@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+TC:wght@300;400;500;700&family=Noto+Serif+TC:wght@400;500;600;700&display=swap');

:root{
  --ink:#000000;
  --paper:#ffffff;
  --line:#000000;
  --r:28px;
  --serif:"Noto Serif TC","Songti SC","SimSun",serif;
  --sans:"Noto Sans TC","PingFang TC","Microsoft JhengHei",system-ui,sans-serif;
  --bar:76px;
}

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

html{
  scroll-behavior:smooth;
  scroll-padding-top:calc(var(--bar) + 20px);
  -webkit-text-size-adjust:100%;
}

body{
  margin:0;
  background:var(--paper);
  color:var(--ink);
  font-family:var(--sans);
  font-size:1rem;
  font-weight:400;
  line-height:1.75;
  overflow-x:hidden;
}

h1,h2,h3{font-family:var(--serif);}

a{color:inherit;}

a:focus-visible,
button:focus-visible,
input:focus-visible{
  outline:3px solid var(--ink);
  outline-offset:3px;
}

.skip{
  position:absolute;
  left:1rem;
  top:-4rem;
  z-index:90;
  background:var(--ink);
  color:#fff;
  padding:.8rem 1.2rem;
  border-radius:12px;
  text-decoration:none;
  transition:top .2s linear;
}
.skip:focus{top:.8rem;}

/* 顶栏 */
.bar{
  position:fixed;
  inset:0 0 auto 0;
  z-index:60;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:1rem;
  min-height:var(--bar);
  padding:.6rem clamp(1rem,4vw,2.5rem);
  background:rgba(255,255,255,.95);
  border-bottom:1px solid var(--line);
}

.brand{
  display:inline-flex;
  align-items:center;
  min-height:44px;
  padding:.5rem .2rem;
  font-family:var(--serif);
  font-size:1.15rem;
  font-weight:700;
  letter-spacing:-.04em;
  text-decoration:none;
}

.burger{
  width:56px;
  height:44px;
  display:inline-flex;
  flex-direction:column;
  justify-content:center;
  gap:5px;
  padding:0 14px;
  background:var(--ink);
  color:#fff;
  border:0;
  border-radius:14px;
  cursor:pointer;
}
.burger span{
  display:block;
  height:2px;
  background:#fff;
  transition:transform .25s ease;
}
.burger[aria-expanded="true"] span:nth-child(1){transform:translateY(7px) rotate(45deg);}
.burger[aria-expanded="true"] span:nth-child(2){opacity:0;}
.burger[aria-expanded="true"] span:nth-child(3){transform:translateY(-7px) rotate(-45deg);}

/* 全屏遮罩菜单 */
.panel{
  position:fixed;
  inset:0;
  z-index:70;
  display:flex;
  align-items:center;
  overflow-y:auto;
  padding:clamp(3rem,8vw,5.5rem) clamp(1.2rem,6vw,4rem);
  background:var(--ink);
  color:#fff;
  visibility:hidden;
  transform:translateY(-102%);
  transition:transform .5s cubic-bezier(.72,0,.2,1),visibility .5s;
}
.panel[data-open="true"]{
  visibility:visible;
  transform:none;
}

.panel-inner{
  width:100%;
  max-width:900px;
  margin:0 auto;
}

.panel-kicker{
  display:block;
  font-size:1rem;
  letter-spacing:.3em;
  color:#fff;
  opacity:.7;
  margin-bottom:1.5rem;
}

.panel-list{
  list-style:none;
  margin:0;
  padding:0;
}
.panel-list li{border-top:1px solid #3a3a3a;}
.panel-list li:last-child{border-bottom:1px solid #3a3a3a;}
.panel-list a{
  display:flex;
  align-items:baseline;
  gap:1rem;
  min-height:56px;
  padding:.85rem 0;
  color:#fff;
  text-decoration:none;
  font-family:var(--serif);
  font-size:clamp(1.4rem,4vw,2.4rem);
  font-weight:700;
  line-height:1.2;
  letter-spacing:-.04em;
}
.panel-list a:hover{opacity:.65;}
.panel-list em{
  font-family:var(--sans);
  font-style:normal;
  font-size:1rem;
  font-weight:500;
  opacity:.5;
  letter-spacing:.12em;
}

.panel-note{
  margin:2rem 0 0;
  max-width:46ch;
  font-size:1rem;
  color:#d8d8d8;
}

.panel-close{
  position:absolute;
  top:1rem;
  right:clamp(1rem,4vw,2.5rem);
  min-height:44px;
  padding:.7rem 1.3rem;
  background:transparent;
  color:#fff;
  border:1px solid #fff;
  border-radius:999px;
  font-family:var(--sans);
  font-size:1rem;
  cursor:pointer;
}

/* 骨架 */
main{padding-top:var(--bar);}

.wrap{
  display:grid;
  grid-template-columns:232px minmax(0,1fr);
  align-items:start;
  gap:clamp(1.5rem,4vw,3.5rem);
  max-width:1240px;
  margin:0 auto;
  padding:clamp(1.5rem,4vw,2.5rem) clamp(1rem,4vw,2.5rem) 0;
}

