:root{
  --bg:#F7F5FB;
  --surface:#FFFFFF;
  --surface-2:#F1EEF9;
  --glass:rgba(255,255,255,.72);
  --glass-border:rgba(255,255,255,.55);
  --text:#17202A;
  --text-2:#334155;
  --text-3:#5B6472;
  --heading:#1F2937;
  --brand:#7C3AED;
  --brand-deep:#5B21B6;
  --brand-soft:#EDE9FE;
  --accent:#2563EB;
  --accent-soft:#DBEAFE;
  --border:#E2DCF0;
  --link:#5B21B6;
  --footer-bg:#241B3A;
  --footer-text:#E5E7EB;
  --footer-muted:#C7BFDD;
  --banner-overlay:rgba(23,32,42,.62);
  --shadow:0 6px 24px rgba(36,27,58,.08);
  --shadow-hover:0 16px 40px rgba(36,27,58,.16);
  --radius:16px;
  --radius-sm:12px;
  --radius-lg:22px;
  --ease:cubic-bezier(.22,.61,.36,1);
}
html[data-theme="dark"]{
  --bg:#12101A;
  --surface:#1B1826;
  --surface-2:#221E30;
  --glass:rgba(34,30,48,.68);
  --glass-border:rgba(255,255,255,.12);
  --text:#E5E7EB;
  --text-2:#E2E8F0;
  --text-3:#B7BECB;
  --heading:#FFFFFF;
  --brand:#A78BFA;
  --brand-deep:#C4B5FD;
  --brand-soft:#2A2340;
  --accent:#60A5FA;
  --accent-soft:#1E293B;
  --border:#332C48;
  --link:#C4B5FD;
  --footer-bg:#0D0B14;
  --footer-text:#F1F5F9;
  --footer-muted:#B7BECB;
  --banner-overlay:rgba(0,0,0,.66);
  --shadow:0 6px 24px rgba(0,0,0,.45);
  --shadow-hover:0 16px 40px rgba(0,0,0,.6);
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  font-family:"PingFang SC","Microsoft YaHei","Hiragino Sans GB","Source Han Sans SC",system-ui,-apple-system,sans-serif;
  background:var(--bg);
  color:var(--text);
  line-height:1.85;
  font-size:16px;
  transition:background .35s ease,color .35s ease;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
  overflow-x:hidden;
}
img,svg{max-width:100%;display:block}
a{color:var(--link);text-decoration:none;transition:color .22s ease}
a:hover{text-decoration:underline}
h1,h2,h3,h4{color:var(--heading);line-height:1.35;font-weight:700;letter-spacing:.2px}
h1{font-size:2rem}
h2{font-size:1.6rem;margin-bottom:1rem}
h3{font-size:1.2rem;margin-bottom:.6rem}
h4{font-size:1.05rem;margin-bottom:.4rem;color:var(--text-2)}
p{color:var(--text);margin-bottom:1rem}
ul,ol{color:var(--text-2)}
li{margin-bottom:.35rem}
::selection{background:var(--brand);color:#FFFFFF}
.wrap{max-width:1180px;margin:0 auto;padding:0 20px}
section{padding:56px 0;position:relative}
.sec-head{text-align:center;margin-bottom:32px}
.sec-head h2{position:relative;display:inline-block;padding-bottom:12px}
.sec-head h2::after{
  content:"";
  position:absolute;
  left:50%;
  bottom:0;
  transform:translateX(-50%);
  width:56px;
  height:4px;
  border-radius:999px;
  background:linear-gradient(90deg,var(--brand),var(--accent));
}
.sec-head p{color:var(--text-3);max-width:760px;margin:14px auto 0}
.card{
  background:var(--surface);
  border:1px solid var(--border);
  border-radius:var(--radius);
  padding:24px;
  box-shadow:var(--shadow);
  transition:transform .3s var(--ease),box-shadow .3s var(--ease),border-color .3s ease,background .35s ease;
  position:relative;
  overflow:hidden;
}
.card::before{
  content:"";
  position:absolute;
  inset:0 0 auto 0;
  height:3px;
  background:linear-gradient(90deg,var(--brand),var(--accent));
  opacity:0;
  transition:opacity .3s ease;
}
.card:hover{transform:translateY(-6px);box-shadow:var(--shadow-hover);border-color:var(--brand)}
.card:hover::before{opacity:1}
.grid{display:grid;gap:20px}
.grid-2{grid-template-columns:repeat(2,1fr)}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-4{grid-template-columns:repeat(4,1fr)}
.btn{
  display:inline-block;
  padding:12px 28px;
  border-radius:999px;
  background:linear-gradient(120deg,var(--brand),var(--accent));
  background-size:180% 180%;
  color:#FFFFFF;
  font-weight:600;
  border:none;
  cursor:pointer;
  box-shadow:0 8px 20px rgba(124,58,237,.28);
