/* === RESET & BASE === */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;font-size:16px;line-height:1.5;-webkit-text-size-adjust:100%}
body{font-family:'Inter','PingFang SC','Microsoft YaHei',sans-serif;background:#0B1A2E;color:#FFFFFF;min-height:100vh;overflow-x:hidden}
img{display:block;max-width:100%;height:auto}
a{color:inherit;text-decoration:none}
ul{list-style:none}
button{border:none;background:none;cursor:pointer;font:inherit;color:inherit}
:focus-visible{outline:2px solid #D4AF37;outline-offset:2px;border-radius:4px}
::selection{background:#D4AF37;color:#0B1A2E}

/* === CSS VARIABLES === */
:root{
  --color-primary-dark:#0B1A2E;
  --color-gold:#D4AF37;
  --color-accent-red:#E63946;
  --color-electric-blue:#00B4D8;
  --color-dark-gray:#2C3E50;
  --color-light-gray:#EAECEE;
  --color-text-white:#FFFFFF;
  --color-text-dark:#1A1A1A;
  --font-heading:'Inter','PingFang SC','Microsoft YaHei',sans-serif;
  --font-body:'Inter','PingFang SC','Microsoft YaHei',sans-serif;
  --font-mono:'JetBrains Mono','Courier New',monospace;
  --nav-width:280px;
  --header-height-mobile:64px;
  --radius-lg:24px;
  --radius-md:16px;
  --radius-sm:8px;
  --radius-pill:9999px;
  --transition:0.3s cubic-bezier(0.4,0,0.2,1);
  --shadow-card:0 4px 20px rgba(0,0,0,0.3);
  --shadow-hover:0 8px 32px rgba(0,0,0,0.5);
  --container-max:1280px;
  --gap:2rem;
}

/* === TYPOGRAPHY === */
h1,h2,h3,h4,h5,h6{font-family:var(--font-heading);font-weight:800;font-style:italic;line-height:1.2;color:var(--color-gold)}
h1{font-size:clamp(2rem,5vw,4rem)}
h2{font-size:clamp(1.6rem,3.5vw,2.8rem)}
h3{font-size:clamp(1.2rem,2.5vw,1.8rem)}
h4{font-size:clamp(1rem,1.8vw,1.4rem)}
p,li,span{font-family:var(--font-body);font-weight:400;font-size:1rem;line-height:1.7;letter-spacing:0.02em;color:var(--color-text-white)}
.data-number{font-family:var(--font-mono);font-weight:500;letter-spacing:0.02em}
.nav-label{font-family:var(--font-body);font-weight:600;text-transform:uppercase;letter-spacing:0.1em}

/* === SKIP LINK === */
.skip-link{position:absolute;top:-100%;left:0;z-index:1000;padding:0.75rem 1.5rem;background:var(--color-gold);color:var(--color-primary-dark);font-weight:700;border-radius:0 0 var(--radius-sm) 0;transition:top 0.2s}
.skip-link:focus{top:0;outline:none}

/* === CONTAINER === */
.container{width:100%;max-width:var(--container-max);margin:0 auto;padding-left:var(--gap);padding-right:var(--gap)}

