/* ===== Reset & Base ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  background: #F5F5F0;
  color: #1A1A1A;
  line-height: 1.6;
  overflow-x: hidden;
}
ul, ol { list-style: none; }
a { color: inherit; text-decoration: none; }
img, svg { display: block; max-width: 100%; }
button { font: inherit; cursor: pointer; border: none; background: none; }
:focus-visible {
  outline: 3px solid #E67E22;
  outline-offset: 2px;
}
::selection { background: #C9A227; color: #0B3B2D; }

/* ===== CSS Variables ===== */
:root {
  --primary: #0B3B2D;
  --primary-dark: #072A20;
  --primary-light: #1F5A44;
  --gold: #C9A227;
  --orange: #E67E22;
  --dark: #1A1A1A;
  --light: #F5F5F0;
  --white: #FFFFFF;
  --glass: rgba(255, 255, 255, 0.08);
  --glass-border: rgba(255, 255, 255, 0.18);
  --max: 1200px;
  --radius: 4px;
  --shadow: 0 12px 40px rgba(0, 0, 0, 0.14);
  --font-data: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
}
.container {
  width: min(100% - 48px, var(--max));
  margin-inline: auto;
}
.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;
}

/* ===== Skip Link ===== */
.skip-link {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 3000;
  background: var(--orange);
  color: var(--white);
  padding: 10px 20px;
  border-radius: var(--radius);
  font-weight: 700;
  transform: translateY(-80px);
  transition: transform 0.2s ease;
}
.skip-link:focus {
  transform: translateY(0);
}

/* ===== Scroll Progress ===== */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0;
  background: linear-gradient(90deg, var(--gold), var(--orange));
  z-index: 2500;
  pointer-events: none;
}

/* ===== Site Header ===== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: transparent;
  border-bottom: 1px solid transparent;
  transition: background 0.35s ease, border-color 0.35s ease, box-shadow 0.35s ease;
}
.site-header[data-scrolled] {
  background: rgba(7, 42, 32, 0.96);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom-color: rgba(201, 162, 39, 0.4);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.25);
}
.header-inner {
  display: flex;
  align-items: center;
  gap: 24px;
  min-height: 80px;
}
.nav-brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
}
.brand-mark {
  width: 40px;
  height: 40px;
  flex: 0 0 auto;
}
.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}
.brand-text strong {
  font-size: 1.15rem;
  font-weight: 900;
  color: var(--white);
  letter-spacing: 0.04em;
}
.brand-text small {
  font-size: 0.7rem;
  color: rgba(255, 255, 255, 0.68);
  letter-spacing: 0.06em;
  margin-top: 3px;
}
.site-header[data-scrolled] .brand-text strong { color: var(--white); }
.nav-links {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-inline-start: auto;
}
.nav-links a {
  position: relative;
  color: rgba(255, 255, 255, 0.9);
  font-size: 0.92rem;
  font-weight: 600;
  padding: 10px 12px 8px;
  transition: color 0.2s;
}
.nav-links a::after {
  content: "";
  position: absolute;
  left: 12px;
  right: 12px;
  bottom: 2px;
  height: 2px;
  background: var(--gold);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.25s ease;
}
.nav-links a:hover { color: var(--gold); }
.nav-links a:hover::after { transform: scaleX(1); }
.nav-links a[aria-current="page"] {
  color: var(--gold);
}
.nav-links a[aria-current="page"]::after {
  transform: scaleX(1);
}
.nav-cta {
  flex: 0 0 auto;
  margin-inline-start: 8px;
}

/* Nav Toggle */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 6px;
  width: 44px;
  height: 44px;
  padding: 8px;
}
.nav-toggle-line {
  display: block;
  height: 2px;
  width: 24px;
  background: var(--white);
  transition: transform 0.25s ease, opacity 0.25s ease;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(1) { transform: translateY(8px) 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(-8px) rotate(-45deg); }

