/* ===== Reset & Base ===== */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%;text-size-adjust:100%}
body{min-height:100vh;background:var(--bg-dark);color:var(--text-primary);font-family:var(--font-body);font-weight:var(--weight-body);font-size:var(--base-size);line-height:1.6;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}
img{display:block;max-width:100%;height:auto}
a{color:inherit;text-decoration:none}
ul,ol{list-style:none}
button,input,select,textarea{font:inherit;color:inherit;border:none;background:none;cursor:pointer}
button:focus-visible,input:focus-visible,select:focus-visible,textarea:focus-visible{outline:2px solid var(--primary-orange);outline-offset:2px}
:focus-visible{outline:2px solid var(--primary-orange);outline-offset:2px}
::selection{background:var(--primary-orange);color:#fff}
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:0.01ms!important;animation-iteration-count:1!important;transition-duration:0.01ms!important;scroll-behavior:auto!important}
  html{scroll-behavior:auto}
}

/* ===== CSS Variables ===== */
:root{
  --primary-dark:#0B1A33;
  --primary-orange:#FF6B35;
  --accent-yellow:#FFD166;
  --bg-dark:#0F1C3D;
  --bg-card:#1A2D4A;
  --text-primary:#FFFFFF;
  --text-secondary:#B0C4DE;
  --highlight-grad:linear-gradient(135deg,#FF6B35,#FFD166);
  --border-glow:rgba(255,107,53,0.4);
  --font-heading:'Poppins','Noto Sans SC','PingFang SC','Microsoft YaHei',sans-serif;
  --font-body:'Inter','Noto Sans SC','PingFang SC','Microsoft YaHei',sans-serif;
  --weight-heading:800;
  --weight-body:400;
  --base-size:16px;
  --scale:1.25;
  --space-xs:0.25rem;
  --space-sm:0.5rem;
  --space-md:1rem;
  --space-lg:2rem;
  --space-xl:3rem;
  --space-2xl:5rem;
  --radius-sm:4px;
  --radius-md:8px;
  --radius-lg:16px;
  --header-h:64px;
  --max-w:1200px;
  --grid-gap:1.5rem;
  --z-nav:100;
  --z-hero:1;
  --z-card:10;
  --z-modal:200;
  --z-progress:150;
}

/* ===== Typography ===== */
h1,h2,h3,h4,h5,h6{font-family:var(--font-heading);font-weight:var(--weight-heading);line-height:1.2;letter-spacing:-0.02em}
h1{font-size:calc(var(--base-size)*var(--scale)*var(--scale)*var(--scale))} /* ~31px */
h2{font-size:calc(var(--base-size)*var(--scale)*var(--scale))} /* 25px */
h3{font-size:calc(var(--base-size)*var(--scale))} /* 20px */
h4{font-size:var(--base-size);font-weight:700}
p,li,span,label{font-family:var(--font-body);font-weight:var(--weight-body);color:var(--text-secondary)}
strong,b{font-weight:700;color:var(--text-primary)}
small,.text-small{font-size:0.875rem}
.text-large{font-size:1.125rem}
.text-secondary{color:var(--text-secondary)}
.text-primary{color:var(--text-primary)}
.text-accent{color:var(--primary-orange)}
.text-center{text-align:center}
.section-title{
  font-size:calc(var(--base-size)*var(--scale)*var(--scale));
  padding-left:var(--space-md);
  border-left:4px solid var(--primary-orange);
  margin-bottom:var(--space-lg);
  letter-spacing:-0.02em;
}

/* ===== Container & Grid ===== */
.container{width:100%;max-width:var(--max-w);margin-inline:auto;padding-inline:var(--space-lg)}
@media(max-width:768px){.container{padding-inline:var(--space-md)}}
.grid{display:grid;grid-template-columns:repeat(12,1fr);gap:var(--grid-gap)}
.grid-2{grid-template-columns:repeat(2,1fr)}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-4{grid-template-columns:repeat(4,1fr)}
@media(max-width:1024px){.grid-3,.grid-4{grid-template-columns:repeat(2,1fr)}}
@media(max-width:768px){.grid-2,.grid-3,.grid-4{grid-template-columns:1fr}}

/* ===== Skip Link ===== */
.skip-link{
  position:fixed;top:-100px;left:16px;z-index:300;
  background:var(--primary-orange);color:#fff;
  padding:8px 16px;border-radius:var(--radius-md);
  font-size:0.875rem;font-weight:700;
  transition:top 0.3s;
}
.skip-link:focus{top:16px}