/* === HEADER / SIDEBAR === */
.site-header{position:fixed;top:0;left:0;width:var(--nav-width);height:100vh;background:var(--color-primary-dark);z-index:900;display:flex;flex-direction:column;border-right:1px solid rgba(212,175,55,0.15);overflow-y:auto}
.header-inner{display:flex;flex-direction:column;height:100%;padding:2rem 1.5rem}
.header-brand{margin-bottom:3rem;text-align:center}
.brand-link{display:inline-block}
.brand-logo{font-family:var(--font-heading);font-weight:800;font-style:italic;font-size:1.8rem;color:var(--color-text-white);letter-spacing:0.05em}
.brand-highlight{color:var(--color-gold)}
.nav-toggle{display:none;position:absolute;top:1rem;right:1rem;width:40px;height:40px;align-items:center;justify-content:center;background:rgba(255,255,255,0.05);border-radius:var(--radius-sm);z-index:10}
.nav-toggle-line{display:block;width:22px;height:2px;background:var(--color-gold);margin:4px auto;border-radius:2px;transition:var(--transition)}
.site-nav{flex:1}
.nav-list{display:flex;flex-direction:column;gap:0.25rem}
.nav-item{margin:0}
.nav-link{display:block;padding:0.75rem 1rem;font-family:var(--font-body);font-weight:600;text-transform:uppercase;letter-spacing:0.1em;font-size:0.9rem;color:rgba(255,255,255,0.7);border-radius:var(--radius-sm);transition:var(--transition);position:relative}
.nav-link:hover{color:var(--color-gold);background:rgba(212,175,55,0.1);transform:translateX(4px)}
.nav-link[aria-current="page"]{color:var(--color-gold);background:rgba(212,175,55,0.12);font-weight:700;border-left:3px solid var(--color-gold);padding-left:calc(1rem - 3px)}
.nav-link[aria-current="page"]::after{content:'';position:absolute;right:1rem;top:50%;transform:translateY(-50%);width:6px;height:6px;border-radius:50%;background:var(--color-gold)}

/* === MAIN CONTENT WRAPPER === */
#main-content{min-height:calc(100vh - 200px);margin-left:var(--nav-width);padding:0}
@media(max-width:1024px){
  #main-content{margin-left:0;padding-top:var(--header-height-mobile)}
}

/* === FOOTER === */
.site-footer{background:var(--color-primary-dark);border-top:1px solid rgba(212,175,55,0.15);padding:3rem 0 2rem;margin-left:var(--nav-width)}
.footer-grid{max-width:var(--container-max);margin:0 auto;padding:0 var(--gap);display:grid;grid-template-columns:1.5fr 1fr 1.5fr;gap:2.5rem}
.footer-logo{font-family:var(--font-heading);font-weight:800;font-style:italic;font-size:1.6rem;color:var(--color-gold);display:inline-block;margin-bottom:1rem}
.footer-desc{font-size:0.9rem;color:rgba(255,255,255,0.65);line-height:1.7;max-width:320px}
.footer-heading{font-family:var(--font-body);font-weight:700;font-size:1rem;text-transform:uppercase;letter-spacing:0.1em;color:var(--color-gold);margin-bottom:1.2rem;font-style:normal}
.footer-links{display:flex;flex-direction:column;gap:0.6rem}
.footer-links a{font-size:0.9rem;color:rgba(255,255,255,0.65);transition:var(--transition)}
.footer-links a:hover{color:var(--color-gold);padding-left:4px}
.footer-contact-list{display:flex;flex-direction:column;gap:0.5rem;margin-bottom:1.2rem}
.footer-contact-list li{font-size:0.85rem;color:rgba(255,255,255,0.65);line-height:1.6}
.footer-legal{display:flex;flex-wrap:wrap;gap:0.4rem 0.8rem;margin-bottom:0.8rem}
.footer-legal a{font-size:0.85rem;color:rgba(255,255,255,0.5);transition:var(--transition)}
.footer-legal a:hover{color:var(--color-gold)}
.footer-legal-sep{color:rgba(255,255,255,0.2);font-size:0.75rem}
.footer-icp{font-size:0.75rem;color:rgba(255,255,255,0.35);letter-spacing:0.05em}
@media(max-width:1024px){
  .site-footer{margin-left:0}
  .footer-grid{grid-template-columns:1fr;gap:2rem}
  .footer-desc{max-width:100%}
}

/* === BUTTONS === */
.btn{display:inline-flex;align-items:center;justify-content:center;padding:0.7rem 2rem;font-family:var(--font-body);font-weight:600;font-size:0.95rem;border-radius:var(--radius-pill);transition:var(--transition);letter-spacing:0.03em;text-transform:uppercase}
.btn-primary{background:var(--color-gold);color:var(--color-primary-dark)}
.btn-primary:hover{background:#c49f2e;transform:translateY(-2px);box-shadow:0 6px 20px rgba(212,175,55,0.3)}
.btn-secondary{background:transparent;color:var(--color-gold);border:2px solid var(--color-gold)}
.btn-secondary:hover{background:rgba(212,175,55,0.1);transform:translateY(-2px)}

