);
  color:#93E6DE;
  font-family:var(--font-mono);
  font-size:11px;
  line-height:1.5;
  letter-spacing:.03em;
  white-space:nowrap;
}
.cmdbar__status-dot{
  flex:0 0 auto;
  width:7px;
  height:7px;
  border-radius:50%;
  background:var(--cyan);
  box-shadow:0 0 0 3px rgba(46,196,182,.18);
}

.nav-toggle{
  display:none;
  align-items:center;
  gap:8px;
  padding:8px 11px;
  background:transparent;
  color:var(--paper);
  border:1px solid rgba(201,194,182,.4);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.12em;
  cursor:pointer;
  transition:border-color var(--dur) var(--ease),background-color var(--dur) var(--ease),color var(--dur) var(--ease);
}
.nav-toggle:hover{border-color:var(--red);color:var(--white)}
.nav-toggle[aria-expanded="true"]{
  background:var(--red);
  border-color:var(--red);
  color:var(--white);
}
.nav-toggle__bars{
  position:relative;
  display:block;
  width:16px;
  height:10px;
}
.nav-toggle__bars::before,
.nav-toggle__bars::after{
  content:"";
  position:absolute;
  left:0;
  width:100%;
  height:2px;
  background:currentColor;
  transition:transform var(--dur) var(--ease);
}
.nav-toggle__bars::before{top:0}
.nav-toggle__bars::after{bottom:0}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before{transform:translateY(4px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after{transform:translateY(-4px) rotate(-45deg)}
.nav-toggle__text{display:inline}

.cmdnav{display:block;margin-left:auto}
.cmdnav__list{display:flex;align-items:stretch;gap:0;margin:0;padding:0;list-style:none}
.cmdnav__item{margin:0}
.cmdnav__link{
  display:flex;
  align-items:baseline;
  gap:5px;
  padding:9px 10px 8px;
  border-bottom:2px solid transparent;
  color:rgba(243,238,229,.74);
  font-family:var(--font-head);
  font-weight:500;
  font-size:13.5px;
  letter-spacing:.02em;
  text-decoration:none;
  white-space:nowrap;
  transition:color var(--dur) var(--ease),background-color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.cmdnav__num{
  font-family:var(--font-mono);
  font-size:9.5px;
  letter-spacing:.08em;
  color:rgba(251,248,241,.38);
  transition:color var(--dur) var(--ease);
}
.cmdnav__label{display:inline}
.cmdnav__link:hover{color:var(--white);background:rgba(251,248,241,.07)}
.cmdnav__link:hover .cmdnav__num{color:var(--cyan)}
.cmdnav__link[aria-current="page"]{color:var(--white);border-bottom-color:var(--red)}
.cmdnav__link[aria-current="page"] .cmdnav__num{color:var(--red)}

.cmdbar__quick{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  padding:8px 14px;
  background:var(--red);
  border:1px solid var(--red);
  color:var(--white);
  font-family:var(--font-head);
  font-weight:700;
  font-size:13px;
  letter-spacing:.02em;
  text-decoration:none;
  white-space:nowrap;
  box-shadow:3px 3px 0 rgba(0,0,0,.35);
  transition:background-color var(--dur) var(--ease),transform var(--dur) var(--ease),box-shadow var(--dur) var(--ease);
}
.cmdbar__quick:hover{
  background:var(--red-deep);
  border-color:var(--red-deep);
  color:var(--white);
  transform:translate(-1px,-1px);
  box-shadow:4px 4px 0 rgba(0,0,0,.42);
}

.progress{
  height:2px;
  background:rgba(201,194,182,.16);
  overflow:hidden;
}
.progress__bar{
  display:block;
  height:100%;
  width:0;
  background:var(--red);
  transition:width 80ms linear;
}

/* ==========================================================================
   页脚
   ========================================================================== */
.site-footer{
  position:relative;
  margin-top:0;
  padding:56px 0 0;
  background:var(--ink);
  color:var(--paper);
  border-top:3px solid var(--red);
  overflow:hidden;
}
.site-footer::before{
  content:"";
  position:absolute;
  inset:0;
  background-image:
    linear-gradient(to right,rgba(201,194,182,.07) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(201,194,182,.07) 1px,transparent 1px);
  background-size:var(--rail) var(--rail);
  pointer-events:none;
}
.footer-shell{position:relative;z-index:1}

.footer-grid{
  display:grid;
  grid-template-columns:1.35fr .85fr .9fr 1.1fr;
  gap:36px 32px;
  padding-bottom:40px;
}

.footer-brand__mark{
  display:flex;
  align-items:center;
  gap:10px;
  margin:0 0 12px;
  font-family:var(--font-head);
  font-weight:900;
  font-size:17px;
  letter-spacing:.02em;
  color:var(--white);
}
.footer-brand__num{
  display:grid;
  place-items:center;
  width:30px;
  height:30px;
  border:1px solid rgba(214,64,47,.7);
  background:rgba(214,64,47,.16);
  color:#F08573;
  font-family:var(--font-mono);
  font-size:10.5px;
  letter-spacing:.06em;
}
.footer-brand__note{
  margin:0 0 16px;
  max-width:26em;
  font-size:14.5px;
  line-height:1.75;
  color:rgba(243,238,229,.66);
}
.footer-brand__status{
  display:inline-flex;
  align-items:center;
  gap:8px;
  margin:0;
  padding:5px 10px;
  border:1px solid rgba(46,196,182,.35);
  background:rgba(46,196,182,.08);
  color:#93E6DE;
  font-family:var(--font-mono);
  font-size:10.5px;
  letter-spacing:.05em;
  line-height:1.6;
}