/* ===== Header ===== */
.site-header{
  position:fixed;top:0;left:0;width:100%;z-index:var(--z-nav);
  background:transparent;
  transition:background 0.4s ease,box-shadow 0.4s ease;
  will-change:background;
}
.site-header[data-scrolled]{
  background:var(--bg-dark);
  box-shadow:0 2px 24px rgba(0,0,0,0.5);
}
.header-inner{
  display:flex;align-items:center;justify-content:space-between;
  height:var(--header-h);position:relative;z-index:2;
}
.brand{flex-shrink:0;display:flex;align-items:center;gap:var(--space-sm);z-index:3}
.brand-svg{height:32px;width:auto;display:block}
.nav{display:flex;align-items:center}
.nav-list{display:flex;gap:var(--space-xs)}
.nav-link{
  display:block;padding:var(--space-sm) var(--space-md);
  font-family:var(--font-heading);font-weight:600;font-size:0.9375rem;
  color:var(--text-secondary);border-radius:var(--radius-sm);
  transition:color 0.3s,background 0.3s,box-shadow 0.3s;
  letter-spacing:0.01em;position:relative;
}
.nav-link:hover{color:var(--text-primary);background:rgba(255,255,255,0.06)}
.nav-link[aria-current="page"]{
  color:var(--primary-orange);
  background:rgba(255,107,53,0.08);
  box-shadow:inset 0 -2px 0 var(--primary-orange);
}
.header-cta{flex-shrink:0;margin-left:var(--space-md);z-index:3}
.nav-toggle{display:none;flex-direction:column;justify-content:center;align-items:center;width:40px;height:40px;gap:5px;z-index:3;background:transparent;border:none;cursor:pointer}
.nav-toggle-line{display:block;width:24px;height:2.5px;background:var(--text-primary);border-radius:2px;transition:transform 0.3s,opacity 0.3s;transform-origin:center}
.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(1){transform:translateY(7.5px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(2){opacity:0}
.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(3){transform:translateY(-7.5px) rotate(-45deg)}

/* ===== Progress Bar ===== */
.progress-bar{
  position:absolute;bottom:0;left:0;width:0%;height:3px;
  background:var(--highlight-grad);
  transition:width 0.1s linear;
  z-index:var(--z-progress);
  opacity:0;
}
.site-header[data-scrolled] .progress-bar{opacity:1}

/* ===== Mobile Nav ===== */
@media(max-width:768px){
  .nav-toggle{display:flex}
  .header-cta{display:none}
  .nav{
    position:fixed;top:0;right:-100%;width:280px;height:100vh;
    background:var(--bg-dark);flex-direction:column;align-items:stretch;
    justify-content:flex-start;padding:calc(var(--header-h)+var(--space-lg)) var(--space-lg) var(--space-lg);
    box-shadow:-4px 0 24px rgba(0,0,0,0.6);
    transition:right 0.35s cubic-bezier(0.4,0,0.2,1);
    z-index:var(--z-nav);
  }
  .nav[data-open]{right:0}
  .nav-list{flex-direction:column;gap:var(--space-sm)}
  .nav-link{padding:var(--space-md);font-size:1.05rem;border-radius:var(--radius-md)}
  .nav-link[aria-current="page"]{background:rgba(255,107,53,0.12);box-shadow:none}
  .header-cta.mobile-visible{display:inline-flex;margin:var(--space-lg) 0 0;width:100%;justify-content:center}
  .nav[data-open] ~ .header-cta{display:none}
}

/* ===== Footer ===== */
.site-footer{
  background:var(--primary-dark);
  border-top:2px solid rgba(255,107,53,0.15);
  padding:var(--space-2xl) 0 0;
  margin-top:var(--space-2xl);
}
.footer-inner{display:grid;grid-template-columns:2fr 1fr 3fr;gap:var(--space-xl);align-items:start}
.footer-brand-svg{height:28px;width:auto;display:block;margin-bottom:var(--space-sm)}
.footer-tagline{font-size:0.95rem;color:var(--text-secondary);margin-top:var(--space-sm)}
.footer-links{display:flex;flex-direction:column;gap:var(--space-sm);padding-top:var(--space-sm)}
.footer-link{
  font-size:0.9375rem;color:var(--text-secondary);transition:color 0.3s;position:relative;
  padding-left:var(--space-md);
}
.footer-link::before{
  content:'';position:absolute;left:0;top:50%;transform:translateY(-50%);
  width:6px;height:6px;background:var(--primary-orange);border-radius:1px;
  transition:transform 0.3s;
}
.footer-link:hover{color:var(--primary-orange)}
.footer-link:hover::before{transform:translateY(-50%) scale(1.3)}
.footer-info{font-size:0.875rem;line-height:1.8;padding-top:var(--space-sm)}
.footer-contact,.footer-note,.footer-icp{color:var(--text-secondary);margin-bottom:var(--space-xs)}
.footer-icp{font-size:0.8125rem;opacity:0.7;margin-top:var(--space-sm)}
.footer-bar{
  margin-top:var(--space-xl);border-top:1px solid rgba(255,255,255,0.06);
  padding:var(--space-md) 0;
}
.footer-bar-inner{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:var(--space-sm)}
.footer-copy{font-size:0.8125rem;color:var(--text-secondary);opacity:0.7}
.footer-trust{font-size:0.8125rem;color:var(--text-secondary);opacity:0.5;text-align:right}
@media(max-width:768px){
  .footer-inner{grid-template-columns:1fr;gap:var(--space-lg)}
  .footer-bar-inner{flex-direction:column;text-align:center}
  .footer-trust{text-align:center}
}

