:root{
  --brand:#1B4F9C;
  --brand-dark:#123A75;
  --brand-light:#2E6BC4;
  --brand-glow:rgba(27,79,156,.35);
  --accent:#F59E0B;
  --accent-soft:rgba(245,158,11,.14);
  --text-main:#17202A;
  --text-body:#1F2937;
  --text-sub:#334155;
  --text-muted:#4B5563;
  --bg-page:#FFFFFF;
  --bg-soft:#F4F7FB;
  --bg-card:#FFFFFF;
  --glass:rgba(255,255,255,.72);
  --glass-border:rgba(255,255,255,.55);
  --border:#D6DEE8;
  --link:#14498C;
  --link-hover:#0B2E5C;
  --btn-text:#FFFFFF;
  --footer-bg:#12233D;
  --footer-text:#E2E8F0;
  --footer-sub:#B7C4D6;
  --shadow:0 4px 18px rgba(18,58,117,.10);
  --shadow-lg:0 14px 40px rgba(18,58,117,.16);
  --radius:16px;
  --radius-sm:10px;
  --radius-pill:999px;
}
html[data-theme="dark"]{
  --brand:#5B9BEA;
  --brand-dark:#3D7FD1;
  --brand-light:#7FB4F2;
  --brand-glow:rgba(91,155,234,.35);
  --accent:#FBBF24;
  --accent-soft:rgba(251,191,36,.16);
  --text-main:#FFFFFF;
  --text-body:#E5E7EB;
  --text-sub:#CBD5E1;
  --text-muted:#A9B6C7;
  --bg-page:#0E1622;
  --bg-soft:#16202E;
  --bg-card:#182432;
  --glass:rgba(24,36,50,.68);
  --glass-border:rgba(255,255,255,.10);
  --border:#2C3B4E;
  --link:#8CBEF5;
  --link-hover:#B6D6FA;
  --btn-text:#0E1622;
  --footer-bg:#0A1019;
  --footer-text:#E2E8F0;
  --footer-sub:#A9B6C7;
  --shadow:0 4px 18px rgba(0,0,0,.45);
  --shadow-lg:0 14px 40px rgba(0,0,0,.55);
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  font-family:"PingFang SC","Microsoft YaHei","Hiragino Sans GB","Source Han Sans SC",sans-serif;
  background:var(--bg-page);
  color:var(--text-body);
  line-height:1.85;
  font-size:16px;
  overflow-x:hidden;
  transition:background-color .35s ease,color .35s ease;
}
h1,h2,h3,h4{color:var(--text-main);line-height:1.4;font-weight:700}
h1{font-size:2rem;letter-spacing:.2px}
h2{font-size:1.55rem;margin-bottom:.6em;position:relative;padding-bottom:.35em}
h2::after{
  content:"";
  position:absolute;left:0;bottom:0;
  width:56px;height:4px;border-radius:4px;
  background:linear-gradient(90deg,var(--brand),var(--brand-light),var(--accent));
}
h3{font-size:1.22rem;margin-bottom:.5em;margin-top:1.2em}
h4{font-size:1.05rem;color:var(--text-sub)}
p{color:var(--text-body);margin-bottom:1em}
a{color:var(--link);text-decoration:none;transition:color .2s ease}
a:hover,a:focus{color:var(--link-hover);text-decoration:underline}
ul,ol{margin:0 0 1em 1.4em}
li{color:var(--text-body);margin-bottom:.4em}
img,svg{max-width:100%;display:block}
strong{color:var(--text-main)}
.container{width:100%;max-width:1180px;margin:0 auto;padding:0 18px}
section{padding:56px 0}
.section-soft{background:var(--bg-soft)}
.skip-link{position:absolute;left:-9999px}
.skip-link:focus{left:12px;top:12px;background:var(--brand);color:var(--btn-text);padding:8px 14px;border-radius:var(--radius-sm);z-index:999}
::selection{background:var(--brand-glow);color:var(--text-main)}
::-webkit-scrollbar{width:10px;height:10px}
::-webkit-scrollbar-track{background:var(--bg-soft)}
::-webkit-scrollbar-thumb{background:var(--border);border-radius:var(--radius-pill)}
::-webkit-scrollbar-thumb:hover{background:var(--brand-light)}