  transition:transform .25s var(--ease),box-shadow .25s ease,background-position .5s ease;
}
.btn:hover{
  background-position:100% 0;
  transform:translateY(-3px);
  box-shadow:0 14px 30px rgba(124,58,237,.38);
  text-decoration:none;
  color:#FFFFFF;
}
.btn:active{transform:translateY(-1px)}
.btn-ghost{
  background:transparent;
  color:var(--brand-deep);
  border:2px solid var(--brand);
  box-shadow:none;
}
.btn-ghost:hover{background:var(--brand-soft);color:var(--brand-deep);box-shadow:none}
.tag{
  display:inline-block;
  padding:4px 14px;
  border-radius:999px;
  background:var(--brand-soft);
  color:var(--brand-deep);
  font-size:.82rem;
  font-weight:600;
  margin:0 6px 6px 0;
  letter-spacing:.3px;
}
.skip{position:absolute;left:-9999px}
.skip:focus{left:20px;top:20px;background:var(--surface);padding:10px 16px;border-radius:8px;z-index:999;color:var(--text)}
/* header */
.site-header{
  position:sticky;
  top:0;
  z-index:100;
  background:var(--glass);
  -webkit-backdrop-filter:blur(16px) saturate(180%);
  backdrop-filter:blur(16px) saturate(180%);
  border-bottom:1px solid var(--glass-border);
  transition:background .35s ease,border-color .35s ease;
}
.nav{display:flex;align-items:center;justify-content:space-between;height:68px;gap:16px}
.logo{display:flex;align-items:center;gap:10px;font-size:1.22rem;font-weight:800;color:var(--heading);white-space:nowrap}
.logo svg{width:36px;height:36px;flex:0 0 auto;border-radius:12px;transition:transform .35s var(--ease)}
.logo:hover{text-decoration:none}
.logo:hover svg{transform:rotate(-8deg) scale(1.06)}
.nav-links{display:flex;gap:20px;list-style:none;align-items:center;flex-wrap:wrap}
.nav-links li{margin:0}
.nav-links a{color:var(--text-2);font-weight:600;font-size:.95rem;position:relative;padding-bottom:4px}
.nav-links a::after{
  content:"";
  position:absolute;
  left:0;
  bottom:0;
  width:0;
  height:2px;
  border-radius:999px;
  background:linear-gradient(90deg,var(--brand),var(--accent));
  transition:width .28s var(--ease);
}
.nav-links a:hover{color:var(--brand-deep);text-decoration:none}
.nav-links a:hover::after{width:100%}
.nav-tools{display:flex;align-items:center;gap:10px}
.search-box{
  display:flex;
  align-items:center;
  background:var(--surface-2);
  border:1px solid var(--border);
  border-radius:999px;
  padding:4px 6px 4px 14px;
  transition:border-color .25s ease,box-shadow .25s ease,background .35s ease;
}
.search-box:focus-within{border-color:var(--brand);box-shadow:0 0 0 3px var(--brand-soft)}
.search-box input{border:none;background:transparent;outline:none;color:var(--text);width:130px;font-size:.9rem;font-family:inherit}
.search-box input::placeholder{color:var(--text-3)}
.icon-btn{
  background:var(--surface-2);
  border:1px solid var(--border);
  border-radius:50%;
  width:40px;
  height:40px;
  display:flex;
  align-items:center;
  justify-content:center;
  cursor:pointer;
  color:var(--text-2);
  flex:0 0 auto;
  transition:background .25s ease,color .25s ease,transform .25s var(--ease),border-color .25s ease;
}
.icon-btn:hover{background:var(--brand-soft);color:var(--brand-deep);border-color:var(--brand);transform:translateY(-2px)}
.icon-btn:active{transform:translateY(0)}
.menu-toggle{display:none}
/* breadcrumb */
.crumb{font-size:.86rem;color:var(--text-3);padding:16px 0 0}
.crumb a{color:var(--text-2)}
.crumb a:hover{color:var(--brand-deep)}
/* banner */
.banner{
  position:relative;
  border-radius:var(--radius-lg);
  overflow:hidden;
  background:linear-gradient(120deg,#4C1D95,#7C3AED 55%,#2563EB);
  box-shadow:var(--shadow-hover);
}
.banner::before{
  content:"";
  position:absolute;
  inset:-40%;
  background:
    radial-gradient(circle at 20% 30%,rgba(255,255,255,.22),transparent 45%),
    radial-gradient(circle at 80% 70%,rgba(37,99,235,.35),transparent 50%);
