:root{
  --apple:#1F7A63;
  --apple-deep:#145847;
  --apple-mist:#DDEEE7;
  --copper:#B7793C;
  --copper-deep:#8A5626;
  --copper-light:#E9C99C;
  --cream:#F6F0E4;
  --ink:#142A3A;
  --graphite:#3B4A54;
  --paper:#FFFDF8;
  --signal:#A94D3F;

  --serif:"Noto Serif SC","Source Han Serif SC","Songti SC","SimSun",serif;
  --sans:"Noto Sans SC","Source Han Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;

  --r-lg:30px;
  --r-md:18px;
  --r-pill:999px;

  --shell:1200px;
  --edge:clamp(18px,5vw,56px);
  --stack:22px;
}

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

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

body{
  margin:0;
  background:
    radial-gradient(120% 60% at 50% -12%,var(--paper),rgba(255,253,248,0) 58%),
    var(--cream);
  color:var(--ink);
  font-family:var(--sans);
  font-size:clamp(17px,1.05vw,19px);
  line-height:1.8;
  -webkit-font-smoothing:antialiased;
}

h1,h2,h3,h4{
  margin:0;
  font-family:var(--serif);
  font-weight:700;
  line-height:1.16;
  letter-spacing:-.01em;
  color:var(--ink);
}

p{margin:0;}
ul,ol{margin:0;padding:0;list-style:none;}
a{color:inherit;text-decoration:none;}
img{display:block;max-width:100%;height:auto;}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer;}
strong{font-weight:700;color:var(--apple-deep);}

:focus-visible{
  outline:3px solid var(--copper);
  outline-offset:3px;
  border-radius:8px;
}

.skip-link{
  position:fixed;
  left:16px;
  top:-120px;
  z-index:200;
  padding:12px 22px;
  border-radius:var(--r-pill);
  background:var(--ink);
  color:var(--cream);
  font-size:14px;
  letter-spacing:.08em;
  transition:top .2s ease;
}
.skip-link:focus{top:14px;}

/* ---------- 布局基础 ---------- */
.shell{
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding-inline:var(--edge);
}

.section{padding-block:clamp(40px,7vw,88px);}
.section--tight{padding-block:clamp(24px,4vw,48px);}

.stack{display:flex;flex-direction:column;gap:var(--stack);}
.grid{display:grid;gap:clamp(18px,3vw,32px);}
.grid--2{grid-template-columns:repeat(auto-fit,minmax(min(100%,300px),1fr));}
.grid--3{grid-template-columns:repeat(auto-fit,minmax(min(100%,240px),1fr));}

.rule{
  height:1px;
  border:0;
  margin:0;
  background:linear-gradient(90deg,rgba(183,121,60,.6),rgba(183,121,60,0));
}

/* ---------- 堆叠画板 ---------- */
.board{
  position:relative;
  isolation:isolate;
  background:var(--paper);
  border:1px solid rgba(183,121,60,.26);
  border-radius:var(--r-lg);
  padding:clamp(22px,3.6vw,44px);
  box-shadow:0 22px 46px -38px rgba(20,42,58,.9);
}
.board--mist{
  background:var(--apple-mist);
  border-color:rgba(31,122,99,.2);
  box-shadow:0 22px 46px -38px rgba(20,42,58,.55);
}
.board--ink{
  background:var(--ink);
  color:var(--cream);
  border-color:rgba(233,201,156,.3);
}
.board--ink h2,.board--ink h3,.board--ink h4{color:var(--cream);}
.board--flush{padding:0;overflow:hidden;}
.board--stack::after{
  content:"";
  position:absolute;
  left:18px;
  right:18px;
  bottom:-9px;
  height:9px;
  z-index:-1;
  border:1px solid rgba(183,121,60,.24);
  border-top:0;
  border-radius:0 0 16px 16px;
  background:var(--apple-mist);
}