/* Mobile Nav */
.mobile-nav {
  display: none;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-weight: 700;
  font-size: 0.9rem;
  line-height: 1;
  padding: 13px 22px;
  border-radius: 2px;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease, transform 0.15s ease;
  letter-spacing: 0.02em;
}
.btn:active { transform: translateY(1px); }
.btn-primary {
  background: var(--primary);
  color: var(--white);
  border: 1px solid var(--primary);
  box-shadow: 0 4px 14px rgba(11, 59, 45, 0.3);
}
.btn-primary:hover {
  background: var(--primary-light);
  border-color: var(--primary-light);
}
.btn-outline {
  background: transparent;
  color: var(--gold);
  border: 1px solid var(--gold);
}
.btn-outline:hover {
  background: var(--gold);
  color: var(--primary-dark);
}

/* ===== Breadcrumb ===== */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  align-items: center;
  font-size: 0.82rem;
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: 24px;
}
.breadcrumb a:hover { color: var(--gold); }
.breadcrumb [aria-current="page"] { color: var(--gold); font-weight: 700; }
.breadcrumb li + li::before {
  content: "/";
  margin-inline: 6px;
  color: rgba(255, 255, 255, 0.35);
}

/* ===== Section ===== */
.section { padding: 90px 0; }
.section-dark {
  background: var(--primary);
  color: var(--white);
}
.section-dark .section-title { color: var(--white); }
.section-light {
  background: var(--light);
  color: var(--dark);
}
.section-white {
  background: var(--white);
  color: var(--dark);
}
.section-head {
  margin-bottom: 48px;
  position: relative;
  display: flex;
  align-items: flex-start;
  gap: 18px;
}
.eyebrow {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.22em;
  color: var(--gold);
  font-weight: 800;
}
.section-title {
  font-size: clamp(1.6rem, 4vw, 2.6rem);
  font-weight: 900;
  line-height: 1.2;
  color: var(--primary);
}
.section-note {
  writing-mode: vertical-rl;
  font-size: 0.78rem;
  color: rgba(255, 255, 255, 0.55);
  border-inline-start: 1px solid rgba(201, 162, 39, 0.5);
  padding-inline-start: 10px;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  align-self: stretch;
}
.section-light .section-note { color: rgba(11, 59, 45, 0.5); border-color: rgba(11, 59, 45, 0.2); }
.section-white .section-note { color: rgba(11, 59, 45, 0.5); border-color: rgba(11, 59, 45, 0.2); }

/* ===== Card Grid ===== */
.grid-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.card {
  background: var(--white);
  border-radius: 6px;
  border-top: 3px solid var(--gold);
  padding: 28px 24px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
  transition: transform 0.2s ease, box-shadow 0.25s ease;
  display: flex;
  flex-direction: column;
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}
.card-index {
  font-family: var(--font-data);
  font-size: 0.85rem;
  color: var(--gold);
  font-weight: 700;
  letter-spacing: 0.08em;
}
.card-title {
  font-size: 1.15rem;
  font-weight: 900;
  color: var(--primary);
  margin: 14px 0 8px;
}
.card-desc {
  font-size: 0.9rem;
  color: rgba(26, 26, 26, 0.72);
  flex: 1;
  margin-bottom: 16px;
}
.card-meta {
  font-size: 0.82rem;
  color: rgba(26, 26, 26, 0.5);
  border-top: 1px solid rgba(11, 59, 45, 0.12);
  padding-top: 12px;
}

/* Dark card variant */
.card-inverse {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--glass-border);
  border-top-color: var(--gold);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
}
.card-inverse .card-title { color: var(--white); }
.card-inverse .card-desc { color: rgba(255, 255, 255, 0.72); }
.card-inverse .card-meta { color: rgba(255, 255, 255, 0.5); border-color: rgba(255, 255, 255, 0.14); }

