:root{
  --ink-navy:#07111F;
  --ink-charcoal:#111820;
  --steel:#1C2B3A;
  --paper:#F0E6D2;
  --silver:#AEB9C6;
  --fog:#F7FAFC;
  --cyan:#35E6C4;
  --orange:#FF6B35;
  --vermilion:#D94A3A;
  --gold:#C9A45C;
  --ink-on-paper:#14202B;

  --font-display:"Noto Serif SC","Source Han Serif SC","Songti SC","STSong",serif;
  --font-body:"Noto Sans SC","Inter","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-data:"IBM Plex Mono","JetBrains Mono","SF Mono",Menlo,Consolas,monospace;
  --font-cond:"Barlow Condensed","Oswald","Noto Sans SC","PingFang SC",system-ui,sans-serif;

  --rail-w:276px;
  --gutter:clamp(18px,4vw,56px);
  --gap:clamp(14px,2vw,28px);
  --maxw:1180px;
  --line:rgba(174,185,198,.22);
  --line-strong:rgba(174,185,198,.4);
  --shadow-hard:8px 8px 0 rgba(0,0,0,.55);
  --shadow-lift:12px 12px 0 rgba(0,0,0,.62);
  --ease:cubic-bezier(.22,.61,.36,1);
}

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

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

body{
  margin:0;
  padding-inline-start:var(--rail-w);
  min-height:100vh;
  background:
    radial-gradient(1100px 620px at 82% -12%, rgba(53,230,196,.07), transparent 62%),
    radial-gradient(900px 520px at 12% 108%, rgba(255,107,53,.06), transparent 60%),
    var(--ink-navy);
  color:var(--fog);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.72;
  font-weight:400;
  -webkit-font-smoothing:antialiased;
}

body.is-nav-open{overflow:hidden;}

main{display:block;}

img{max-width:100%;display:block;}

h1,h2,h3,h4,h5,h6{margin:0;font-weight:700;line-height:1.22;}
p{margin:0;}
ul,ol{margin:0;padding:0;}
a{color:var(--cyan);text-decoration-thickness:1px;text-underline-offset:3px;}
button{font:inherit;}
hr{border:0;border-top:1px solid var(--line);margin:0;}

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

.skip-link{
  position:fixed;
  left:50%;
  top:0;
  z-index:200;
  transform:translate(-50%,-160%);
  padding:12px 22px;
  background:var(--paper);
  color:var(--ink-on-paper);
  font-family:var(--font-body);
  font-size:14px;
  font-weight:800;
  letter-spacing:.04em;
  text-decoration:none;
  border:2px solid #0B1420;
  box-shadow:4px 4px 0 var(--orange);
  transition:transform .18s var(--ease);
}
.skip-link:focus{transform:translate(-50%,12px);}

/* ============ 侧边轨道导航 ============ */
.rail{
  position:fixed;
  top:0;
  bottom:0;
  left:0;
  z-index:80;
  width:var(--rail-w);
  display:flex;
  flex-direction:column;
  gap:20px;
  padding:26px 22px 18px;
  overflow-y:auto;
  overflow-x:hidden;
  background:linear-gradient(180deg,#0A1523 0%,#07111F 45%,#0A1523 100%);
  border-inline-end:2px solid rgba(174,185,198,.16);
  box-shadow:14px 0 40px rgba(0,0,0,.35);
  transition:transform .3s var(--ease);
}

.rail__brand{flex:0 0 auto;}

.brand{
  display:flex;
  flex-direction:column;
  align-items:flex-start;
  gap:2px;
  text-decoration:none;
  color:inherit;
}

.brand__mark{
  display:grid;
  place-items:center;
  width:40px;
  height:40px;
  margin-block-end:12px;
  background:var(--paper);
  color:var(--ink-navy);
  font-family:var(--font-display);
  font-size:15px;
  font-weight:700;
  letter-spacing:.06em;
  box-shadow:4px 4px 0 var(--orange);
  transition:transform .18s var(--ease),box-shadow .18s var(--ease);
}
.brand:hover .brand__mark{transform:translate(-2px,-2px);box-shadow:6px 6px 0 var(--orange);}