.footer-col{min-width:0}
.footer-col__title{
  display:flex;
  align-items:baseline;
  gap:8px;
  margin:0 0 14px;
  padding-bottom:10px;
  border-bottom:1px solid rgba(201,194,182,.2);
  font-family:var(--font-head);
  font-weight:700;
  font-size:12.5px;
  letter-spacing:.08em;
  color:rgba(243,238,229,.9);
}
.footer-col__num{
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.1em;
  color:var(--cyan);
}

.footer-links{
  display:grid;
  gap:2px;
  margin:0;
  padding:0;
  list-style:none;
}
.footer-link{
  position:relative;
  display:inline-block;
  padding:4px 0;
  color:rgba(243,238,229,.76);
  font-size:14px;
  line-height:1.6;
  text-decoration:none;
  transition:color var(--dur) var(--ease);
}
.footer-link::after{
  content:"";
  position:absolute;
  left:0;
  bottom:1px;
  width:0;
  height:1px;
  background:var(--red);
  transition:width var(--dur) var(--ease);
}
.footer-link:hover{color:var(--white)}
.footer-link:hover::after,
.footer-link:focus-visible::after{width:100%}

.footer-contact{
  display:grid;
  gap:10px;
  margin:0;
  padding:0;
  list-style:none;
  font-size:14px;
  line-height:1.6;
}
.footer-contact li{display:flex;flex-direction:column;gap:2px}
.footer-contact__key{
  font-family:var(--font-mono);
  font-size:10.5px;
  letter-spacing:.12em;
  color:var(--cyan);
}
.footer-contact__val{
  color:rgba(243,238,229,.82);
  word-break:break-word;
}

.footer-base{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:10px 24px;
  padding:16px 0 22px;
  border-top:1px solid rgba(201,194,182,.2);
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.04em;
  color:rgba(243,238,229,.55);
}
.footer-base__copy,
.footer-base__icp,
.footer-base__note{margin:0}
.footer-base__icp{color:rgba(243,238,229,.72)}

/* ==========================================================================
   响应式
   ========================================================================== */
@media (max-width:1160px){
  .cmdbar__inner{padding:9px 18px;gap:9px 12px}
  .cmdbar__brand{order:1;margin-right:auto}
  .nav-toggle{order:2;display:inline-flex}
  .cmdbar__quick{order:3;padding:7px 12px;font-size:12.5px}
  .cmdbar__status{order:4;flex-basis:100%;white-space:normal}
  .cmdnav{order:5;flex-basis:100%;margin-left:0;display:none}
  .cmdnav[data-open]{display:block}
  .cmdnav__list{
    flex-direction:column;
    align-items:stretch;
    margin-top:2px;
    padding-top:6px;
    border-top:1px solid rgba(201,194,182,.2);
  }
  .cmdnav__link{
    gap:10px;
    padding:12px 6px;
    border-bottom:1px solid rgba(201,194,182,.14);
    font-size:15px;
  }
  .cmdnav__num{font-size:11px}
  .cmdnav__link[aria-current="page"]{
    border-bottom-color:rgba(201,194,182,.14);
    border-left:3px solid var(--red);
    padding-left:12px;
    background:rgba(214,64,47,.12);
  }
  .footer-grid{grid-template-columns:1.3fr 1fr 1fr}
}

@media (max-width:960px){
  .grid--2,.grid--3,.grid--4,.grid--split{grid-template-columns:minmax(0,1fr)}
  .rail{position:static;top:auto;flex-direction:row;flex-wrap:wrap;gap:6px 16px;padding-left:0;border-left:0}
  .footer-grid{grid-template-columns:1fr 1fr}
  .footer-brand{grid-column:1 / -1}
}

@media (max-width:720px){
  body{font-size:16px;line-height:1.75}
  .brand__name{font-size:15px}
  .brand__desc{display:none}
  .cmdbar__index{width:30px;height:30px;font-size:10px}
  .cmdbar__inner{padding:9px 16px;min-height:56px}
  .footer-grid{grid-template-columns:1fr;gap:28px}
  .footer-base{font-size:11px}
  .media-frame--tall{aspect-ratio:4/5}
}

@media (max-width:420px){
  .cmdbar__quick{font-size:12px;padding:6px 10px}
  .nav-toggle{padding:7px 9px;font-size:10.5px}
  .footer-brand__mark{font-size:15.5px}
}

/* ---------- 可达性：减少动态 ---------- */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,
  *::before,
  *::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  .paper-card:hover,
  .btn--primary:hover,
  .cmdbar__quick:hover{
    transform:none;
    box-shadow:var(--shadow-hard);
  }
  .footer-link::after{transition:none}
}