/* ---------- 胶囊与编号 ---------- */
.capsule{
  display:inline-flex;
  align-items:center;
  gap:7px;
  padding:5px 13px;
  border:1px solid transparent;
  border-radius:var(--r-pill);
  font-size:11.5px;
  font-weight:600;
  letter-spacing:.16em;
  text-transform:uppercase;
  line-height:1.5;
  white-space:nowrap;
}
.capsule--copper{background:rgba(233,201,156,.42);color:var(--copper-deep);border-color:rgba(183,121,60,.5);}
.capsule--mist{background:var(--apple-mist);color:var(--apple-deep);border-color:rgba(31,122,99,.32);}
.capsule--ink{background:var(--ink);color:var(--cream);border-color:rgba(233,201,156,.42);}

.num{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  min-width:2.2em;
  padding:.16em .5em;
  border-radius:var(--r-pill);
  background:var(--apple-mist);
  color:var(--apple-deep);
  font-family:var(--sans);
  font-size:.78em;
  font-weight:700;
  font-variant-numeric:tabular-nums;
  letter-spacing:.04em;
}
.num--copper{background:rgba(233,201,156,.55);color:var(--copper-deep);}
.num--ink{background:var(--ink);color:var(--cream);}

/* ---------- 按钮 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:9px;
  padding:13px 26px;
  border:1px solid transparent;
  border-radius:var(--r-pill);
  font-family:var(--sans);
  font-size:15px;
  font-weight:600;
  letter-spacing:.05em;
  line-height:1.25;
  cursor:pointer;
  transition:background-color .18s ease,color .18s ease,border-color .18s ease,box-shadow .18s ease;
}
.btn--apple{background:var(--apple);color:var(--paper);box-shadow:inset 0 0 0 1px rgba(233,201,156,.45);}
.btn--apple:hover{background:var(--apple-deep);box-shadow:inset 0 0 0 1px var(--copper-light),0 14px 26px -20px rgba(20,42,58,.9);}
.btn--copper{background:var(--copper);color:var(--paper);box-shadow:inset 0 0 0 1px rgba(255,253,248,.28);}
.btn--copper:hover{background:var(--copper-deep);}
.btn--ghost{background:transparent;color:var(--ink);border-color:rgba(20,42,58,.28);}
.btn--ghost:hover{background:var(--apple-mist);border-color:var(--apple);color:var(--apple-deep);}
.btn--small{padding:9px 18px;font-size:13.5px;}

/* ---------- 面包屑 / 旁注 / 齿轮 ---------- */
.crumbs{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  font-size:13px;
  letter-spacing:.06em;
  color:var(--graphite);
}
.crumbs li{display:flex;align-items:center;gap:8px;}
.crumbs li + li::before{content:"/";color:var(--copper);font-family:var(--serif);}
.crumbs a{color:var(--graphite);border-bottom:1px solid rgba(183,121,60,.35);transition:color .18s ease,border-color .18s ease;}
.crumbs a:hover{color:var(--apple-deep);border-color:var(--apple-deep);}
.crumbs [aria-current="page"]{color:var(--ink);font-weight:600;border:0;}

.anote{
  writing-mode:vertical-rl;
  font-family:var(--serif);
  font-size:12.5px;
  letter-spacing:.34em;
  line-height:1.2;
  color:var(--graphite);
}
.anote--copper{color:var(--copper);}
.anote--ink{color:var(--ink);}

.cog{
  --cog:96px;
  width:var(--cog);
  aspect-ratio:1;
  border-radius:50%;
  border:1px solid rgba(20,42,58,.12);
  background:
    repeating-conic-gradient(from 0deg,var(--copper) 0 5deg,rgba(183,121,60,0) 5deg 30deg),
    radial-gradient(circle,var(--cream) 0 24%,var(--apple-mist) 25% 52%,var(--apple) 53% 60%,var(--apple-mist) 61% 100%);
}