.brand__name{
  font-family:var(--font-cond);
  font-size:20px;
  font-weight:800;
  letter-spacing:.03em;
  line-height:1.1;
  color:var(--fog);
}
.brand__sub{
  font-family:var(--font-data);
  font-size:9.5px;
  letter-spacing:.24em;
  color:var(--silver);
  text-transform:uppercase;
  margin-block-start:4px;
}

.rail__meta{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  padding:9px 11px;
  background:rgba(28,43,58,.7);
  border:1px solid var(--line);
  font-family:var(--font-data);
  font-size:10px;
  letter-spacing:.1em;
  line-height:1.4;
}
.status-dot{
  width:7px;
  height:7px;
  flex:0 0 auto;
  border-radius:50%;
  background:var(--cyan);
  box-shadow:0 0 0 3px rgba(53,230,196,.16);
}
.rail__season{color:var(--fog);font-weight:700;}
.rail__state{color:var(--cyan);}

.rail__nav{flex:1 1 auto;min-height:0;}

.nav-list{
  list-style:none;
  display:flex;
  flex-direction:column;
}

.nav-link{
  position:relative;
  display:grid;
  grid-template-columns:32px 1fr;
  align-items:center;
  gap:8px;
  min-height:44px;
  padding:11px 8px 11px 0;
  border-top:1px solid rgba(174,185,198,.1);
  color:var(--silver);
  text-decoration:none;
  transition:color .18s var(--ease),background .18s var(--ease),padding .18s var(--ease);
}
.nav-list li:last-child .nav-link{border-bottom:1px solid rgba(174,185,198,.1);}

.nav-link::before{
  content:"";
  position:absolute;
  left:-22px;
  top:50%;
  width:3px;
  height:0;
  transform:translateY(-50%);
  background:var(--cyan);
  transition:height .2s var(--ease);
}

.nav-link__num{
  font-family:var(--font-data);
  font-size:10.5px;
  letter-spacing:.08em;
  color:rgba(174,185,198,.5);
  transition:color .18s var(--ease);
}
.nav-link__label{
  font-size:14.5px;
  letter-spacing:.02em;
  line-height:1.3;
}

.nav-link:hover{
  color:var(--fog);
  background:rgba(53,230,196,.06);
  padding-inline-start:8px;
}
.nav-link:hover::before{height:20px;}

.nav-link[aria-current="page"]{
  color:var(--fog);
  background:rgba(53,230,196,.09);
  padding-inline-start:8px;
}
.nav-link[aria-current="page"]::before{height:24px;}
.nav-link[aria-current="page"] .nav-link__num{color:var(--cyan);}
.nav-link[aria-current="page"] .nav-link__label{font-weight:800;}

.rail__foot{
  flex:0 0 auto;
  display:flex;
  flex-direction:column;
  gap:8px;
  padding-block-start:16px;
  border-top:1px solid rgba(174,185,198,.16);
}

.rail__ios{
  display:flex;
  align-items:center;
  justify-content:center;
  min-height:44px;
  padding:12px 14px;
  background:var(--orange);
  color:#140A05;
  font-family:var(--font-body);
  font-size:13.5px;
  font-weight:800;
  letter-spacing:.05em;
  text-decoration:none;
  box-shadow:4px 4px 0 rgba(0,0,0,.55);
  transition:transform .18s var(--ease),box-shadow .18s var(--ease);
}
.rail__ios:hover{transform:translate(-2px,-2px);box-shadow:7px 7px 0 rgba(0,0,0,.6);}

.rail__note{
  font-family:var(--font-data);
  font-size:10px;
  letter-spacing:.1em;
  color:var(--silver);
}

.rail__progress{
  flex:0 0 auto;
  height:2px;
  background:rgba(174,185,198,.16);
  overflow:hidden;
}
.rail__progress-bar{
  display:block;
  width:100%;
  height:100%;
  background:linear-gradient(90deg,var(--cyan),var(--orange));
  transform:scaleX(0);
  transform-origin:left center;
}