  animation:bgFloat 14s ease-in-out infinite alternate;
  z-index:0;
}
@keyframes bgFloat{
  0%{transform:translate3d(0,0,0) scale(1)}
  100%{transform:translate3d(3%,-3%,0) scale(1.08)}
}
.slide{display:none;padding:64px 40px;min-height:340px;position:relative;z-index:1}
.slide.active{display:block;animation:slideIn .7s var(--ease) both}
@keyframes slideIn{
  from{opacity:0;transform:translateY(18px)}
  to{opacity:1;transform:none}
}
.slide::after{content:"";position:absolute;inset:0;background:var(--banner-overlay);z-index:1}
.slide-inner{position:relative;z-index:2;max-width:720px}
.slide h2{color:#FFFFFF;font-size:1.9rem;text-shadow:0 2px 12px rgba(0,0,0,.5)}
.slide p{color:#F1F5F9;text-shadow:0 1px 8px rgba(0,0,0,.5)}
.slide .tag{background:rgba(255,255,255,.92);color:#4C1D95}
.dots{position:absolute;bottom:16px;left:40px;z-index:3;display:flex;gap:8px}
.dots span{width:10px;height:10px;border-radius:50%;background:rgba(255,255,255,.5);cursor:pointer;transition:width .3s var(--ease),background .3s ease}
.dots span:hover{background:rgba(255,255,255,.8)}
.dots span.active{background:#FFFFFF;width:26px;border-radius:6px}
/* stats */
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;text-align:center}
.stat-num{
  font-size:2rem;
  font-weight:800;
  background:linear-gradient(120deg,var(--brand),var(--accent));
  -webkit-background-clip:text;
  background-clip:text;
  color:transparent;
  line-height:1.3;
}
.stat-label{color:var(--text-2);font-size:.95rem}
/* articles */
.article-card h3 a{color:var(--heading);transition:color .22s ease}
.article-card h3 a:hover{color:var(--brand-deep);text-decoration:none}
.article-meta{font-size:.82rem;color:var(--text-3);margin-bottom:8px;letter-spacing:.2px}
.article-card p{color:var(--text-2);font-size:.95rem}
.readmore{font-weight:600;color:var(--brand-deep);display:inline-flex;align-items:center;gap:6px}
.readmore::after{content:"→";transition:transform .25s var(--ease)}
.readmore:hover{text-decoration:none}
.readmore:hover::after{transform:translateX(5px)}
/* faq */
.faq-item{
  border:1px solid var(--border);
  border-radius:var(--radius-sm);
  margin-bottom:12px;
  background:var(--glass);
  -webkit-backdrop-filter:blur(12px);
  backdrop-filter:blur(12px);
  overflow:hidden;
  transition:border-color .28s ease,box-shadow .28s ease,background .35s ease;
}
.faq-item:hover{border-color:var(--brand)}
.faq-item.open{border-color:var(--brand);box-shadow:var(--shadow)}
.faq-q{
  width:100%;
  text-align:left;
  padding:18px 22px;
  background:transparent;
  border:none;
  font-size:1.02rem;
  font-weight:700;
  color:var(--heading);
  cursor:pointer;
  display:flex;
  justify-content:space-between;
  gap:12px;
  align-items:center;
  font-family:inherit;
  transition:background .25s ease;
}
.faq-q:hover{background:var(--surface-2)}
.faq-q .arrow{color:var(--brand-deep);transition:transform .3s var(--ease);flex:0 0 auto}
.faq-item.open .faq-q .arrow{transform:rotate(180deg)}
.faq-a{max-height:0;overflow:hidden;transition:max-height .35s var(--ease),padding .35s ease;padding:0 22px}
.faq-item.open .faq-a{max-height:520px;padding:0 22px 20px}
.faq-a p{color:var(--text-2);margin:0}
/* table */
table{width:100%;border-collapse:collapse;margin:16px 0;border-radius:var(--radius-sm);overflow:hidden;box-shadow:var(--shadow);background:var(--surface)}
th,td{border:1px solid var(--border);padding:12px 14px;text-align:left;font-size:.94rem}
th{background:var(--surface-2);color:var(--heading);font-weight:700}
td{color:var(--text-2)}
tbody tr{transition:background .22s ease}
tbody tr:hover{background:var(--surface-2)}
/* footer */
.site-footer{
  background:var(--footer-bg);
  color:var(--footer-text);
  padding:56px 0 24px;
  margin-top:40px;
  position:relative;