/* ---------- 图片容器 ---------- */
.media{
  position:relative;
  display:block;
  overflow:hidden;
  border-radius:var(--r-lg);
  border:1px solid rgba(183,121,60,.3);
  background:linear-gradient(150deg,var(--apple-mist),#EDF5F0 55%,var(--copper-light));
  box-shadow:0 24px 44px -36px rgba(20,42,58,.85);
}
.media > img{width:100%;height:100%;object-fit:cover;}
.media--plate{aspect-ratio:4/3;}
.media--wide{aspect-ratio:16/9;}
.media--square{aspect-ratio:1;}
.media--tall{aspect-ratio:3/4;}
.media--empty::after{
  content:"";
  position:absolute;
  inset:0;
  background:
    radial-gradient(72% 58% at 68% 16%,rgba(233,201,156,.8),transparent 72%),
    repeating-linear-gradient(135deg,rgba(255,253,248,.38) 0 10px,rgba(255,253,248,0) 10px 22px);
}
.media__cap{
  position:absolute;
  left:14px;
  right:14px;
  bottom:14px;
  padding:6px 14px;
  border-radius:var(--r-pill);
  border:1px solid rgba(183,121,60,.26);
  background:rgba(255,253,248,.88);
  color:var(--ink);
  font-size:12.5px;
  letter-spacing:.06em;
  line-height:1.6;
}

/* ---------- 折叠面板 ---------- */
.fold{
  border:1px solid rgba(183,121,60,.3);
  border-radius:var(--r-md);
  background:var(--paper);
  overflow:hidden;
}
.fold + .fold{margin-top:10px;}
.fold > summary{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:14px;
  padding:16px 20px;
  cursor:pointer;
  list-style:none;
  font-family:var(--serif);
  font-size:17px;
  font-weight:600;
  transition:background-color .18s ease,color .18s ease;
}
.fold > summary::-webkit-details-marker{display:none;}
.fold > summary::after{
  content:"";
  flex:0 0 auto;
  width:10px;
  height:10px;
  border-right:2px solid var(--copper);
  border-bottom:2px solid var(--copper);
  transform:rotate(45deg);
  transition:transform .22s ease;
}
.fold > summary:hover{background:rgba(221,238,231,.55);}
.fold[open] > summary{background:var(--apple-mist);color:var(--apple-deep);}
.fold[open] > summary::after{transform:rotate(-135deg);}
.fold__body{
  padding:6px 20px 20px;
  font-size:16px;
  line-height:1.8;
  color:var(--graphite);
}

/* ---------- 进度条与提示 ---------- */
.progress{
  position:fixed;
  top:0;
  left:0;
  right:0;
  height:3px;
  z-index:90;
  pointer-events:none;
  transform:scaleX(0);
  transform-origin:0 50%;
  background:linear-gradient(90deg,var(--apple),var(--copper));
  will-change:transform;
}

.toast{
  position:fixed;
  left:50%;
  bottom:26px;
  z-index:150;
  max-width:calc(100% - 32px);
  padding:11px 22px;
  border:1px solid rgba(233,201,156,.45);
  border-radius:var(--r-pill);
  background:var(--ink);
  color:var(--cream);
  font-size:14px;
  letter-spacing:.03em;
  text-align:center;
  opacity:0;
  pointer-events:none;
  transform:translate(-50%,14px);
  transition:opacity .22s ease,transform .22s ease;
}
.toast[data-show="true"]{opacity:1;transform:translate(-50%,0);}

/* ================= 页头 ================= */
.site-head{
  position:sticky;
  top:0;
  z-index:60;
  background:var(--cream);
  border-bottom:1px solid rgba(20,42,58,.12);
  box-shadow:0 12px 30px -28px rgba(20,42,58,.95);
}
.site-head__rail{
  position:relative;
  height:5px;
  background:linear-gradient(90deg,var(--apple-deep),var(--apple) 38%,var(--copper) 78%,var(--copper-light));
}
.site-head__rail::after{
  content:"";
  position:absolute;
  inset:0;
  background:repeating-linear-gradient(90deg,rgba(246,240,228,.85) 0 1px,rgba(246,240,228,0) 1px 14px);
  opacity:.75;
}
.site-head__inner{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:clamp(12px,2.4vw,32px);
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding:14px var(--edge);
}