/* ============ 移动端条与抽屉 ============ */
.mobile-bar,
.nav-scrim{display:none;}

.nav-toggle{
  display:inline-flex;
  align-items:center;
  gap:10px;
  min-height:44px;
  padding:10px 14px;
  background:transparent;
  color:var(--fog);
  border:2px solid var(--line-strong);
  font-family:var(--font-cond);
  font-size:13px;
  font-weight:700;
  letter-spacing:.16em;
  cursor:pointer;
  transition:border-color .18s var(--ease),color .18s var(--ease),background .18s var(--ease);
}
.nav-toggle:hover{border-color:var(--cyan);color:var(--cyan);}

.nav-toggle__bars{
  position:relative;
  display:block;
  width:18px;
  height:2px;
  background:currentColor;
  transition:background .18s var(--ease);
}
.nav-toggle__bars::before,
.nav-toggle__bars::after{
  content:"";
  position:absolute;
  left:0;
  width:18px;
  height:2px;
  background:currentColor;
  transition:top .2s var(--ease),transform .2s var(--ease);
}
.nav-toggle__bars::before{top:-6px;}
.nav-toggle__bars::after{top:6px;}

.site-header[data-open] .nav-toggle__bars{background:transparent;}
.site-header[data-open] .nav-toggle__bars::before{top:0;transform:rotate(45deg);}
.site-header[data-open] .nav-toggle__bars::after{top:0;transform:rotate(-45deg);}

@media (max-width:1024px){
  :root{--rail-w:0px;}

  .mobile-bar{
    position:sticky;
    top:0;
    z-index:70;
    display:flex;
    align-items:center;
    justify-content:space-between;
    gap:16px;
    padding:11px var(--gutter);
    background:rgba(7,17,31,.94);
    border-bottom:2px solid rgba(174,185,198,.2);
    backdrop-filter:blur(10px);
  }

  .brand--mobile{
    flex-direction:row;
    align-items:center;
    gap:10px;
  }
  .brand--mobile .brand__mark{
    width:32px;
    height:32px;
    margin-block-end:0;
    font-size:12.5px;
    box-shadow:3px 3px 0 var(--orange);
  }
  .brand--mobile .brand__name{font-size:17px;}
  .brand--mobile .brand__sub{display:none;}

  .rail{
    width:min(86vw,320px);
    transform:translateX(-100%);
    border-inline-end:2px solid rgba(53,230,196,.28);
    box-shadow:24px 0 64px rgba(0,0,0,.65);
  }
  .site-header[data-open] .rail{transform:translateX(0);}

  .nav-scrim{
    display:block;
    position:fixed;
    inset:0;
    z-index:60;
    background:rgba(7,17,31,.82);
    opacity:0;
    pointer-events:none;
    transition:opacity .26s var(--ease);
  }
  .site-header[data-open] .nav-scrim{opacity:1;pointer-events:auto;}

  .nav-link{min-height:48px;padding-block:13px;}
}

@media (min-width:1025px){
  .mobile-bar,
  .nav-scrim{display:none;}
}

/* ============ 通用容器与网格 ============ */
.container{
  width:100%;
  max-width:var(--maxw);
  margin-inline:auto;
  padding-inline:var(--gutter);
}
.container--wide{max-width:1360px;}

.grid{
  display:grid;
  grid-template-columns:repeat(12,minmax(0,1fr));
  gap:var(--gap);
}
.u-span-2{grid-column:span 2;}
.u-span-3{grid-column:span 3;}
.u-span-4{grid-column:span 4;}
.u-span-5{grid-column:span 5;}
.u-span-6{grid-column:span 6;}
.u-span-7{grid-column:span 7;}
.u-span-8{grid-column:span 8;}
.u-span-9{grid-column:span 9;}
.u-span-10{grid-column:span 10;}
.u-span-12{grid-column:span 12;}
.u-span-full{grid-column:1/-1;}