/* header */
.site-header{
  position:sticky;top:0;z-index:100;
  background:var(--glass);
  backdrop-filter:blur(14px) saturate(180%);
  -webkit-backdrop-filter:blur(14px) saturate(180%);
  border-bottom:1px solid var(--glass-border);
  box-shadow:var(--shadow);
  transition:background-color .35s ease,border-color .35s ease;
}
.header-inner{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:12px 0;flex-wrap:wrap}
.logo{
  display:flex;align-items:center;gap:10px;
  font-size:1.3rem;font-weight:800;color:var(--brand);
  white-space:nowrap;transition:transform .25s ease;
}
.logo:hover{transform:translateY(-2px);text-decoration:none}
.logo svg{
  width:38px;height:38px;flex:0 0 auto;
  border-radius:10px;
  box-shadow:0 6px 16px var(--brand-glow);
  transition:transform .35s cubic-bezier(.34,1.56,.64,1);
}
.logo:hover svg{transform:rotate(-6deg) scale(1.06)}
.logo span{color:var(--text-main)}
.main-nav ul{display:flex;gap:20px;list-style:none;margin:0;flex-wrap:wrap}
.main-nav a{
  color:var(--text-sub);font-weight:600;font-size:.95rem;
  position:relative;padding:4px 0;
}
.main-nav a::after{
  content:"";position:absolute;left:0;right:100%;bottom:0;height:2px;
  background:linear-gradient(90deg,var(--brand),var(--accent));
  border-radius:2px;transition:right .28s ease;
}
.main-nav a:hover,.main-nav a:focus{color:var(--brand);text-decoration:none}
.main-nav a:hover::after,.main-nav a:focus::after{right:0}
.header-tools{display:flex;align-items:center;gap:10px}
.search-box{
  display:flex;align-items:center;
  border:1px solid var(--border);border-radius:var(--radius-pill);
  overflow:hidden;background:var(--bg-card);
  transition:border-color .25s ease,box-shadow .25s ease;
}
.search-box:focus-within{border-color:var(--brand);box-shadow:0 0 0 3px var(--brand-glow)}
.search-box input{border:0;outline:0;padding:8px 14px;font-size:.9rem;width:150px;background:transparent;color:var(--text-main)}
.search-box input::placeholder{color:var(--text-muted)}
.search-box button{
  border:0;background:linear-gradient(135deg,var(--brand),var(--brand-light));
  color:var(--btn-text);padding:8px 16px;cursor:pointer;font-size:.9rem;font-weight:600;
  transition:filter .2s ease;
}
.search-box button:hover{filter:brightness(1.1)}
.theme-btn,.menu-btn{
  border:1px solid var(--border);background:var(--bg-card);color:var(--text-sub);
  border-radius:var(--radius-sm);padding:8px 12px;cursor:pointer;font-size:.9rem;font-weight:600;
  transition:all .25s ease;
}
.theme-btn:hover,.menu-btn:hover{color:var(--brand);border-color:var(--brand);transform:translateY(-1px);box-shadow:var(--shadow)}
.menu-btn{display:none}