.brand{
  display:inline-flex;
  align-items:center;
  gap:12px;
  flex:0 0 auto;
  order:1;
}
.brand__mark{
  position:relative;
  flex:0 0 auto;
  width:clamp(38px,3.6vw,46px);
  aspect-ratio:1;
  border-radius:50%;
  background:
    radial-gradient(circle at 50% 50%,var(--paper) 0 28%,var(--apple) 29% 44%,var(--apple-deep) 45% 60%,var(--copper) 61% 72%,rgba(183,121,60,0) 73%),
    repeating-conic-gradient(from 0deg,var(--copper) 0 4deg,rgba(183,121,60,0) 4deg 20deg);
  box-shadow:inset 0 0 0 1px rgba(183,121,60,.5);
  transition:transform .5s ease;
}
.brand:hover .brand__mark{transform:rotate(60deg);}
.brand__text{display:flex;flex-direction:column;line-height:1.2;}
.brand__name{
  font-family:var(--serif);
  font-weight:700;
  font-size:clamp(17px,1.35vw,21px);
  letter-spacing:.05em;
  color:var(--ink);
}
.brand__latin{
  margin-top:3px;
  font-size:10px;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--graphite);
}

.nav-toggle{
  display:none;
  align-items:center;
  gap:10px;
  order:2;
  margin-left:auto;
  padding:10px 16px;
  border:1px solid rgba(31,122,99,.4);
  border-radius:var(--r-pill);
  background:var(--paper);
  color:var(--apple-deep);
  font-size:13px;
  font-weight:600;
  letter-spacing:.14em;
  transition:background-color .18s ease,border-color .18s ease;
}
.nav-toggle:hover{background:var(--apple-mist);border-color:var(--apple);}
.nav-toggle__bars{display:grid;gap:4px;width:18px;}
.nav-toggle__bars > span{
  display:block;
  height:2px;
  border-radius:2px;
  background:currentColor;
  transition:transform .25s ease,opacity .2s ease;
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars > span:first-child{transform:translateY(6px) rotate(45deg);}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars > span:last-child{transform:translateY(-6px) rotate(-45deg);}
.nav-toggle__label{white-space:nowrap;}

.site-nav{
  display:flex;
  align-items:center;
  gap:clamp(8px,1.4vw,20px);
  flex:1 1 auto;
  min-width:0;
  order:3;
}
.site-nav__group{
  display:flex;
  align-items:center;
  gap:clamp(0px,.5vw,8px);
}
.site-nav__group--lead,
.site-nav__group--tail{flex:0 0 auto;}

.site-nav__hinge{
  position:relative;
  flex:1 1 40px;
  min-width:22px;
  height:1px;
  align-self:center;
  background:repeating-linear-gradient(90deg,rgba(20,42,58,.32) 0 6px,rgba(20,42,58,0) 6px 13px);
}
.site-nav__hinge::after{
  content:"";
  position:absolute;
  left:50%;
  top:50%;
  width:6px;
  height:6px;
  margin:-3px 0 0 -3px;
  border-radius:50%;
  background:var(--copper);
}

.site-nav__link{
  position:relative;
  display:inline-flex;
  align-items:baseline;
  gap:6px;
  padding:10px 12px;
  border-radius:var(--r-pill);
  font-size:14.5px;
  color:var(--ink);
  white-space:nowrap;
  transition:color .18s ease,background-color .18s ease;
}
.site-nav__link::after{
  content:"";
  position:absolute;
  left:12px;
  right:12px;
  bottom:7px;
  height:2px;
  border-radius:2px;
  background:var(--copper);
  transform:scaleX(0);
  transform-origin:left center;
  transition:transform .22s ease;
}
.site-nav__link:hover{color:var(--apple-deep);}
.site-nav__link:hover::after{transform:scaleX(1);}
.site-nav__idx{
  font-size:10px;
  font-weight:600;
  letter-spacing:.1em;
  color:var(--copper);
  font-variant-numeric:tabular-nums;
}
.site-nav__link[aria-current="page"]{
  background:var(--apple-mist);
  color:var(--apple-deep);
  font-weight:700;
}
.site-nav__link[aria-current="page"]::after{transform:scaleX(0);}