@media (max-width:760px){
  .grid{grid-template-columns:1fr;}
  .u-span-2,.u-span-3,.u-span-4,.u-span-5,.u-span-6,
  .u-span-7,.u-span-8,.u-span-9,.u-span-10,.u-span-12{grid-column:1/-1;}
}

/* ============ 按钮 ============ */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:10px;
  min-height:48px;
  padding:12px 22px;
  font-family:var(--font-body);
  font-size:14.5px;
  font-weight:800;
  letter-spacing:.04em;
  line-height:1.2;
  text-decoration:none;
  border:2px solid transparent;
  border-radius:2px;
  cursor:pointer;
  transition:transform .18s var(--ease),box-shadow .18s var(--ease),background .18s var(--ease),color .18s var(--ease),border-color .18s var(--ease);
}
.btn--primary{
  background:var(--orange);
  color:#140A05;
  box-shadow:5px 5px 0 rgba(0,0,0,.55);
}
.btn--primary:hover{transform:translate(-2px,-2px);box-shadow:8px 8px 0 rgba(0,0,0,.6);}
.btn--ghost{
  background:transparent;
  color:var(--cyan);
  border-color:var(--cyan);
}
.btn--ghost:hover{background:rgba(53,230,196,.1);transform:translate(-2px,-2px);box-shadow:6px 6px 0 rgba(53,230,196,.22);}
.btn--paper{
  background:var(--paper);
  color:var(--ink-on-paper);
  box-shadow:5px 5px 0 rgba(0,0,0,.55);
}
.btn--paper:hover{transform:translate(-2px,-2px);box-shadow:8px 8px 0 rgba(0,0,0,.6);}

/* ============ 面包屑 ============ */
.breadcrumb{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  list-style:none;
  font-family:var(--font-data);
  font-size:11px;
  letter-spacing:.1em;
  color:var(--silver);
}
.breadcrumb__item{
  display:inline-flex;
  align-items:center;
  gap:8px;
}
.breadcrumb__item a{
  color:var(--silver);
  text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color .18s var(--ease),border-color .18s var(--ease);
}
.breadcrumb__item a:hover{color:var(--cyan);border-bottom-color:var(--cyan);}
.breadcrumb__sep{color:rgba(174,185,198,.42);}
.breadcrumb__current{color:var(--fog);}

/* ============ 编号章节 ============ */
.chapter{
  display:grid;
  grid-template-columns:auto 1fr;
  gap:clamp(12px,2vw,26px);
  align-items:start;
  margin-block-end:clamp(18px,3vw,32px);
}
.chapter__num{
  font-family:var(--font-display);
  font-size:clamp(38px,5.6vw,74px);
  font-weight:700;
  line-height:.86;
  letter-spacing:-.02em;
  color:var(--cyan);
}
.chapter__title{
  font-family:var(--font-body);
  font-size:clamp(18px,2.3vw,26px);
  font-weight:800;
  letter-spacing:.01em;
  color:var(--fog);
}
.chapter__note{
  margin-block-start:8px;
  max-width:62ch;
  font-size:14.5px;
  line-height:1.7;
  color:var(--silver);
}

/* ============ 图片容器基础规则 ============ */
.figure{
  display:flex;
  flex-direction:column;
  gap:10px;
  margin:0;
}
.figure__media{
  position:relative;
  overflow:hidden;
  border:2px solid var(--line-strong);
  box-shadow:var(--shadow-hard);
  background:
    repeating-linear-gradient(135deg,#16232F 0 12px,#1C2B3A 12px 24px);
}
.figure__img{
  display:block;
  width:100%;
  height:auto;
  object-fit:cover;
  aspect-ratio:16/10;
}
.figure--wide .figure__img{aspect-ratio:21/9;}
.figure--tall .figure__img{aspect-ratio:3/4;}
.figure--square .figure__img{aspect-ratio:1/1;}
.figure__caption{
  font-family:var(--font-data);
  font-size:11.5px;
  letter-spacing:.06em;
  color:var(--silver);
}
.figure__badge{
  position:absolute;
  top:12px;
  left:12px;
  z-index:2;
  padding:5px 10px;
  background:var(--paper);
  color:var(--ink-on-paper);
  font-family:var(--font-data);
  font-size:10.5px;
  font-weight:700;
  letter-spacing:.1em;
}

