@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:#1c1726;
  --p1:#6514ff;
  --p2:#bf00ff;
  --paper:#f7f3ff;
  --white:#ffffff;
  --line:rgba(28,23,38,.16);
  --dim:rgba(28,23,38,.7);
  --soft:rgba(255,255,255,.72);
}

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

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

body{
  margin:0;
  overflow-x:hidden;
  font-family:"Inter","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  font-size:17px;
  line-height:1.75;
  color:var(--ink);
  background:var(--paper);
}

img{max-width:100%;height:auto;display:block}
a{color:inherit;text-decoration:none}
h1,h2,h3{font-weight:800;letter-spacing:-.028em;line-height:1.08;margin:0}
p{margin:0 0 1em}

/* ---------- 左侧固定导轨 ---------- */

.rail{
  position:fixed;
  inset:0 auto 0 0;
  width:268px;
  z-index:40;
  display:flex;
  flex-direction:column;
  gap:20px;
  padding:30px 22px;
  overflow-y:auto;
  background:var(--ink);
  color:var(--white);
  border-right:6px solid var(--p1);
}

.brand{
  display:flex;
  align-items:center;
  min-height:44px;
  font-size:24px;
  font-weight:800;
  letter-spacing:-.04em;
  line-height:1.1;
}

.brand:hover{color:var(--p2)}

.brand-tag{
  margin:-10px 0 0;
  font-size:16px;
  line-height:1.4;
  color:var(--soft);
  letter-spacing:.06em;
}

.rail-nav{margin-top:4px}

.rail-list{
  counter-reset:rail;
  list-style:none;
  margin:0;
  padding:0;
  display:flex;
  flex-direction:column;
}

.rail-list li{counter-increment:rail}

.rail-list a{
  display:flex;
  align-items:baseline;
  gap:10px;
  min-height:44px;
  padding:11px 4px;
  font-size:16px;
  font-weight:600;
  line-height:1.4;
  border-bottom:1px solid rgba(255,255,255,.14);
  transition:color .2s ease,transform .2s ease,border-color .2s ease;
}

.rail-list a::before{
  content:counter(rail,decimal-leading-zero);
  font-family:"JetBrains Mono",ui-monospace,monospace;
  font-size:13px;
  color:var(--p2);
  flex:none;
}

.rail-list a:hover,
.rail-list a:focus-visible{
  color:var(--p2);
  transform:translateX(6px);
  border-color:var(--p2);
}

.rail-cta{
  margin-top:auto;
  display:flex;
  align-items:center;
  justify-content:center;
  min-height:48px;
  padding:14px 12px;
  font-size:16px;
  font-weight:800;
  text-align:center;
  color:var(--white);
  background:var(--p1);
  border-bottom:5px solid var(--p2);
  transition:background .22s ease,color .22s ease;
}

.rail-cta:hover{background:var(--p2);color:var(--ink)}

/* ---------- 开屏 ---------- */

.hero{
  position:relative;
  min-height:70vh;
  display:flex;
  align-items:flex-end;
  justify-content:flex-end;
  overflow:hidden;
  padding:110px clamp(20px,5vw,76px) 72px;
  text-align:right;
  color:var(--white);
  background:var(--ink);
}

.hero::before{
  content:"";
  position:absolute;
  inset:-25%;
  background:repeating-linear-gradient(45deg,rgba(101,20,255,.28) 0 28px,transparent 28px 56px);
  animation:stripe 16s linear infinite;
}

.hero-shapes span{
  position:absolute;
  display:block;
  opacity:.6;
  mix-blend-mode:screen;
  animation:drift 12s ease-in-out infinite alternate;
}

.hero-shapes span:nth-child(1){
  width:56vw;height:56vw;max-width:600px;max-height:600px;
  left:-10vw;top:-12vw;
  background:linear-gradient(135deg,var(--p1),rgba(101,20,255,0) 72%);
}

.hero-shapes span:nth-child(2){
  width:34vw;height:34vw;max-width:360px;max-height:360px;
  left:22vw;bottom:-14vw;
  background:linear-gradient(210deg,var(--p2),rgba(191,0,255,0) 70%);
  animation-delay:-4s;
}