.site-nav__cta{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  flex:0 0 auto;
  padding:10px 20px;
  border-radius:var(--r-pill);
  background:var(--apple);
  color:var(--paper);
  font-size:13.5px;
  font-weight:600;
  letter-spacing:.1em;
  white-space:nowrap;
  box-shadow:inset 0 0 0 1px rgba(233,201,156,.55);
  transition:background-color .18s ease,box-shadow .18s ease;
}
.site-nav__cta:hover{
  background:var(--apple-deep);
  box-shadow:inset 0 0 0 1px var(--copper),0 12px 22px -18px rgba(20,42,58,.95);
}

/* ================= 页脚 ================= */
.site-foot{
  margin-top:clamp(48px,8vw,96px);
  padding-block:clamp(36px,6vw,72px) 26px;
  background:
    radial-gradient(120% 90% at 84% -20%,rgba(31,122,99,.42),rgba(31,122,99,0) 62%),
    var(--ink);
  color:var(--cream);
}
.site-foot h2,.site-foot h3{color:var(--cream);}

.foot-desk{
  display:grid;
  gap:clamp(16px,2.4vw,22px);
  padding:clamp(22px,3.4vw,40px);
  border:1px solid rgba(233,201,156,.35);
  border-radius:var(--r-lg);
  background:var(--apple-deep);
  box-shadow:0 0 0 6px rgba(20,42,58,.35),inset 0 1px 0 rgba(233,201,156,.22);
}
.foot-desk__head{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:12px 18px;
}
.foot-desk__title{
  font-size:clamp(20px,2.2vw,28px);
  letter-spacing:.02em;
}
.foot-desk__list{
  display:grid;
  grid-template-columns:repeat(auto-fit,minmax(240px,1fr));
  gap:12px;
}
.foot-desk__item{
  display:grid;
  gap:4px;
  padding:14px 18px;
  border:1px solid rgba(233,201,156,.22);
  border-radius:var(--r-md);
  background:rgba(20,42,58,.34);
}
.foot-desk__label{
  font-size:11.5px;
  font-weight:600;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--copper-light);
}
.foot-desk__value{
  padding:0;
  font-family:var(--serif);
  font-size:clamp(18px,1.9vw,23px);
  font-weight:600;
  letter-spacing:.02em;
  line-height:1.4;
  text-align:left;
  color:var(--cream);
  font-variant-numeric:tabular-nums;
  word-break:break-all;
  text-decoration:underline dotted rgba(233,201,156,.55);
  text-underline-offset:5px;
  transition:color .18s ease,text-decoration-color .18s ease;
}
.foot-desk__value:hover{color:var(--copper-light);text-decoration-color:var(--copper-light);}
.foot-desk__actions{display:flex;flex-wrap:wrap;gap:12px;}
.foot-desk__note{
  max-width:54ch;
  font-size:14px;
  line-height:1.75;
  color:rgba(246,240,228,.74);
}
.site-foot .btn--ghost{
  border-color:rgba(233,201,156,.45);
  color:var(--cream);
}
.site-foot .btn--ghost:hover{
  background:rgba(233,201,156,.16);
  border-color:var(--copper-light);
  color:var(--copper-light);
}