/* ============ 专题研究板 ============ */
.board{
  padding:clamp(18px,2.4vw,26px);
  background:rgba(28,43,58,.72);
  border:2px solid var(--line);
  box-shadow:6px 6px 0 rgba(0,0,0,.42);
}
.board--paper{
  background:var(--paper);
  color:var(--ink-on-paper);
  border-color:#0B1420;
  box-shadow:8px 8px 0 rgba(0,0,0,.5);
}
.board__head{
  display:flex;
  align-items:baseline;
  justify-content:space-between;
  gap:12px;
  padding-block-end:12px;
  margin-block-end:12px;
  border-bottom:1px solid var(--line);
}
.board--paper .board__head{border-bottom-color:rgba(20,32,43,.2);}
.board__title{
  font-family:var(--font-cond);
  font-size:12.5px;
  font-weight:800;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--cyan);
}
.board--paper .board__title{color:#8A4A1E;}
.board__row{
  display:grid;
  grid-template-columns:minmax(72px,.9fr) 1.6fr;
  gap:12px;
  padding-block:9px;
  border-bottom:1px dashed rgba(174,185,198,.18);
}
.board__row:last-child{border-bottom:0;padding-block-end:0;}
.board__term{
  font-family:var(--font-data);
  font-size:11.5px;
  letter-spacing:.06em;
  color:var(--silver);
}
.board--paper .board__term{color:#5C6B7A;}
.board__def{font-size:14px;line-height:1.68;}

/* ============ 标签与强调 ============ */
.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:4px 9px;
  font-family:var(--font-data);
  font-size:10.5px;
  letter-spacing:.1em;
  text-transform:uppercase;
  border:1px solid currentColor;
}
.tag--cyan{color:var(--cyan);background:rgba(53,230,196,.1);}
.tag--orange{color:var(--orange);background:rgba(255,107,53,.1);}
.tag--red{color:var(--vermilion);background:rgba(217,74,58,.12);}
.tag--gold{color:var(--gold);background:rgba(201,164,92,.12);}
.tag--silver{color:var(--silver);background:rgba(174,185,198,.1);}

.hl-cyan{color:var(--cyan);}
.hl-orange{color:var(--orange);}
.num{
  font-family:var(--font-data);
  font-variant-numeric:tabular-nums;
  letter-spacing:.02em;
}

/* ============ 渐显 ============ */
.js [data-reveal]{
  opacity:0;
  transform:translateY(14px);
  transition:opacity .5s var(--ease),transform .5s var(--ease);
}
.js [data-reveal].is-visible{
  opacity:1;
  transform:none;
}

/* ============ 页脚 ============ */
.site-footer{
  position:relative;
  margin-block-start:clamp(56px,9vw,120px);
  background:var(--ink-charcoal);
  border-top:2px solid rgba(174,185,198,.2);
}
.site-footer::before{
  content:"";
  position:absolute;
  inset-inline:0;
  top:0;
  height:10px;
  background:repeating-linear-gradient(90deg,var(--line-strong) 0 1px,transparent 1px 28px);
  opacity:.5;
  pointer-events:none;
}

.footer__inner{
  width:100%;
  max-width:var(--maxw);
  margin-inline:auto;
  padding:clamp(38px,6vw,72px) var(--gutter) 26px;
}

.footer__masthead{
  display:flex;
  flex-wrap:wrap;
  align-items:baseline;
  justify-content:space-between;
  gap:10px 24px;
  padding-block-end:20px;
  margin-block-end:clamp(26px,4vw,44px);
  border-bottom:2px solid rgba(174,185,198,.2);
}
.footer__wordmark{
  font-family:var(--font-display);
  font-size:clamp(28px,4.6vw,52px);
  font-weight:700;
  line-height:1;
  letter-spacing:.02em;
  color:var(--paper);
}
.footer__tagline{
  font-family:var(--font-data);
  font-size:11px;
  letter-spacing:.22em;
  text-transform:uppercase;
  color:var(--silver);
}