/* banner */
.banner{
  position:relative;
  background:linear-gradient(135deg,#0B2E5C 0%,var(--brand-dark) 35%,var(--brand) 70%,var(--brand-light) 100%);
  color:#fff;overflow:hidden;
}
.banner::before{
  content:"";position:absolute;inset:0;
  background:
    radial-gradient(circle at 12% 20%,rgba(255,255,255,.18),transparent 42%),
    radial-gradient(circle at 88% 78%,rgba(245,158,11,.22),transparent 46%),
    radial-gradient(circle at 60% 10%,rgba(127,180,242,.20),transparent 40%);
  pointer-events:none;
  animation:bannerShift 14s ease-in-out infinite alternate;
}
@keyframes bannerShift{
  0%{transform:translate3d(0,0,0) scale(1)}
  100%{transform:translate3d(-2%,1.5%,0) scale(1.06)}
}
.banner-slides{position:relative;min-height:340px;z-index:1}
.banner-slide{display:none;padding:60px 0;animation:fadeSlide .6s ease both}
.banner-slide.active{display:block}
@keyframes fadeSlide{
  from{opacity:0;transform:translateY(16px)}
  to{opacity:1;transform:none}
}
.banner h1,.banner h2,.banner p{color:#FFFFFF}
.banner h1{font-size:2.1rem;margin-bottom:.5em;text-shadow:0 2px 18px rgba(0,0,0,.22)}
.banner h2{font-size:1.7rem;margin-bottom:.5em;padding-bottom:0;text-shadow:0 2px 18px rgba(0,0,0,.22)}
.banner h2::after{display:none}
.banner p{font-size:1.05rem;max-width:720px;color:#EAF1FA}
.banner .kicker{
  display:inline-block;
  background:rgba(255,255,255,.14);
  backdrop-filter:blur(8px);
  -webkit-backdrop-filter:blur(8px);
  border:1px solid rgba(255,255,255,.35);
  color:#FFFFFF;padding:4px 14px;border-radius:var(--radius-pill);
  font-size:.85rem;margin-bottom:14px;
  box-shadow:0 4px 14px rgba(0,0,0,.12);
}
.banner-actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:18px}
.btn{
  display:inline-block;padding:11px 24px;border-radius:var(--radius-sm);
  font-weight:700;font-size:.95rem;cursor:pointer;border:1px solid transparent;
  transition:transform .25s ease,box-shadow .25s ease,background-color .25s ease,color .25s ease;
}
.btn:hover{text-decoration:none;transform:translateY(-2px)}
.btn-primary{
  background:#FFFFFF;color:var(--brand-dark);
  box-shadow:0 8px 22px rgba(0,0,0,.18);
}
.btn-primary:hover{background:#EAF1FA;color:var(--brand-dark);box-shadow:0 12px 28px rgba(0,0,0,.24)}
.btn-ghost{
  background:rgba(255,255,255,.08);
  backdrop-filter:blur(8px);
  -webkit-backdrop-filter:blur(8px);
  color:#FFFFFF;border-color:rgba(255,255,255,.7);
}
.btn-ghost:hover{background:rgba(255,255,255,.18);color:#FFFFFF;box-shadow:0 10px 26px rgba(0,0,0,.2)}
.banner-dots{display:flex;gap:8px;justify-content:center;padding-bottom:24px;position:relative;z-index:1}
.banner-dots button{
  width:11px;height:11px;border-radius:50%;border:0;
  background:rgba(255,255,255,.45);cursor:pointer;
  transition:transform .25s ease,background-color .25s ease,width .25s ease;
}
.banner-dots button:hover{background:rgba(255,255,255,.75)}
.banner-dots button.active{background:#FFFFFF;width:26px;border-radius:var(--radius-pill)}

/* breadcrumb */
.breadcrumb{background:var(--bg-soft);border-bottom:1px solid var(--border)}
.breadcrumb ol{display:flex;flex-wrap:wrap;list-style:none;margin:0;padding:12px 0;font-size:.88rem;gap:6px}
.breadcrumb li{color:var(--text-muted);margin:0}
.breadcrumb a{color:var(--link)}
.breadcrumb li+li::before{content:"›";margin-right:6px;color:var(--text-muted)}

/* anchor nav */
.anchor-nav{
  background:var(--glass);
  backdrop-filter:blur(14px) saturate(180%);
  -webkit-backdrop-filter:blur(14px) saturate(180%);
  border:1px solid var(--glass-border);
  border-radius:var(--radius);padding:16px 18px;margin:26px 0;
  box-shadow:var(--shadow);
}
.anchor-nav strong{display:block;color:var(--text-main);margin-bottom:10px}
.anchor-nav ul{display:flex;flex-wrap:wrap;gap:10px 18px;list-style:none;margin:0}
.anchor-nav a{
  font-size:.9rem;font-weight:600;color:var(--link);
  padding:3px 10px;border-radius:var(--radius-pill);
  transition:background-color .22s ease,color .22s ease;
}
.anchor-nav a:hover{background:var(--accent-soft);color:var(--link-hover);text-decoration:none}

/* cards */
.grid{display:grid;gap:22px}
.grid-2{grid-template-columns:repeat(2,1fr)}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-4{grid-template-columns:repeat(4,1fr)}
.card{
  background:var(--bg-card);
  border:1px solid var(--border);
  border-radius:var(--radius);padding:24px;
  box-shadow:var(--shadow);
  position:relative;overflow:hidden;
  transition:transform .3s cubic-bezier(.34,1.3,.64,1),box-shadow .3s ease,border-color .3s ease;
}
.card::before{
  content:"";position:absolute;inset:0 0 auto 0;height:3px;
  background:linear-gradient(90deg,var(--brand),var(--brand-light),var(--accent));
  transform:scaleX(0);transform-origin:left;
  transition:transform .35s ease;
}
.card:hover{transform:translateY(-6px);box-shadow:var(--shadow-lg);border-color:var(--brand-light)}
.card:hover::before{transform:scaleX(1)}
.card h3{color:var(--text-main)}
.card h4{margin-top:0}
.card p{color:var(--text-body);font-size:.95rem;margin-bottom:0}
.card .tag{
  display:inline-block;
  background:linear-gradient(135deg,var(--accent-soft),transparent);
  color:var(--brand-dark);
  border:1px solid var(--border);border-radius:var(--radius-pill);
  font-size:.78rem;padding:2px 12px;margin-bottom:10px;font-weight:700;
}
html[data-theme="dark"] .card .tag{color:var(--brand-light)}