/* ===== Buttons ===== */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:var(--space-sm);
  padding:0.625rem 1.5rem;border-radius:var(--radius-md);
  font-family:var(--font-heading);font-weight:700;font-size:0.9375rem;
  transition:transform 0.25s,box-shadow 0.3s,background 0.3s;
  cursor:pointer;text-align:center;white-space:nowrap;
  border:2px solid transparent;letter-spacing:0.01em;
}
.btn:hover{transform:translateY(-2px);box-shadow:0 6px 20px rgba(255,107,53,0.3)}
.btn:active{transform:scale(0.97);box-shadow:none}
.btn-primary{
  background:var(--highlight-grad);color:#fff;border-color:transparent;
  box-shadow:0 4px 16px rgba(255,107,53,0.25);
}
.btn-primary:hover{box-shadow:0 8px 28px rgba(255,107,53,0.4)}
.btn-secondary{
  background:transparent;color:var(--text-primary);border-color:var(--border-glow);
  box-shadow:0 0 0 1px var(--border-glow);
}
.btn-secondary:hover{background:rgba(255,107,53,0.06);border-color:var(--primary-orange)}
.btn-sm{padding:0.4rem 1rem;font-size:0.8125rem}
.btn-lg{padding:0.875rem 2.25rem;font-size:1.0625rem}

/* ===== Card ===== */
.card{
  background:var(--bg-card);border-radius:var(--radius-lg);
  padding:var(--space-lg);border:1px solid rgba(255,255,255,0.04);
  transition:box-shadow 0.3s,transform 0.3s;
  clip-path:polygon(0 0,100% 0,100% calc(100% - 12px),calc(100% - 12px) 100%,0 100%);
}
.card:hover{box-shadow:0 0 0 2px var(--border-glow),0 8px 32px rgba(0,0,0,0.3);transform:translateY(-4px)}
.card-title{font-size:1.125rem;margin-bottom:var(--space-sm);color:var(--text-primary)}
.card-text{font-size:0.9375rem;color:var(--text-secondary);line-height:1.6}
.card-badge{display:inline-block;background:var(--primary-orange);color:#fff;font-size:0.75rem;font-weight:700;padding:0.2rem 0.6rem;border-radius:var(--radius-sm);margin-bottom:var(--space-sm);letter-spacing:0.03em}

/* ===== Badge ===== */
.badge{
  display:inline-flex;align-items:center;gap:4px;
  background:var(--highlight-grad);color:#fff;
  font-size:0.75rem;font-weight:700;padding:0.2rem 0.65rem;
  border-radius:var(--radius-sm);letter-spacing:0.02em;
  white-space:nowrap;
}
.badge-outline{background:transparent;border:1.5px solid var(--primary-orange);color:var(--primary-orange)}

/* ===== Divider ===== */
.divider{
  position:relative;height:2px;background:transparent;
  margin:var(--space-xl) 0;overflow:visible;
}
.divider::before{
  content:'';position:absolute;top:0;left:0;
  width:60px;height:100%;background:var(--highlight-grad);
  border-radius:2px;
}
.divider::after{
  content:'';position:absolute;top:-6px;left:70px;
  width:20px;height:14px;background:var(--highlight-grad);
  clip-path:polygon(0 0,100% 50%,0 100%);
  opacity:0.6;
}
.divider-center::before{left:50%;transform:translateX(-50%)}
.divider-center::after{left:calc(50%+10px);transform:translateX(-50%)}