/* === CARDS === */
.card{background:var(--color-dark-gray);border-radius:var(--radius-lg);padding:1.8rem;box-shadow:var(--shadow-card);transition:var(--transition);border:1px solid rgba(212,175,55,0.08)}
.card:hover{box-shadow:var(--shadow-hover);transform:translateY(-4px);border-color:rgba(212,175,55,0.2)}
.card-title{font-family:var(--font-heading);font-weight:800;font-style:italic;font-size:1.2rem;color:var(--color-gold);margin-bottom:0.8rem}
.card-text{font-size:0.95rem;color:rgba(255,255,255,0.75);line-height:1.7}

/* === TAGS & BADGES === */
.tag{display:inline-block;padding:0.25rem 1rem;font-size:0.75rem;font-weight:600;text-transform:uppercase;letter-spacing:0.08em;border-radius:var(--radius-pill);background:rgba(212,175,55,0.15);color:var(--color-gold)}
.badge{display:inline-flex;align-items:center;justify-content:center;min-width:28px;height:28px;padding:0 0.6rem;font-family:var(--font-mono);font-size:0.8rem;font-weight:500;border-radius:var(--radius-pill);background:var(--color-accent-red);color:#fff}

/* === DIVIDER SKEW === */
.divider-skew{width:100%;height:60px;background:transparent;position:relative;margin:2rem 0}
.divider-skew::before{content:'';display:block;width:100%;height:100%;background:linear-gradient(135deg,rgba(212,175,55,0.08) 0%,transparent 60%);clip-path:polygon(0 40%,100% 0,100% 60%,0 100%);position:absolute;top:0;left:0}

/* === BREADCRUMB === */
.breadcrumb{display:flex;flex-wrap:wrap;gap:0.5rem;align-items:center;padding:0.8rem 0;margin-bottom:1rem}
.breadcrumb-item{font-size:0.85rem;color:rgba(255,255,255,0.5)}
.breadcrumb-item a{color:rgba(255,255,255,0.6);transition:var(--transition)}
.breadcrumb-item a:hover{color:var(--color-gold)}
.breadcrumb-sep{color:rgba(255,255,255,0.2);margin:0 0.25rem;font-size:0.7rem}

/* === DATA NUMBER === */
.data-number{font-family:var(--font-mono);font-weight:500;color:var(--color-accent-red);font-size:1.2em}

/* === SCROLL TOP === */
.scroll-top{position:fixed;bottom:2rem;right:2rem;width:48px;height:48px;border-radius:50%;background:var(--color-gold);color:var(--color-primary-dark);font-size:1.4rem;display:flex;align-items:center;justify-content:center;box-shadow:0 4px 16px rgba(212,175,55,0.3);opacity:0;visibility:hidden;transform:translateY(20px);transition:var(--transition);z-index:800}
.scroll-top.visible{opacity:1;visibility:visible;transform:translateY(0)}
.scroll-top:hover{background:#c49f2e;transform:translateY(-4px);box-shadow:0 6px 24px rgba(212,175,55,0.5)}
@media(max-width:1024px){
  .scroll-top{bottom:1.5rem;right:1.5rem;width:44px;height:44px;font-size:1.2rem}
}