.hero-shapes span:nth-child(3){
  width:18vw;height:18vw;max-width:200px;max-height:200px;
  right:8vw;top:12vh;
  background:linear-gradient(45deg,rgba(191,0,255,.85),rgba(101,20,255,0) 78%);
  animation-delay:-7s;
}

.hero-inner{
  position:relative;
  z-index:2;
  max-width:820px;
  margin-left:auto;
}

.eyebrow{
  margin:0 0 14px;
  font-size:16px;
  font-weight:700;
  letter-spacing:.22em;
  color:var(--p2);
}

.hero h1{
  font-size:clamp(2.4rem,7.4vw,5.1rem);
  line-height:.98;
  letter-spacing:-.045em;
  text-shadow:0 0 0 transparent;
}

.hero-lead{
  margin:22px 0 26px auto;
  max-width:44ch;
  font-size:17px;
  line-height:1.8;
  color:rgba(255,255,255,.82);
}

.hero-actions{
  display:flex;
  flex-wrap:wrap;
  gap:12px;
  justify-content:flex-end;
}

.hero-badges{
  position:absolute;
  inset:0;
  z-index:3;
  pointer-events:none;
}

.badge{
  position:absolute;
  padding:8px 14px;
  font-size:16px;
  font-weight:800;
  letter-spacing:.02em;
  color:var(--white);
  background:var(--p1);
  box-shadow:5px 5px 0 rgba(0,0,0,.35);
  animation:float 6s ease-in-out infinite alternate;
}

.badge-a{left:6%;top:22%;transform:rotate(-7deg)}
.badge-b{left:18%;bottom:26%;background:var(--p2);animation-delay:-2s;transform:rotate(4deg)}
.badge-c{right:8%;top:64%;background:var(--ink);border:2px solid var(--p2);animation-delay:-4s}

/* ---------- 按钮 ---------- */

.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  min-height:48px;
  padding:14px 24px;
  font-size:16px;
  font-weight:800;
  letter-spacing:.01em;
  border:2px solid transparent;
  transition:background .22s ease,color .22s ease,transform .22s ease;
}

.btn-solid{background:var(--p1);color:var(--white);border-bottom:4px solid var(--p2)}
.btn-solid:hover{background:var(--p2);color:var(--ink);transform:translateY(-2px)}
.btn-line{border-color:rgba(255,255,255,.55);color:var(--white)}
.btn-line:hover{border-color:var(--p2);color:var(--p2);transform:translateY(-2px)}

/* ---------- 主区域 ---------- */

main{
  max-width:1160px;
  margin:0 auto;
  padding:0 clamp(18px,4vw,56px);
}

.intro{
  display:grid;
  gap:34px;
  padding:clamp(48px,7vw,88px) 0 clamp(28px,4vw,44px);
}

.intro-head h2{
  font-size:clamp(1.75rem,3.6vw,2.7rem);
  max-width:24ch;
}

.subtitle{
  margin:12px 0 0;
  max-width:56ch;
  font-size:17px;
  line-height:1.8;
  color:var(--dim);
}

.pull{
  margin:0;
  padding:26px 28px;
  background:var(--white);
  border-left:10px solid var(--p1);
  border-bottom:4px solid var(--p2);
}

.pull blockquote{
  margin:0 0 12px;
  font-family:"Playfair Display","Songti SC",serif;
  font-style:italic;
  font-size:clamp(1.15rem,2.3vw,1.5rem);
  line-height:1.6;
  letter-spacing:-.01em;
}

.pull figcaption{
  font-size:16px;
  color:var(--dim);
  letter-spacing:.04em;
}

.body-grid{
  display:grid;
  grid-template-columns:264px minmax(0,1fr);
  gap:clamp(24px,4vw,52px);
  padding:clamp(24px,4vw,44px) 0 clamp(48px,6vw,76px);
  align-items:start;
}

/* ---------- 侧栏 ---------- */

.side{
  position:sticky;
  top:26px;
  padding:20px;
  background:var(--white);
  border-top:8px solid var(--ink);
  border-bottom:4px solid var(--p2);
}

.side-title{
  font-size:18px;
  letter-spacing:-.01em;
  margin-bottom:12px;
}

.side-list{
  counter-reset:side;
  list-style:none;
  margin:0 0 14px;
  padding:0;
}

