@import url('https://fonts.googleapis.com/css2?family=Inter:ital,wght@0,400;0,500;0,600;0,700;0,800;1,400&family=JetBrains+Mono:wght@400&family=Playfair+Display:ital@1&display=swap');

:root{
  --ink:#111014;
  --ink2:#191820;
  --red:#E4432C;
  --paper:#F3EFE9;
  --line:rgba(243,239,233,.15);
  --muted:rgba(243,239,233,.72);
  --rail:236px;
  --r:28px;
}

*{box-sizing:border-box}
html{overflow-x:hidden;scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  margin:0;
  padding-left:var(--rail);
  background:var(--ink);
  color:var(--paper);
  font-family:Inter,-apple-system,"PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  font-size:17px;
  line-height:1.85;
}
img{max-width:100%}
a{color:inherit}

/* 背景分层 */
.layer{position:fixed;pointer-events:none;z-index:0;will-change:transform}
.l-red{
  top:-20vh;left:-10vw;right:-10vw;height:150vh;
  background:
    radial-gradient(46vw 46vw at 76% 16%,rgba(228,67,44,.34),transparent 70%),
    radial-gradient(38vw 38vw at 12% 72%,rgba(228,67,44,.15),transparent 72%);
}
.l-grid{
  top:-30vh;left:0;right:0;height:170vh;
  background-image:radial-gradient(rgba(243,239,233,.11) 1px,transparent 1px);
  background-size:24px 24px;
  opacity:.5;
}
.l-vig{inset:0;background:radial-gradient(120vw 100vh at 50% 30%,transparent 42%,rgba(6,6,8,.62) 100%)}

/* 左侧固定竖排导航 */
.rail{
  position:fixed;top:0;left:0;bottom:0;width:var(--rail);z-index:50;
  display:flex;flex-direction:column;justify-content:space-between;gap:22px;
  padding:22px 18px 26px;
  border-right:1px solid var(--line);
  background:rgba(17,16,20,.82);
  backdrop-filter:blur(10px);
  -webkit-backdrop-filter:blur(10px);
}
.brand{
  display:inline-flex;align-items:center;justify-content:center;
  width:46px;height:46px;flex:0 0 auto;
  border-radius:16px;background:var(--red);color:var(--paper);
  text-decoration:none;overflow:hidden;
  transition:transform .25s ease,border-radius .25s ease;
}
.brand:hover,.brand:focus-visible{transform:translateY(-2px);border-radius:20px}
.brand img{width:100%;height:100%;object-fit:cover;display:block}
.mark-txt{font-weight:800;font-size:1.15rem;letter-spacing:.06em}

.rail nav{min-width:0}
.rail nav p{display:inline-flex;flex-direction:column;gap:2px;margin:0}
.rail nav a{
  display:flex;align-items:center;min-height:44px;padding:6px 10px;
  color:var(--muted);text-decoration:none;font-size:.96rem;line-height:1.4;
  border-radius:12px;border-left:2px solid transparent;
  transition:color .2s,background .2s,border-color .2s,transform .2s;
}
.rail nav a:hover,.rail nav a:focus-visible{
  color:var(--paper);background:rgba(243,239,233,.07);
  border-left-color:var(--red);transform:translateX(3px);
}

.cta{
  display:flex;align-items:center;justify-content:center;
  min-height:46px;padding:12px 14px;border-radius:999px;
  background:var(--red);color:var(--paper);text-decoration:none;
  font-weight:600;font-size:.95rem;letter-spacing:.04em;text-align:center;
  box-shadow:0 14px 34px -18px rgba(228,67,44,.9);
  transition:transform .2s ease,box-shadow .2s ease;
}
.cta:hover,.cta:focus-visible{transform:translateY(-3px);box-shadow:0 20px 40px -18px rgba(228,67,44,1)}

/* 主体网格：正文左、目录右 */
main{
  position:relative;z-index:1;
  display:grid;grid-template-columns:minmax(0,1fr) 226px;
  column-gap:40px;
  max-width:1240px;margin:0 auto;padding:0 44px 20px;
}
main > *:not(aside){grid-column:1}
main > aside{grid-column:2;grid-row:2 / span 30;align-self:start;position:sticky;top:92px}