/* stats */
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;text-align:center}
.stats>div{
  background:var(--bg-card);border:1px solid var(--border);
  border-radius:var(--radius);padding:22px 12px;
  box-shadow:var(--shadow);
  transition:transform .3s ease,box-shadow .3s ease;
}
.stats>div:hover{transform:translateY(-5px);box-shadow:var(--shadow-lg)}
.stat-num{
  font-size:2rem;font-weight:800;
  background:linear-gradient(135deg,var(--brand),var(--brand-light),var(--accent));
  -webkit-background-clip:text;background-clip:text;
  -webkit-text-fill-color:transparent;color:var(--brand);
}
.stat-label{color:var(--text-sub);font-size:.92rem}

/* article list */
.article-item{
  background:var(--bg-card);border:1px solid var(--border);
  border-radius:var(--radius);padding:24px;box-shadow:var(--shadow);
  margin-bottom:20px;
  transition:transform .3s ease,box-shadow .3s ease,border-color .3s ease;
}
.article-item:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);border-color:var(--brand-light)}
.article-item h3{margin-top:0;margin-bottom:6px}
.article-meta{font-size:.85rem;color:var(--text-muted);margin-bottom:10px}
.article-item p{font-size:.95rem;color:var(--text-body)}
.read-more{
  font-weight:700;color:var(--link);display:inline-flex;align-items:center;gap:6px;
  transition:gap .25s ease,color .2s ease;
}
.read-more::after{content:"→";transition:transform .25s ease}
.read-more:hover{gap:10px}
.read-more:hover::after{transform:translateX(3px)}

/* FAQ */
.faq-item{
  border:1px solid var(--border);border-radius:var(--radius-sm);
  margin-bottom:12px;background:var(--bg-card);overflow:hidden;
  transition:box-shadow .28s ease,border-color .28s ease;
}
.faq-item:hover{border-color:var(--brand-light);box-shadow:var(--shadow)}
.faq-q{
  width:100%;text-align:left;background:transparent;border:0;
  padding:16px 18px;font-size:1rem;font-weight:700;color:var(--text-main);
  cursor:pointer;display:flex;justify-content:space-between;gap:12px;align-items:flex-start;
  transition:color .22s ease,background-color .22s ease;
}
.faq-q:hover{color:var(--brand);background:var(--accent-soft)}
.faq-q .icon{
  flex:0 0 auto;color:var(--brand);font-weight:800;
  width:24px;height:24px;line-height:22px;text-align:center;
  border:1px solid var(--border);border-radius:50%;
  transition:transform .3s ease,background-color .3s ease,color .3s ease;
}
.faq-item.open .faq-q .icon{transform:rotate(180deg);background:var(--brand);color:var(--btn-text);border-color:var(--brand)}
.faq-a{display:none;padding:0 18px 16px;color:var(--text-body);font-size:.95rem;animation:fadeSlide .35s ease both}
.faq-item.open .faq-a{display:block}

/* table */
table{
  width:100%;border-collapse:collapse;margin:18px 0;font-size:.93rem;
  background:var(--bg-card);border-radius:var(--radius-sm);overflow:hidden;
  box-shadow:var(--shadow);
}
caption{caption-side:top;text-align:left;color:var(--text-sub);font-weight:700;padding-bottom:8px}
th,td{border:1px solid var(--border);padding:11px 14px;text-align:left;color:var(--text-body)}
th{background:var(--bg-soft);color:var(--text-main);font-weight:700}
tbody tr{transition:background-color .22s ease}
tbody tr:hover{background:var(--accent-soft)}