.foot-index{
  display:grid;
  grid-template-columns:minmax(0,1.1fr) minmax(0,1fr);
  gap:clamp(20px,4vw,52px);
  margin-top:clamp(28px,5vw,52px);
  padding-top:clamp(24px,4vw,40px);
  border-top:1px solid rgba(233,201,156,.25);
}
.foot-brand__name{
  font-family:var(--serif);
  font-size:clamp(20px,2.3vw,26px);
  font-weight:700;
  letter-spacing:.08em;
  color:var(--cream);
}
.foot-brand__note{
  margin-top:10px;
  max-width:40ch;
  font-size:14.5px;
  line-height:1.78;
  color:rgba(246,240,228,.7);
}
.foot-index__nav{display:grid;align-content:start;gap:0;}
.foot-index__title{
  margin-bottom:12px;
  font-size:11.5px;
  font-weight:600;
  letter-spacing:.22em;
  text-transform:uppercase;
  color:var(--copper-light);
}
.foot-index__list{
  display:grid;
  grid-template-columns:repeat(auto-fit,minmax(140px,1fr));
  gap:8px 20px;
}
.foot-index__list a{
  display:inline-block;
  padding:3px 0;
  font-size:15px;
  color:rgba(246,240,228,.86);
  border-bottom:1px solid transparent;
  transition:color .18s ease,border-color .18s ease;
}
.foot-index__list a:hover{color:var(--copper-light);border-bottom-color:var(--copper);}

.foot-meta{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px 26px;
  margin-top:clamp(24px,4vw,40px);
  padding-top:20px;
  border-top:1px solid rgba(233,201,156,.18);
  font-size:13px;
  line-height:1.7;
  color:rgba(246,240,228,.62);
}
.foot-meta__line{margin:0;}
.foot-meta__links{display:flex;flex-wrap:wrap;gap:8px 18px;}
.foot-meta__links a{
  padding-bottom:2px;
  border-bottom:1px solid rgba(233,201,156,.4);
  transition:color .18s ease,border-color .18s ease;
}
.foot-meta__links a:hover{color:var(--copper-light);border-color:var(--copper-light);}

/* ---------- 目录高亮（页面阶段使用 data-toc-link） ---------- */
[data-toc-link]{transition:color .18s ease,background-color .18s ease;}
[data-toc-link][aria-current="true"]{color:var(--apple-deep);font-weight:700;}

/* ================= 响应式 ================= */
@media (max-width:959px){
  .site-head__inner{padding:12px var(--edge);gap:10px 12px;}
  .nav-toggle{display:inline-flex;}
  .site-nav{
    order:3;
    flex:1 1 100%;
    flex-direction:column;
    align-items:stretch;
    gap:10px;
    max-height:0;
    padding:0;
    overflow:hidden;
    opacity:0;
    transition:max-height .3s ease,opacity .24s ease,padding .3s ease;
  }
  .site-nav[data-open="true"]{
    max-height:min(76vh,560px);
    padding:6px 0 16px;
    opacity:1;
    overflow-y:auto;
  }
  .site-nav__group{
    flex-direction:column;
    align-items:stretch;
    gap:2px;
  }
  .site-nav__hinge{display:none;}
  .site-nav__link{
    display:flex;
    align-items:center;
    gap:10px;
    width:100%;
    padding:13px 14px;
    border-radius:14px;
    font-size:16px;
    white-space:normal;
  }
  .site-nav__link::after{display:none;}
  .site-nav__link[aria-current="page"]{border-radius:14px;}
  .site-nav__cta{
    order:-1;
    width:100%;
    margin-bottom:4px;
    padding:14px 20px;
    font-size:15px;
    letter-spacing:.14em;
  }
  .foot-index{grid-template-columns:minmax(0,1fr);}
}

@media (max-width:560px){
  .brand__latin{letter-spacing:.14em;font-size:9.5px;}
  .brand__mark{width:36px;}
  .nav-toggle{padding:9px 14px;font-size:12px;}
  .media--tall{aspect-ratio:4/5;}
  .foot-desk__value{font-size:17px;}
  .foot-meta{font-size:12px;gap:6px 18px;}
  .board{padding:20px;border-radius:24px;}
  .board--stack::after{left:12px;right:12px;}
  .section{padding-block:clamp(32px,8vw,56px);}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto;}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
}