/* 首屏 */
main > section.hero{
  grid-column:1 / -1;
  min-height:70vh;
  display:flex;align-items:center;justify-content:flex-end;
  gap:clamp(20px,5vw,64px);
  padding:100px 0 68px;
  position:relative;
}
.hero-copy{text-align:right;max-width:760px;min-width:0}
h1{
  margin:0 0 18px;
  font-family:"Playfair Display",Georgia,"Songti SC","SimSun",serif;
  font-style:italic;font-weight:700;
  font-size:clamp(2.4rem,6.4vw,5.2rem);
  line-height:1.05;letter-spacing:-.01em;
}
h1::after{content:"";display:block;width:96px;height:3px;background:var(--red);margin:22px 0 0 auto}
.hero-lede{margin:0 0 0 auto;max-width:44ch;color:var(--muted);font-size:1.02rem}

.hero-art{
  position:relative;flex:0 0 auto;margin:0;
  width:clamp(120px,16vw,200px);aspect-ratio:3 / 4;
  border-radius:var(--r);overflow:hidden;
  background:linear-gradient(160deg,rgba(228,67,44,.92),rgba(228,67,44,.22));
  box-shadow:0 30px 70px -30px rgba(228,67,44,.7);
}
.hero-art .hero-img{width:100%;height:100%;object-fit:cover;display:block;position:relative;z-index:2}
.art-layer{position:absolute;inset:0;pointer-events:none}
.art-layer.a{background-image:radial-gradient(rgba(17,16,20,.55) 1px,transparent 1px);background-size:14px 14px;z-index:1}
.art-layer.b{background:linear-gradient(180deg,transparent 44%,rgba(17,16,20,.62));z-index:1}

/* 右侧目录 */
aside.toc{
  border:1px solid var(--line);border-radius:var(--r);
  padding:20px 16px;background:rgba(243,239,233,.04);
  backdrop-filter:blur(4px);
}
aside.toc h2{
  margin:0 0 12px;font-size:1rem;font-weight:600;
  letter-spacing:.16em;color:rgba(243,239,233,.55);
}
aside.toc h2 span{border-bottom:0;padding-bottom:0}
aside.toc p{display:flex;flex-direction:column;gap:2px;margin:0}
aside.toc a{
  display:flex;align-items:center;min-height:40px;padding:4px 8px;
  border-radius:10px;color:var(--muted);text-decoration:none;font-size:1rem;line-height:1.45;
  transition:color .2s,background .2s;
}
aside.toc a:hover,aside.toc a:focus-visible{color:var(--paper);background:rgba(243,239,233,.08)}

/* 正文章节卡 */
main > section:not(.hero){
  scroll-margin-top:100px;
  margin:0 0 28px;
  padding:38px 34px;
  border:1px solid var(--line);
  border-bottom:3px solid var(--red);
  border-radius:var(--r);
  background:linear-gradient(180deg,rgba(243,239,233,.055),rgba(243,239,233,.015));
  overflow:hidden;
}
main > section:not(.hero) > :first-child{margin-top:0}
main > section:not(.hero) h2{
  font-size:clamp(1.35rem,2.2vw,1.75rem);line-height:1.35;
  margin:0 0 16px;letter-spacing:-.005em;
}
main > section:not(.hero) h3{font-size:1.15rem;line-height:1.5;margin:26px 0 10px}
main section h2 span,main section h3 span{
  display:inline-block;padding-bottom:4px;
  border-bottom:2px solid rgba(228,67,44,.85);
}
main > section p{margin:0 0 1em;color:rgba(243,239,233,.86)}
main > section ul,main > section ol{padding-left:1.3em;margin:0 0 1em;color:rgba(243,239,233,.86)}
main > section li{margin:.25em 0}
main > section a{color:var(--paper);text-decoration-color:var(--red);text-underline-offset:3px}
main > section img{border-radius:18px;height:auto}
main section figure{margin:22px 0}
main section blockquote{
  margin:22px 0;padding:6px 0 6px 20px;
  border-left:3px solid var(--red);color:var(--muted);
}