.rail{
  position:sticky;
  top:calc(var(--bar) + 24px);
}
.rail-kicker{
  display:block;
  font-size:1rem;
  font-weight:500;
  letter-spacing:.26em;
}
.rail nav ul{
  list-style:none;
  margin:1rem 0 0;
  padding:0;
}
.rail a{
  display:flex;
  align-items:baseline;
  gap:.6rem;
  min-height:44px;
  padding:.55rem 0;
  border-bottom:1px solid #e5e5e5;
  text-decoration:none;
  font-size:1rem;
  line-height:1.4;
}
.rail a b{
  font-weight:500;
  font-size:1rem;
  opacity:.42;
  letter-spacing:.1em;
}
.rail a:hover{background:#000;color:#fff;}
.rail a.on{
  font-weight:700;
  border-bottom:2px solid #000;
}
.rail a.on b{opacity:1;}
.rail-note{
  margin:1.25rem 0 0;
  font-size:1rem;
  line-height:1.6;
  color:#4a4a4a;
}

.doc{
  grid-column:2;
  min-width:0;
}

/* 首屏 */
.hero{
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:clamp(1rem,2.5vw,1.75rem);
  min-height:70vh;
  margin-bottom:clamp(3rem,8vw,6.5rem);
}

.hero-media{
  position:relative;
  overflow:hidden;
  background:var(--ink);
  border-radius:var(--r);
  min-height:44vh;
}
.hero-media img{
  width:100%;
  height:100%;
  object-fit:cover;
  display:block;
  transform:scale(1.12);
}
.hero-media .mark{
  position:absolute;
  inset:auto 1.25rem 1.25rem 1.25rem;
  margin:0;
  color:#fff;
  font-family:var(--serif);
  font-weight:900;
  font-size:clamp(2rem,4vw,3rem);
  line-height:.95;
  letter-spacing:-.05em;
}
.badge{
  position:absolute;
  top:1rem;
  left:1rem;
  z-index:2;
  padding:.5rem 1.05rem;
  background:var(--paper);
  color:var(--ink);
  border-radius:999px;
  font-size:1rem;
  font-weight:500;
  line-height:1.4;
}

.hero-copy{
  display:flex;
  flex-direction:column;
  justify-content:center;
  align-items:center;
  gap:1.25rem;
  padding:clamp(.5rem,2vw,1.5rem);
  text-align:center;
}

.hero-copy h1{
  margin:0;
  font-size:clamp(2.2rem,6.4vw,5rem);
  font-weight:900;
  line-height:.98;
  letter-spacing:-.05em;
}

.lede{
  margin:0;
  max-width:32ch;
  font-size:1.0625rem;
  line-height:1.7;
  color:#333;
}

.hero-cta{margin:.5rem 0 0;}
.hero-cta a{
  display:inline-flex;
  align-items:center;
  min-height:48px;
  padding:.8rem 1.6rem;
  background:var(--ink);
  color:#fff;
  border-radius:999px;
  text-decoration:none;
  font-weight:500;
  font-size:1rem;
}
.hero-cta a:hover{background:#1c1c1c;}

/* 正文 */
.eyebrow{
  display:block;
  font-family:var(--sans);
  font-size:1rem;
  font-weight:500;
  letter-spacing:.3em;
  margin-bottom:.75rem;
}

.doc h2{
  margin:0 0 1.1rem;
  font-size:clamp(1.8rem,4.2vw,2.9rem);
  font-weight:900;
  line-height:1.05;
  letter-spacing:-.04em;
}
.doc h3{
  margin:2rem 0 .8rem;
  font-size:clamp(1.35rem,2.6vw,1.8rem);
  font-weight:700;
  line-height:1.2;
  letter-spacing:-.03em;
}
.doc p{
  margin:0 0 1.15rem;
  max-width:66ch;
  line-height:1.85;
}
.doc ul,.doc ol{
  max-width:66ch;
  margin:0 0 1.4rem;
  padding-left:1.3rem;
}
.doc li{margin:.4rem 0;line-height:1.8;}

.doc div > section:not(.hero){
  border-top:2px solid var(--line);
  padding:clamp(2.5rem,6vw,5rem) 0;
  scroll-margin-top:calc(var(--bar) + 20px);
}

.doc div > section:not(.hero) h2{
  font-size:clamp(1.9rem,4.6vw,3.2rem);
}

/* 目录卡 */
.toc-lede{
  margin:0 0 1.75rem;
  max-width:52ch;
  color:#333;
}

.toc{
  list-style:none;
  margin:0 0 clamp(2.5rem,7vw,4.5rem);
  padding:0;
  display:grid;
  grid-template-columns:repeat(auto-fit,minmax(210px,1fr));
  gap:.9rem;
}
.toc a{
  display:flex;
  flex-direction:column;
  justify-content:space-between;
  gap:1rem;
  min-height:132px;
  padding:1.4rem;
  background:var(--ink);
  color:#fff;
  border-radius:var(--r);
  text-decoration:none;
  font-family:var(--serif);
  font-size:1.1rem;
  font-weight:700;
  line-height:1.35;
  letter-spacing:-.02em;
}
.toc li:nth-child(even) a{
  background:var(--paper);
  color:var(--ink);
  border:2px solid var(--line);
}
.toc a:hover{transform:translateY(-2px);}
.toc b{
  font-family:var(--sans);
  font-size:1rem;
  font-weight:500;
  opacity:.6;
  letter-spacing:.05em;
}