.footer__grid{
  display:grid;
  grid-template-columns:minmax(150px,1fr) minmax(260px,1.25fr) minmax(150px,1fr);
  gap:clamp(24px,4vw,56px);
  align-items:start;
}

.footer__col{min-width:0;}

.footer__heading{
  margin-block-end:14px;
  font-family:var(--font-data);
  font-size:10.5px;
  font-weight:700;
  letter-spacing:.24em;
  text-transform:uppercase;
  color:var(--silver);
}

.footer__list{
  list-style:none;
  display:flex;
  flex-direction:column;
  gap:2px;
}

.footer__link{
  position:relative;
  display:inline-block;
  padding:7px 0;
  color:var(--fog);
  font-size:14.5px;
  line-height:1.4;
  text-decoration:none;
  transition:color .2s var(--ease),padding-left .2s var(--ease);
}
.footer__link::before{
  content:"";
  position:absolute;
  left:0;
  top:50%;
  width:0;
  height:2px;
  background:var(--cyan);
  transform:translateY(-50%);
  transition:width .22s var(--ease);
}
.footer__link:hover{color:var(--cyan);padding-left:18px;}
.footer__link:hover::before{width:12px;}

.footer__card{
  padding:clamp(20px,2.4vw,28px);
  background:var(--paper);
  color:var(--ink-on-paper);
  border:2px solid #0B1420;
  box-shadow:8px 8px 0 rgba(53,230,196,.18);
}
.footer__card-title{
  margin-block-end:14px;
  font-family:var(--font-cond);
  font-size:12.5px;
  font-weight:800;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:#4A5B6C;
}
.footer__contact{
  display:grid;
  grid-template-columns:46px 1fr;
  gap:10px;
  align-items:baseline;
  padding-block:9px;
  border-top:1px solid rgba(20,32,43,.16);
}
.footer__contact:first-of-type{border-top:0;padding-block-start:0;}
.footer__label{
  font-family:var(--font-data);
  font-size:10px;
  letter-spacing:.16em;
  color:#5C6B7A;
}
.footer__value{
  font-family:var(--font-data);
  font-size:13.5px;
  font-weight:600;
  line-height:1.55;
  color:var(--ink-on-paper);
  word-break:break-word;
}
.footer__note{
  margin-block-start:12px;
  font-size:12.5px;
  line-height:1.65;
  color:#33465A;
}

.footer__feedback{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  min-height:44px;
  margin-block-start:18px;
  padding:11px 20px;
  background:var(--orange);
  color:#140A05;
  font-size:13px;
  font-weight:800;
  letter-spacing:.05em;
  text-decoration:none;
  box-shadow:4px 4px 0 rgba(0,0,0,.5);
  transition:transform .18s var(--ease),box-shadow .18s var(--ease);
}
.footer__feedback:hover{transform:translate(-2px,-2px);box-shadow:7px 7px 0 rgba(0,0,0,.55);}

.footer__bar{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:10px 20px;
  margin-block-start:clamp(28px,4vw,48px);
  padding-block-start:18px;
  border-top:1px solid rgba(174,185,198,.16);
  font-family:var(--font-data);
  font-size:11.5px;
  letter-spacing:.06em;
  color:var(--silver);
}
.footer__legal,
.footer__meta{margin:0;}
.footer__icp{color:var(--silver);}

@media (max-width:900px){
  .footer__grid{grid-template-columns:1fr 1fr;}
  .footer__col--card{grid-column:1/-1;}
}
@media (max-width:560px){
  .footer__grid{grid-template-columns:1fr;}
  .footer__masthead{flex-direction:column;align-items:flex-start;}
  .footer__bar{flex-direction:column;align-items:flex-start;}
}

/* ============ 减弱动效 ============ */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto;}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  .js [data-reveal]{opacity:1;transform:none;}
  .rail{transition:none;}
  .footer__link:hover{padding-left:0;}
  .footer__link:hover::before{width:0;}
}