.side-list li{counter-increment:side}

.side-list a{
  display:flex;
  gap:8px;
  align-items:baseline;
  min-height:40px;
  padding:9px 0;
  font-size:16px;
  font-weight:600;
  border-bottom:1px dashed var(--line);
  transition:color .2s ease,padding-left .2s ease;
}

.side-list a::before{
  content:counter(side,decimal-leading-zero);
  font-family:"JetBrains Mono",ui-monospace,monospace;
  font-size:13px;
  color:var(--p1);
}

.side-list a:hover{color:var(--p1);padding-left:6px}

.side-note{
  margin:0;
  padding-top:12px;
  font-size:16px;
  line-height:1.7;
  color:var(--dim);
  border-top:2px solid var(--line);
}

/* ---------- 正文 ---------- */

.content{min-width:0}

.content > article{
  scroll-margin-top:24px;
  padding:0 0 clamp(34px,5vw,54px);
  margin-bottom:clamp(34px,5vw,54px);
  border-bottom:2px dashed var(--line);
}

.content > article:last-child{border-bottom:0;margin-bottom:0}

.content h2{
  font-size:clamp(1.55rem,2.9vw,2.15rem);
  margin-bottom:.55em;
}

.content h3{
  font-size:1.2rem;
  margin:1.5em 0 .5em;
  padding-bottom:.3em;
  border-bottom:3px solid var(--p2);
  display:inline-block;
}

.content p{max-width:70ch;color:rgba(28,23,38,.88)}
.content ul,.content ol{padding-left:1.35em;max-width:66ch}
.content li{margin-bottom:.55em}
.content li::marker{color:var(--p1);font-weight:700}
.content a{color:var(--p1);border-bottom:2px solid rgba(101,20,255,.3)}
.content a:hover{border-color:var(--p2);color:var(--p2)}

.content blockquote{
  margin:1.6em 0;
  padding:.5em 0 .5em 1.15em;
  border-left:8px solid var(--p2);
  color:var(--dim);
  max-width:66ch;
}

.content strong{font-weight:800}
.content code{
  font-family:"JetBrains Mono",ui-monospace,monospace;
  font-size:.95em;
  padding:2px 6px;
  background:rgba(101,20,255,.1);
}

.content table{
  width:100%;
  border-collapse:collapse;
  margin:1.4em 0;
  font-size:16px;
}

.content th,.content td{
  padding:10px 12px;
  text-align:left;
  border-bottom:1px solid var(--line);
}

.content th{background:var(--ink);color:var(--white);font-weight:700}

.content figure{margin:1.6em 0}
.content figcaption{font-size:16px;color:var(--dim);margin-top:8px}

/* ---------- 收尾 ---------- */

.outro{
  padding:clamp(40px,6vw,72px) clamp(24px,5vw,56px);
  background:linear-gradient(125deg,var(--p1),var(--p2));
  color:var(--white);
  text-align:right;
}

.outro h2{font-size:clamp(1.7rem,3.6vw,2.6rem);max-width:26ch;margin-left:auto}
.outro .subtitle{color:rgba(255,255,255,.9);margin-left:auto}
.outro p{max-width:58ch;margin-left:auto;color:rgba(255,255,255,.92)}
.outro .btn-solid{margin-top:14px;background:var(--ink);color:var(--white);border-bottom-color:var(--white)}
.outro .btn-solid:hover{background:var(--white);color:var(--ink)}

/* ---------- 页脚 ---------- */

footer{
  margin-top:clamp(48px,7vw,88px);
  background:var(--ink);
  color:var(--white);
}

.foot-cta{
  padding:clamp(36px,6vw,64px) clamp(20px,5vw,60px);
  text-align:right;
  background:repeating-linear-gradient(135deg,rgba(191,0,255,.35) 0 22px,rgba(28,23,38,0) 22px 44px);
  border-bottom:6px solid var(--p1);
}

.foot-cta h2{font-size:clamp(1.6rem,3.4vw,2.4rem);max-width:24ch;margin-left:auto}
.foot-cta .subtitle{color:rgba(255,255,255,.8);margin-left:auto}