/* 页脚：仅 p + small */
footer{
  position:relative;z-index:1;
  max-width:1240px;margin:44px auto 0;
  padding:40px 44px 46px;
  border-top:1px solid var(--line);
  display:grid;grid-template-columns:repeat(3,minmax(0,1fr));
  gap:24px 32px;
  font-size:.95rem;color:var(--muted);
}
footer p{margin:0}
footer .f-brand strong{color:var(--paper);font-weight:700;letter-spacing:.04em}
footer .f-brand{line-height:1.75}
footer .f-links{display:flex;flex-wrap:wrap;gap:2px 16px}
footer .f-links a{
  display:inline-flex;align-items:center;min-height:40px;
  text-decoration:none;color:var(--muted);
  border-bottom:1px solid transparent;transition:color .2s,border-color .2s;
}
footer .f-links a:hover,footer .f-links a:focus-visible{color:var(--paper);border-bottom-color:var(--red)}
footer .f-top a{
  display:inline-flex;align-items:center;min-height:44px;padding:0 18px;
  border:1px solid var(--line);border-radius:999px;
  text-decoration:none;color:var(--paper);font-size:.95rem;
  transition:border-color .2s,background .2s;
}
footer .f-top a:hover,footer .f-top a:focus-visible{border-color:var(--red);background:rgba(228,67,44,.14)}
footer small{
  grid-column:1 / -1;display:block;text-align:center;
  margin-top:8px;padding-top:18px;
  border-top:1px solid var(--line);
  color:rgba(243,239,233,.5);
}

/* 滚动显现 */
.rv{opacity:0;transform:translateY(26px);transition:opacity .8s ease,transform .8s cubic-bezier(.2,.72,.2,1)}
.rv.in{opacity:1;transform:none}

@media (max-width:1100px){
  main{grid-template-columns:minmax(0,1fr) 200px;column-gap:28px;padding:0 30px 20px}
  footer{padding:36px 30px 42px}
  main > section:not(.hero){padding:32px 26px}
}

@media (max-width:960px){
  body{padding-left:0}
  .rail{
    position:sticky;top:0;width:100%;height:auto;bottom:auto;
    flex-direction:row;align-items:center;gap:12px;
    padding:10px 16px;
    border-right:0;border-bottom:1px solid var(--line);
    background:rgba(17,16,20,.92);
  }
  .brand{width:40px;height:40px;border-radius:14px}
  .rail nav{flex:1 1 auto;overflow-x:auto;scrollbar-width:none;-ms-overflow-style:none}
  .rail nav::-webkit-scrollbar{display:none}
  .rail nav p{flex-direction:row;gap:4px}
  .rail nav a{
    white-space:nowrap;border-left:0;border-bottom:2px solid transparent;
    border-radius:10px;padding:6px 10px;
  }
  .rail nav a:hover,.rail nav a:focus-visible{transform:none;border-bottom-color:var(--red)}
  .cta{flex:0 0 auto;padding:10px 14px;min-height:42px;font-size:.88rem;box-shadow:none}
  main{grid-template-columns:minmax(0,1fr);padding:0 20px 16px;column-gap:0}
  main > *:not(aside){grid-column:1}
  main > aside{grid-column:1;grid-row:auto;position:static;margin:0 0 24px}
  aside.toc{padding:16px 14px}
  aside.toc p{flex-direction:row;flex-wrap:wrap;gap:6px}
  aside.toc a{min-height:40px;padding:4px 10px;background:rgba(243,239,233,.05);font-size:.95rem}
  main > section.hero{grid-column:1;min-height:0;padding:44px 0 36px;gap:22px}
  main > section:not(.hero){padding:28px 20px;scroll-margin-top:84px;border-radius:24px}
  footer{grid-template-columns:1fr;padding:30px 20px 40px;margin-top:34px}
}

@media (max-width:620px){
  main > section.hero{flex-direction:column-reverse;align-items:flex-end;padding:36px 0 30px}
  .hero-art{width:132px;aspect-ratio:4 / 3}
  h1{font-size:clamp(2.1rem,9vw,2.9rem)}
  .hero-lede{font-size:1rem}
  .layer.l-grid{background-size:20px 20px}
  main > section:not(.hero){padding:24px 18px}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .rv{opacity:1;transform:none;transition:none}
  .layer{will-change:auto}
  .brand,.cta,.rail nav a{transition:none}
}

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