  overflow:hidden;
}
.site-footer::before{
  content:"";
  position:absolute;
  top:0;
  left:0;
  right:0;
  height:3px;
  background:linear-gradient(90deg,var(--brand),var(--accent),var(--brand));
  background-size:200% 100%;
  animation:lineFlow 6s linear infinite;
}
@keyframes lineFlow{
  0%{background-position:0 0}
  100%{background-position:200% 0}
}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:28px}
.site-footer h4{color:#FFFFFF;font-size:1rem;margin-bottom:14px}
.site-footer p,.site-footer li,.site-footer a{color:var(--footer-muted);font-size:.9rem}
.site-footer a{transition:color .22s ease,padding-left .22s ease}
.site-footer a:hover{color:#FFFFFF;text-decoration:none;padding-left:4px}
.site-footer ul{list-style:none}
.site-footer li{margin-bottom:8px}
.footer-bottom{border-top:1px solid rgba(255,255,255,.16);margin-top:32px;padding-top:20px;text-align:center;font-size:.84rem;color:var(--footer-muted)}
.footer-bottom p{margin-bottom:.4rem;color:var(--footer-muted)}
/* back to top */
.to-top{
  position:fixed;
  right:24px;
  bottom:24px;
  width:46px;
  height:46px;
  border-radius:50%;
  background:linear-gradient(120deg,var(--brand),var(--accent));
  color:#FFFFFF;
  border:none;
  cursor:pointer;
  display:none;
  align-items:center;
  justify-content:center;
  box-shadow:var(--shadow-hover);
  z-index:120;
  transition:transform .25s var(--ease),opacity .3s ease;
}
.to-top.show{display:flex;animation:popIn .35s var(--ease) both}
.to-top:hover{transform:translateY(-4px) scale(1.06)}
@keyframes popIn{
  from{opacity:0;transform:translateY(14px) scale(.85)}
  to{opacity:1;transform:none}
}
/* reveal */
.reveal{opacity:0;transform:translateY(24px);transition:opacity .7s var(--ease),transform .7s var(--ease)}
.reveal.visible{opacity:1;transform:none}
/* focus */
a:focus-visible,button:focus-visible,input:focus-visible{outline:2px solid var(--brand);outline-offset:2px}
/* responsive */
@media (max-width:1024px){
  .nav-links{gap:14px}
  .nav-links a{font-size:.9rem}
  .search-box input{width:100px}
}
@media (max-width:960px){
  .grid-3,.grid-4{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:1fr 1fr}
  .nav-links{
    display:none;
    position:absolute;
    top:68px;
    left:0;
    right:0;
    background:var(--glass);
    -webkit-backdrop-filter:blur(18px) saturate(180%);
    backdrop-filter:blur(18px) saturate(180%);
    flex-direction:column;
    align-items:flex-start;
    padding:16px 20px;
    border-bottom:1px solid var(--border);
    box-shadow:var(--shadow);
    gap:4px;
    animation:menuDrop .3s var(--ease) both;
  }
  @keyframes menuDrop{
    from{opacity:0;transform:translateY(-10px)}
    to{opacity:1;transform:none}
  }
  .nav-links.open{display:flex}
  .nav-links li{width:100%}
  .nav-links a{display:block;padding:10px 4px;width:100%}
  .menu-toggle{display:flex}
}
@media (max-width:640px){
  body{font-size:15px}
  .grid-2,.grid-3,.grid-4{grid-template-columns:1fr}
  .stats{grid-template-columns:1fr 1fr}
  .footer-grid{grid-template-columns:1fr}
  h1{font-size:1.6rem}
  h2{font-size:1.35rem}
  section{padding:40px 0}
  .slide{padding:44px 22px;min-height:300px}
  .slide h2{font-size:1.5rem}
  .dots{left:22px}
  .search-box{display:none}
  .card{padding:20px}
  .to-top{right:16px;bottom:16px;width:42px;height:42px}
  .crumb{padding:12px 0 0}
}
@media (max-width:400px){
  .stats{grid-template-columns:1fr}
  .wrap{padding:0 14px}
}
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.001ms !important;animation-iteration-count:1 !important;transition-duration:.001ms !important;scroll-behavior:auto !important}
}
@media print{
  .site-header,.to-top,.site-footer::before{display:none}
  body{background:#FFFFFF;color:#000000}
  .card{box-shadow:none;border:1px solid #CCCCCC}
}