/* ===== Tags ===== */
.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.tag {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 700;
  padding: 8px 14px;
  border-radius: 99px;
  background: rgba(201, 162, 39, 0.1);
  border: 1px solid rgba(201, 162, 39, 0.4);
  color: var(--primary);
  transition: background 0.2s, border-color 0.2s;
}
.tag:hover {
  background: rgba(201, 162, 39, 0.25);
  border-color: var(--gold);
}
.section-dark .tag {
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(201, 162, 39, 0.5);
  color: rgba(255, 255, 255, 0.85);
}
.section-dark .tag:hover {
  background: rgba(201, 162, 39, 0.2);
  color: var(--white);
}

/* ===== Buttons Group ===== */
.btn-group {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  align-items: center;
}

/* ===== Tabs ===== */
.tabs {
  margin-top: 8px;
}
.tabs-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.16);
  margin-bottom: 28px;
}
.tab-btn {
  padding: 12px 22px;
  font-size: 0.9rem;
  font-weight: 800;
  color: rgba(255, 255, 255, 0.65);
  border-bottom: 3px solid transparent;
  transition: color 0.2s, border-color 0.2s;
}
.tab-btn:hover { color: var(--white); }
.tab-btn[aria-selected="true"] {
  color: var(--gold);
  border-bottom-color: var(--gold);
}
.tab-panel {
  display: none;
}
.tab-panel[data-active] {
  display: block;
}
.section-light .tabs-nav { border-color: rgba(11, 59, 45, 0.18); }
.section-light .tab-btn { color: rgba(11, 59, 45, 0.6); }
.section-light .tab-btn:hover { color: var(--primary); }
.section-light .tab-btn[aria-selected="true"] { color: var(--primary); }

/* ===== Stat Grid ===== */
.stat-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.stat-item {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 4px;
  padding: 24px 20px;
  text-align: center;
}
.stat-item strong {
  display: block;
  font-family: var(--font-data);
  font-size: 2.1rem;
  color: var(--gold);
  font-weight: 800;
}
.stat-item span {
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.7);
  letter-spacing: 0.06em;
}

/* ===== Section Divider ===== */
.section-divider {
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(201, 162, 39, 0.6), transparent);
  position: relative;
  margin: 60px 0;
}
.section-divider::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 10px;
  height: 10px;
  background: var(--gold);
  transform: translate(-50%, -50%) rotate(45deg);
}
.section-dark .section-divider { background: linear-gradient(90deg, transparent, rgba(255,255,255,0.15), transparent); }
.section-dark .section-divider::after { background: var(--orange); }

/* ===== Article Index ===== */
.article-index {
  position: sticky;
  top: 120px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(201, 162, 39, 0.3);
  padding: 24px;
  border-radius: 4px;
}
.article-index h2 {
  font-size: 0.85rem;
  color: var(--gold);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 16px;
}
.article-index a {
  display: block;
  padding: 8px 0;
  color: rgba(255, 255, 255, 0.78);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 0.9rem;
  transition: color 0.2s, padding-left 0.2s;
}
.article-index a:hover {
  color: var(--gold);
  padding-left: 8px;
}

/* ===== Pagination ===== */
.pagination {
  display: flex;
  gap: 8px;
  margin-top: 40px;
  flex-wrap: wrap;
}
.pagination a, .pagination span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 40px;
  height: 40px;
  padding: 0 10px;
  border: 1px solid rgba(201, 162, 39, 0.5);
  color: var(--primary);
  font-size: 0.9rem;
  font-weight: 700;
  border-radius: 2px;
  transition: background 0.2s, color 0.2s;
}
.pagination a:hover {
  background: var(--gold);
  color: var(--primary-dark);
  border-color: var(--gold);
}
.pagination .current {
  background: var(--primary);
  color: var(--gold);
  border-color: var(--primary);
}