/* === RESPONSIVE: TABLET & MOBILE === */
@media(max-width:1024px){
  .site-header{position:fixed;top:0;left:0;width:100%;height:var(--header-height-mobile);flex-direction:row;align-items:center;padding:0;border-right:none;border-bottom:1px solid rgba(212,175,55,0.15);overflow:visible}
  .header-inner{flex-direction:row;align-items:center;justify-content:space-between;width:100%;height:100%;padding:0 1.25rem}
  .header-brand{margin-bottom:0;text-align:left}
  .brand-logo{font-size:1.4rem}
  .nav-toggle{display:flex;position:relative;top:auto;right:auto}
  .site-nav{position:fixed;top:var(--header-height-mobile);left:-100%;width:300px;max-width:80vw;height:calc(100vh - var(--header-height-mobile));background:var(--color-primary-dark);flex-direction:column;padding:1.5rem 1.25rem;transition:left 0.35s cubic-bezier(0.4,0,0.2,1);z-index:950;border-right:1px solid rgba(212,175,55,0.1);overflow-y:auto;box-shadow:4px 0 30px rgba(0,0,0,0.6)}
  .site-nav[data-open]{left:0}
  .nav-list{gap:0.15rem}
  .nav-link{font-size:0.95rem;padding:0.8rem 1rem}
  .nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(1){transform:translateY(6px) 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(-6px) rotate(-45deg)}
}

/* === OVERLAY FOR MOBILE NAV === */
.nav-overlay{display:none;position:fixed;top:0;left:0;width:100%;height:100%;background:rgba(0,0,0,0.5);z-index:940;backdrop-filter:blur(2px)}
.nav-overlay.active{display:block}
@media(min-width:1025px){
  .nav-overlay{display:none!important}
}

/* === UTILITY === */
.text-gold{color:var(--color-gold)}
.text-red{color:var(--color-accent-red)}
.text-blue{color:var(--color-electric-blue)}
.text-muted{color:rgba(255,255,255,0.5)}
.mt-1{margin-top:1rem}
.mt-2{margin-top:2rem}
.mb-1{margin-bottom:1rem}
.mb-2{margin-bottom:2rem}
.p-1{padding:1rem}
.p-2{padding:2rem}
.flex{display:flex}
.flex-col{flex-direction:column}
.items-center{align-items:center}
.justify-between{justify-content:space-between}
.gap-1{gap:1rem}
.gap-2{gap:2rem}
.grid-2{display:grid;grid-template-columns:1fr 1fr;gap:var(--gap)}
.grid-3{display:grid;grid-template-columns:1fr 1fr 1fr;gap:var(--gap)}
@media(max-width:768px){
  .grid-2,.grid-3{grid-template-columns:1fr}
  .container{padding-left:1rem;padding-right:1rem}
}

/* === ACCESSIBILITY: REDUCED MOTION === */
@media(prefers-reduced-motion:reduce){
  *,*::before,*::after{transition-duration:0.01ms!important;animation-duration:0.01ms!important;animation-iteration-count:1!important;scroll-behavior:auto!important}
  .site-nav{transition:none!important}
  .nav-link:hover{transform:none!important}
  .card:hover{transform:none!important}
  .scroll-top{transition:opacity 0.2s,visibility 0.2s;transform:none!important}
  .scroll-top.visible{transform:none!important}
}

/* === IMAGE CONTAINER BASE === */
.img-container{position:relative;overflow:hidden;border-radius:var(--radius-md);background:var(--color-dark-gray)}
.img-container img{width:100%;height:100%;object-fit:cover;transition:var(--transition)}
.img-container:hover img{transform:scale(1.03)}
.img-ratio-16x9{padding-bottom:56.25%}
.img-ratio-4x3{padding-bottom:75%}
.img-ratio-1x1{padding-bottom:100%}
.img-placeholder{position:absolute;top:0;left:0;width:100%;height:100%;display:flex;align-items:center;justify-content:center;background:linear-gradient(135deg,var(--color-dark-gray),var(--color-primary-dark));color:rgba(255,255,255,0.2);font-size:0.9rem;letter-spacing:0.05em}

/* === RESPONSIVE: TABLET ONLY === */
@media(min-width:769px)and (max-width:1024px){
  .footer-grid{grid-template-columns:1fr 1fr;gap:2rem}
  .footer-brand{grid-column:1/3}
}