.tail{
  margin:clamp(2.5rem,6vw,4rem) 0 0;
}
.tail a{
  display:inline-flex;
  align-items:center;
  min-height:48px;
  padding:.85rem 1.6rem;
  border:2px solid var(--line);
  border-radius:999px;
  text-decoration:none;
  font-weight:500;
}
.tail a:hover{background:var(--ink);color:#fff;}

/* 页脚 */
.foot{
  margin-top:clamp(3rem,9vw,6.5rem);
  padding:clamp(2.5rem,6vw,4.5rem) clamp(1rem,4vw,2.5rem) 2.5rem;
  background:var(--ink);
  color:#fff;
  display:grid;
  grid-template-columns:repeat(4,minmax(0,1fr));
  gap:2rem 1.75rem;
}
.foot p{margin:0;}
.fcol{
  font-size:1rem;
  line-height:1.7;
  color:#e2e2e2;
}
.flabel{
  display:block;
  margin-bottom:.6rem;
  color:#fff;
  font-weight:700;
  letter-spacing:.02em;
}
.sub{
  display:flex;
  flex-wrap:wrap;
  gap:.6rem;
  align-content:flex-start;
}
.sub .flabel{flex:0 0 100%;}
.sub-input{
  flex:1 1 120px;
  min-height:44px;
  padding:.6rem .9rem;
  border:1px solid #6d6d6d;
  border-radius:12px;
  background:transparent;
  color:#fff;
  font-family:var(--sans);
  font-size:1rem;
}
.sub-input::placeholder{color:#9a9a9a;}
.sub-btn{
  min-height:44px;
  padding:.6rem 1.2rem;
  border:0;
  border-radius:12px;
  background:#fff;
  color:#000;
  font-family:var(--sans);
  font-size:1rem;
  font-weight:500;
  cursor:pointer;
}

.copy{
  grid-column:1 / 3;
  align-self:center;
  margin-top:1rem !important;
  padding-top:1.25rem;
  border-top:1px solid #3a3a3a;
  font-size:1rem;
  color:#cfcfcf;
}
.back{
  grid-column:3 / 5;
  display:block;
  margin-top:1rem;
  padding-top:1.25rem;
  border-top:1px solid #3a3a3a;
  text-align:right;
  font-size:1rem;
  color:#cfcfcf;
}
.back a{color:#fff;}

/* 动效 */
.has-js .stagger > li{
  opacity:0;
  transform:translateY(14px);
  transition:opacity .5s ease,transform .5s ease;
}
.has-js .stagger > li.in{
  opacity:1;
  transform:none;
}
.has-js .stagger > li:nth-child(2){transition-delay:.05s;}
.has-js .stagger > li:nth-child(3){transition-delay:.1s;}
.has-js .stagger > li:nth-child(4){transition-delay:.15s;}
.has-js .stagger > li:nth-child(5){transition-delay:.2s;}
.has-js .stagger > li:nth-child(6){transition-delay:.25s;}
.has-js .stagger > li:nth-child(7){transition-delay:.3s;}

@media (max-width:900px){
  .wrap{
    grid-template-columns:minmax(0,1fr);
    gap:1.5rem;
  }
  .doc{grid-column:1;}
  .rail{
    position:static;
    grid-column:1;
    padding-bottom:.5rem;
    border-bottom:2px solid var(--line);
  }
  .rail nav ul{
    display:flex;
    gap:.5rem;
    margin-top:.75rem;
    overflow-x:auto;
    padding-bottom:.5rem;
  }
  .rail li{flex:0 0 auto;}
  .rail a{
    border:1px solid var(--line);
    border-radius:999px;
    padding:.55rem 1rem;
    white-space:nowrap;
  }
  .rail-note{display:none;}

  .hero{
    grid-template-columns:1fr;
    min-height:0;
  }
  .hero-copy{order:-1;padding:0 0 .5rem;}
  .hero-media{min-height:32vh;}
  .hero-copy h1{font-size:clamp(2.1rem,9vw,3rem);}

  .foot{grid-template-columns:1fr 1fr;}
  .copy{grid-column:1 / -1;}
  .back{grid-column:1 / -1;text-align:left;}
}

@media (max-width:560px){
  .foot{grid-template-columns:1fr;}
  .toc{grid-template-columns:1fr;}
  .toc a{min-height:104px;}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto;}
  .has-js .stagger > li{
    opacity:1;
    transform:none;
    transition:none;
  }
  .panel,.burger span,.toc a{transition:none;}
  .hero-media img{transform:none;}
}

button[aria-expanded]{min-width:44px;min-height:44px}