/* ===== Image Placeholder Base ===== */
.img-frame {
  position: relative;
  display: block;
  width: 100%;
  border-radius: 6px;
  overflow: hidden;
  background: var(--primary-dark);
  border: 1px solid rgba(201, 162, 39, 0.3);
}
.img-frame::before {
  content: "";
  display: block;
  padding-top: 62%;
}
.img-frame[data-ratio="wide"]::before { padding-top: 42%; }
.img-frame[data-ratio="square"]::before { padding-top: 100%; }
.img-frame[data-ratio="tall"]::before { padding-top: 130%; }
.img-frame .img-grid,
.img-frame .img-pitch,
.img-frame .img-data {
  position: absolute;
  inset: 0;
}
.img-frame .img-pitch {
  background:
    linear-gradient(rgba(255,255,255,0.08) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.08) 1px, transparent 1px);
  background-size: 20px 20px;
}
.img-frame .img-pitch::after {
  content: "";
  position: absolute;
  inset: 10%;
  border: 2px solid rgba(255,255,255,0.24);
  border-radius: 50%;
}
.img-frame .img-grid {
  background-image:
    radial-gradient(circle at 20% 30%, rgba(230,126,34,0.5) 1px, transparent 1.5px),
    radial-gradient(circle at 70% 80%, rgba(201,162,39,0.5) 1px, transparent 1.5px),
    radial-gradient(circle at 30% 70%, rgba(255,255,255,0.25) 1px, transparent 1.5px),
    linear-gradient(rgba(255,255,255,0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.05) 1px, transparent 1px);
  background-size: 40px 40px, 30px 30px, 26px 26px, 28px 28px, 28px 28px;
}
.img-frame .img-data {
  background:
    repeating-linear-gradient(0deg, rgba(201,162,39,0.28) 0 1px, transparent 1px 12px),
    linear-gradient(145deg, rgba(11,59,45,0.2), rgba(7,42,32,0.75));
}
.img-frame .img-data::after {
  content: "0 1 2 3 4 5 6";
  font-family: var(--font-data);
  font-size: 0.9rem;
  color: rgba(255,255,255,0.6);
  position: absolute;
  bottom: 12px;
  left: 16px;
  letter-spacing: 4px;
}
.img-caption {
  margin-top: 10px;
  font-size: 0.78rem;
  color: rgba(255, 255, 255, 0.6);
  display: flex;
  justify-content: space-between;
  gap: 12px;
}
.section-light .img-caption, .section-white .img-caption { color: rgba(11,59,45,0.6); }

/* ===== Back To Top ===== */
.back-to-top {
  position: fixed;
  bottom: 28px;
  right: 28px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--primary);
  border: 1px solid var(--gold);
  color: var(--gold);
  font-size: 1.4rem;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transform: translateY(16px);
  transition: opacity 0.25s, transform 0.25s, background 0.2s;
  z-index: 900;
}
.back-to-top[data-visible] {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}
.back-to-top:hover {
  background: var(--primary-light);
  color: var(--white);
}