/* ===== Image Container ===== */
.image-cover{
  position:relative;overflow:hidden;border-radius:var(--radius-md);
  background:var(--bg-card);aspect-ratio:16/9;
}
.image-cover img{position:absolute;top:0;left:0;width:100%;height:100%;object-fit:cover}
.image-cover.square{aspect-ratio:1/1}
.image-cover.wide{aspect-ratio:21/9}
.image-cover::after{
  content:'';position:absolute;bottom:0;left:0;width:100%;height:30%;
  background:linear-gradient(transparent,rgba(0,0,0,0.5));
  pointer-events:none;
}
.image-cover .image-label{
  position:absolute;bottom:var(--space-sm);left:var(--space-sm);
  color:#fff;font-size:0.8125rem;font-weight:700;z-index:2;
  text-shadow:0 2px 8px rgba(0,0,0,0.6);
}

/* ===== Decorative Elements ===== */
.corner-accent{
  position:relative;
}
.corner-accent::before{
  content:'';position:absolute;top:-6px;right:-6px;
  width:18px;height:18px;border-top:3px solid var(--primary-orange);
  border-right:3px solid var(--primary-orange);
  border-radius:0 4px 0 0;pointer-events:none;
}
.corner-accent::after{
  content:'';position:absolute;bottom:-6px;left:-6px;
  width:18px;height:18px;border-bottom:3px solid var(--accent-yellow);
  border-left:3px solid var(--accent-yellow);
  border-radius:0 0 0 4px;pointer-events:none;
}

.slash-divider{
  position:relative;display:inline-block;
  padding-inline:var(--space-md);
}
.slash-divider::before{
  content:'//';color:var(--primary-orange);
  font-weight:700;font-size:0.75rem;letter-spacing:2px;
  opacity:0.5;margin-right:var(--space-sm);
}

/* ===== Back Top ===== */
.back-top{
  position:fixed;bottom:32px;right:32px;z-index:var(--z-modal);
  width:48px;height:48px;border-radius:50%;
  background:var(--bg-card);border:2px solid var(--border-glow);
  color:var(--text-primary);font-size:1.25rem;
  display:flex;align-items:center;justify-content:center;
  cursor:pointer;opacity:0;visibility:hidden;
  transform:translateY(20px);transition:opacity 0.35s,transform 0.35s,box-shadow 0.3s;
  box-shadow:0 4px 16px rgba(0,0,0,0.3);
}
.back-top[data-visible]{opacity:1;visibility:visible;transform:translateY(0)}
.back-top:hover{box-shadow:0 0 0 4px var(--border-glow),0 8px 24px rgba(0,0,0,0.4);background:var(--primary-dark)}
@media(max-width:768px){.back-top{bottom:20px;right:20px;width:44px;height:44px;font-size:1.1rem}}

/* ===== Responsive ===== */
@media(max-width:1024px){
  .footer-inner{grid-template-columns:1fr 1fr}
  .header-inner{gap:var(--space-sm)}
}
@media(max-width:768px){
  :root{--header-h:56px}
  .section-title{font-size:1.25rem}
  h1{font-size:1.75rem}
  h2{font-size:1.375rem}
  .header-cta{display:none}
  .nav .header-cta.mobile-visible{display:flex}
}
@media(min-width:769px){
  .mobile-visible{display:none!important}
  .nav .header-cta.mobile-visible{display:none!important}
}

/* ===== Scroll reveal base ===== */
[data-reveal]{opacity:0;transform:translateY(24px);transition:opacity 0.6s ease,transform 0.6s ease}
[data-reveal].revealed{opacity:1;transform:translateY(0)}
@media (prefers-reduced-motion:reduce){[data-reveal]{opacity:1;transform:none;transition:none}}

/* ===== Utility ===== */
.mt-sm{margin-top:var(--space-sm)}.mt-md{margin-top:var(--space-md)}.mt-lg{margin-top:var(--space-lg)}.mt-xl{margin-top:var(--space-xl)}
.mb-sm{margin-bottom:var(--space-sm)}.mb-md{margin-bottom:var(--space-md)}.mb-lg{margin-bottom:var(--space-lg)}.mb-xl{margin-bottom:var(--space-xl)}
.p-sm{padding:var(--space-sm)}.p-md{padding:var(--space-md)}.p-lg{padding:var(--space-lg)}
.flex{display:flex}.flex-col{flex-direction:column}.flex-wrap{flex-wrap:wrap}.items-center{align-items:center}.justify-between{justify-content:space-between}.gap-sm{gap:var(--space-sm)}.gap-md{gap:var(--space-md)}.gap-lg{gap:var(--space-lg)}
.w-full{width:100%}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}