/* steps */
.steps{counter-reset:step;list-style:none;margin:0;padding:0}
.steps li{position:relative;padding:0 0 22px 52px;color:var(--text-body)}
.steps li::before{
  counter-increment:step;content:counter(step);
  position:absolute;left:0;top:0;width:34px;height:34px;border-radius:50%;
  background:linear-gradient(135deg,var(--brand),var(--brand-light));
  color:var(--btn-text);font-weight:800;
  display:flex;align-items:center;justify-content:center;
  box-shadow:0 6px 16px var(--brand-glow);
  transition:transform .28s ease;
}
.steps li:hover::before{transform:scale(1.12) rotate(-6deg)}
.steps li:not(:last-child)::after{
  content:"";position:absolute;left:16px;top:36px;bottom:0;width:2px;
  background:linear-gradient(180deg,var(--brand-light),transparent);
}

/* contact */
.contact-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:18px}
.contact-item{
  background:var(--bg-card);border:1px solid var(--border);
  border-radius:var(--radius-sm);padding:20px;
  transition:transform .28s ease,box-shadow .28s ease,border-color .28s ease;
}
.contact-item:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);border-color:var(--brand-light)}
.contact-item strong{display:block;color:var(--text-main);margin-bottom:4px}
.contact-item span,.contact-item a{color:var(--text-body);font-size:.95rem}

/* footer */
.site-footer{
  background:linear-gradient(180deg,var(--footer-bg),#0B1524);
  color:var(--footer-text);padding:46px 0 20px;margin-top:20px;
  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(--brand-light),var(--accent));
}
.site-footer h3,.site-footer h4{color:#FFFFFF}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1.3fr;gap:26px}
.site-footer p,.site-footer li{color:var(--footer-text);font-size:.9rem}
.site-footer a{color:var(--footer-sub);transition:color .2s ease,padding-left .2s ease}
.site-footer a:hover,.site-footer a:focus{color:#FFFFFF;padding-left:4px}
.footer-links{list-style:none;margin:0}
.footer-bottom{
  border-top:1px solid rgba(255,255,255,.18);
  margin-top:26px;padding-top:18px;font-size:.85rem;color:var(--footer-sub);
  display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap;
}

/* back to top */
#backTop{
  position:fixed;right:20px;bottom:26px;width:46px;height:46px;border-radius:50%;
  border:0;background:linear-gradient(135deg,var(--brand),var(--brand-light));
  color:var(--btn-text);font-size:1.2rem;font-weight:800;cursor:pointer;
  display:none;z-index:120;box-shadow:0 10px 26px var(--brand-glow);
  transition:transform .28s ease,filter .28s ease;
}
#backTop:hover{transform:translateY(-4px) scale(1.06);filter:brightness(1.1)}

/* reveal */
.reveal{opacity:0;transform:translateY(22px);transition:opacity .7s ease,transform .7s cubic-bezier(.22,1,.36,1)}
.reveal.visible{opacity:1;transform:none}

@media(max-width:960px){
  .grid-4,.grid-3,.stats{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:1fr 1fr}
  h1{font-size:1.8rem}
  h2{font-size:1.4rem}
}
@media(max-width:720px){
  body{font-size:15px}
  section{padding:40px 0}
  .main-nav{display:none;width:100%;order:4}
  .main-nav.open{display:block;animation:fadeSlide .35s ease both}
  .main-nav ul{flex-direction:column;gap:0;border-top:1px solid var(--border);padding-top:10px}
  .main-nav li{padding:8px 0}
  .main-nav a::after{display:none}
  .menu-btn{display:inline-block}
  .grid-2,.grid-3,.grid-4,.stats,.contact-grid{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr}
  .banner h1{font-size:1.55rem}
  .banner h2{font-size:1.3rem}
  .banner p{font-size:.98rem}
  .banner-slide{padding:44px 0}
  .banner-slides{min-height:300px}
  .search-box input{width:110px}
  .header-inner{gap:10px}
  .btn{padding:10px 18px;font-size:.9rem}
  table{font-size:.85rem}
  th,td{padding:9px 10px}
  #backTop{right:14px;bottom:18px;width:42px;height:42px}
}
@media(max-width:420px){
  .search-box input{width:84px}
  .logo{font-size:1.15rem}
  .logo svg{width:32px;height:32px}
  h1{font-size:1.4rem}
  .banner h1{font-size:1.35rem}
}
@media(prefers-reduced-motion:reduce){
  *{animation-duration:.001ms !important;animation-iteration-count:1 !important;transition-duration:.001ms !important;scroll-behavior:auto !important}
  .reveal{opacity:1;transform:none}
}
@media print{
  .site-header,.banner,#backTop,.anchor-nav,.site-footer{display:none}
  body{color:#000;background:#fff}
}