/* ===== Footer ===== */
.site-footer {
  background: var(--primary-dark);
  color: rgba(255, 255, 255, 0.8);
  border-top: 4px solid var(--gold);
  padding-top: 64px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.3fr 1fr 1.1fr 1fr;
  gap: 44px;
  padding-bottom: 48px;
}
.footer-logo {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 18px;
}
.footer-logo strong {
  font-size: 1.2rem;
  font-weight: 900;
  color: var(--white);
}
.footer-brand p {
  font-size: 0.88rem;
  color: rgba(255,255,255,0.65);
  line-height: 1.7;
}
.site-footer h3 {
  font-size: 0.9rem;
  color: var(--gold);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  margin-bottom: 18px;
}
.footer-links ul {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 4px 18px;
}
.footer-links a, .footer-contact a {
  color: rgba(255, 255, 255, 0.72);
  font-size: 0.88rem;
  transition: color 0.2s, padding-left 0.2s;
}
.footer-links a:hover, .footer-contact a:hover {
  color: var(--gold);
  padding-left: 4px;
}
.footer-contact ul li {
  font-size: 0.87rem;
  padding: 5px 0;
  color: rgba(255,255,255,0.72);
  line-height: 1.6;
}
.footer-contact ul li:first-child {
  padding-top: 0;
}
.footer-contact a {
  padding-left: 0;
}
.footer-contact a:hover {
  padding-left: 0;
  color: var(--gold);
}
.footer-aside p {
  font-size: 0.86rem;
  color: rgba(255,255,255,0.68);
  line-height: 1.7;
  margin-bottom: 20px;
  background: rgba(230, 126, 34, 0.08);
  border-left: 3px solid var(--orange);
  padding: 14px;
}
.footer-btn {
  font-size: 0.82rem;
  padding: 10px 18px;
}
.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: 18px 0;
  background: var(--primary);
}
.footer-bottom-inner {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
.footer-bottom p {
  font-size: 0.78rem;
  color: rgba(255, 255, 255, 0.55);
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  .grid-cards {
    grid-template-columns: repeat(2, 1fr);
  }
  .stat-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .nav-cta { display: none; }
  .nav-toggle { display: flex; }
  .nav-links { display: none; }
  .mobile-nav {
    display: block;
    position: absolute;
    top: 80px;
    left: 0;
    width: 100%;
    background: rgba(7, 42, 32, 0.98);
    border-bottom: 3px solid var(--gold);
    padding: 24px 24px 32px;
    transform: translateY(-12px);
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.25s ease, transform 0.25s ease, visibility 0.25s;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
  }
  .mobile-nav[data-open] {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }
  .mobile-nav-links {
    display: grid;
    gap: 4px;
  }
  .mobile-nav-links a {
    display: block;
    padding: 13px 8px;
    font-size: 1.02rem;
    font-weight: 700;
    color: rgba(255,255,255,0.85);
    border-bottom: 1px solid rgba(255,255,255,0.1);
    transition: color 0.2s, border-color 0.2s;
  }
  .mobile-nav-links a:hover {
    color: var(--gold);
    border-color: rgba(201,162,39,0.4);
  }
  .mobile-nav-links a[aria-current="page"] {
    color: var(--gold);
    border-bottom-color: var(--gold);
  }
  .mobile-nav-cta {
    margin-top: 22px;
    width: 100%;
  }
  .mobile-nav-note {
    margin-top: 18px;
    font-size: 0.78rem;
    color: rgba(255,255,255,0.55);
    line-height: 1.7;
  }
}

@media (max-width: 640px) {
  .section { padding: 64px 0; }
  .container { width: min(100% - 32px, var(--max)); }
  .header-inner { min-height: 68px; }
  .mobile-nav { top: 68px; }
  .brand-mark { width: 34px; height: 34px; }
  .brand-text strong { font-size: 1rem; }
  .brand-text small { font-size: 0.62rem; }
  .nav-toggle-line { width: 20px; }
  .grid-cards { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 36px; }
  .footer-links ul { grid-template-columns: 1fr 1fr; }
  .footer-bottom-inner { flex-direction: column; text-align: center; }
  .stat-grid { grid-template-columns: 1fr 1fr; }
  .btn { width: 100%; }
  .btn-group .btn { width: auto; }
  .section-head { flex-wrap: wrap; }
  .back-to-top { bottom: 20px; right: 20px; width: 42px; height: 42px; }
}

/* ===== Reduced Motion ===== */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  .card:hover { transform: none; }
  .back-to-top { transition: opacity 0.01ms, transform 0.01ms; }
}

/* ===== Print ===== */
@media print {
  .site-header, .site-footer, .back-to-top, .scroll-progress { display: none !important; }
  body { background: #fff; color: #000; }
  .section { padding: 30px 0; }
}