.foot-cols{
  display:grid;
  grid-template-columns:repeat(3,minmax(0,1fr));
  gap:clamp(20px,4vw,48px);
  padding:clamp(32px,5vw,56px) clamp(20px,5vw,60px);
}

.foot-cols dl{margin:0}

.foot-cols dt{
  font-size:16px;
  font-weight:800;
  letter-spacing:.16em;
  color:var(--p2);
  padding-bottom:10px;
  margin-bottom:10px;
  border-bottom:2px solid rgba(255,255,255,.16);
}

.foot-cols dd{
  margin:0 0 8px;
  font-size:16px;
  line-height:1.7;
  color:rgba(255,255,255,.75);
}

.foot-cols dd a{
  display:block;
  min-height:40px;
  padding:8px 0;
  color:var(--white);
  transition:color .2s ease,transform .2s ease;
}

.foot-cols dd a:hover{color:var(--p2);transform:translateX(5px)}

.copy{
  margin:0;
  padding:18px clamp(20px,5vw,60px) 26px;
  font-size:16px;
  color:rgba(255,255,255,.6);
  border-top:1px solid rgba(255,255,255,.14);
}

/* ---------- 动效 ---------- */

.reveal [data-reveal]{
  opacity:0;
  transform:translateY(26px);
  transition:opacity .5s ease,transform .5s ease;
  transition-delay:var(--d,0ms);
}

.reveal [data-reveal].is-in{
  opacity:1;
  transform:none;
}

@keyframes stripe{
  from{transform:translate3d(0,0,0)}
  to{transform:translate3d(56px,56px,0)}
}

@keyframes drift{
  from{transform:translate3d(0,0,0) scale(1)}
  to{transform:translate3d(2vw,3vh,0) scale(1.08)}
}

@keyframes float{
  from{transform:translateY(0) rotate(-6deg)}
  to{transform:translateY(-14px) rotate(-2deg)}
}

/* ---------- 桌面 ---------- */

@media (min-width:900px){
  body{padding-left:268px}
}

/* ---------- 窄屏 ---------- */

@media (max-width:899px){
  body{font-size:17px}

  .rail{
    position:sticky;
    inset:0;
    width:auto;
    flex-direction:row;
    align-items:center;
    gap:12px;
    padding:8px 14px;
    overflow-x:auto;
    overflow-y:hidden;
    border-right:0;
    border-bottom:5px solid var(--p1);
  }

  .brand{font-size:18px;min-height:44px;white-space:nowrap}
  .brand-tag{display:none}

  .rail-nav{margin:0;flex:1 1 auto;min-width:0}

  .rail-list{
    flex-direction:row;
    gap:2px;
    overflow-x:auto;
    scrollbar-width:none;
  }

  .rail-list::-webkit-scrollbar{display:none}

  .rail-list a{
    border-bottom:0;
    padding:12px 10px;
    min-height:44px;
    white-space:nowrap;
    font-size:16px;
  }

  .rail-list a:hover{transform:none}

  .rail-cta{margin-top:0;min-height:44px;padding:10px 14px;white-space:nowrap;border-bottom-width:4px}

  .hero{min-height:62vh;padding:70px 20px 56px}
  .hero-lead{margin-left:auto}
  .hero-actions{justify-content:flex-end}

  .badge{padding:7px 12px;font-size:16px}
  .badge-a{left:4%;top:12%}
  .badge-b{display:none}
  .badge-c{right:6%;top:auto;bottom:8%}

  .content > article{scroll-margin-top:82px}

  .body-grid{grid-template-columns:minmax(0,1fr)}

  .side{position:static}

  .foot-cols{grid-template-columns:minmax(0,1fr)}
  .foot-cta{text-align:left}
  .foot-cta h2,.foot-cta .subtitle{margin-left:0}
}

@media (max-width:520px){
  .hero h1{font-size:clamp(2rem,10vw,2.9rem)}
  .outro{text-align:left}
  .outro h2,.outro .subtitle,.outro p{margin-left:0}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .hero::before,
  .hero-shapes span,
  .badge{animation:none}
  .reveal [data-reveal]{opacity:1;transform:none;transition:none}
}

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