/* ===== RESET & BASE ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body { font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif; font-weight: 400; line-height: 1.6; color: #E8E6E1; background-color: #2C2A26; min-height: 100vh; -webkit-font-smoothing: antialiased; }
img, svg, video { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; transition: color 0.2s ease, border-color 0.2s ease; }
ul, ol { list-style: none; }
button { font: inherit; color: inherit; background: none; border: none; cursor: pointer; appearance: none; -webkit-appearance: none; }
:focus-visible { outline: 2px solid #FF6B35; outline-offset: 2px; border-radius: 2px; }

/* ===== CSS VARIABLES ===== */
:root {
  --clr-primary-deep-green: #1B4332;
  --clr-primary-dark-gold: #C9A959;
  --clr-accent-neon-orange: #FF6B35;
  --clr-bg-dark-rock: #2C2A26;
  --clr-surface-dark-green: #2D4A3E;
  --clr-text-off-white: #E8E6E1;
  --clr-text-muted-gold: #B89B5B;
  --clr-border-olive: #5C6B4A;
  --clr-chart-green: #2E7D5A;
  --clr-chart-orange: #E65525;
  --border-thick: 4px;
  --border-medium: 2px;
  --shadow-heavy: 0 8px 32px rgba(0,0,0,0.5);
  --shadow-medium: 0 4px 16px rgba(0,0,0,0.35);
  --font-heading: 'Inter', 'Noto Sans SC', sans-serif;
  --font-body: 'Inter', 'Noto Sans SC', sans-serif;
  --font-data: 'JetBrains Mono', 'Source Code Pro', monospace;
  --max-width: 1280px;
  --header-height: 72px;
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 40px;
  --space-2xl: 64px;
  --transition-fast: 0.2s ease;
  --transition-med: 0.35s ease;
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; }
  html { scroll-behavior: auto; }
}

/* ===== SKIP LINK ===== */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-md);
  z-index: 9999;
  padding: var(--space-sm) var(--space-md);
  background: var(--clr-accent-neon-orange);
  color: #fff;
  font-weight: 700;
  font-size: 0.875rem;
  border-radius: 0 0 4px 4px;
  transition: top 0.25s ease;
}
.skip-link:focus { top: 0; }

/* ===== SITE HEADER ===== */
.site-header {
  position: relative;
  z-index: 100;
  background-color: var(--clr-primary-deep-green);
  border-top: var(--border-thick) solid var(--clr-primary-dark-gold);
  box-shadow: var(--shadow-heavy);
}
/* 左侧刻度装饰 */
.site-header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 12px;
  height: 100%;
  background: repeating-linear-gradient(
    to bottom,
    var(--clr-primary-dark-gold) 0px,
    var(--clr-primary-dark-gold) 1px,
    transparent 1px,
    transparent 8px
  );
  opacity: 0.35;
  pointer-events: none;
}
.header-frame {
  position: relative;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-lg);
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
}
/* 左上角索引菱形 */
.header-corner {
  position: absolute;
  top: calc(-1 * var(--border-thick) - 2px);
  left: var(--space-lg);
  font-size: 0.75rem;
  color: var(--clr-primary-dark-gold);
  letter-spacing: 0.1em;
  opacity: 0.7;
  font-weight: 300;
  transform: translateY(-50%);
}
/* 品牌 */
.header-brand { flex-shrink: 0; }
.brand-link {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  color: var(--clr-text-off-white);
  transition: opacity var(--transition-fast);
}
.brand-link:hover { opacity: 0.85; }
.brand-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  font-size: 0.8rem;
  color: var(--clr-primary-dark-gold);
  background: var(--clr-primary-deep-green);
  border: 1px solid var(--clr-primary-dark-gold);
  transform: rotate(45deg);
  flex-shrink: 0;
}
.brand-icon::before { content: '◆'; transform: rotate(-45deg); display: block; }
.brand-text {
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: -0.02em;
  line-height: 1.2;
  display: flex;
  align-items: baseline;
  gap: 0.3em;
}
.brand-tagline {
  font-weight: 300;
  font-size: 0.7rem;
  color: var(--clr-text-muted-gold);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  opacity: 0.8;
}
/* 导航 */
.header-nav { display: flex; align-items: center; }
.nav-list {
  display: flex;
  gap: var(--space-xs);
  align-items: center;
}
.nav-link {
  display: inline-block;
  padding: var(--space-sm) var(--space-md);
  font-family: var(--font-heading);
  font-weight: 500;
  font-size: 0.85rem;
  letter-spacing: 0.03em;
  color: var(--clr-text-off-white);
  border-bottom: 2px solid transparent;
  transition: color var(--transition-fast), border-color var(--transition-fast), background var(--transition-fast);
  position: relative;
  white-space: nowrap;
}
.nav-link:hover { color: var(--clr-primary-dark-gold); border-bottom-color: var(--clr-primary-dark-gold); }
.nav-link[aria-current="page"] {
  color: var(--clr-accent-neon-orange);
  border-bottom-color: var(--clr-accent-neon-orange);
  font-weight: 700;
}
.nav-link[aria-current="page"]::after {
  content: '◆';
  position: absolute;
  bottom: -6px;
  left: 50%;
  transform: translateX(-50%) scale(0.5);
  font-size: 0.6rem;
  color: var(--clr-accent-neon-orange);
  opacity: 0.9;
}
/* 汉堡按钮 */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  gap: 5px;
  background: transparent;
  border: 1px solid var(--clr-border-olive);
  border-radius: 2px;
  transition: border-color var(--transition-fast);
}
.nav-toggle:hover { border-color: var(--clr-primary-dark-gold); }
.toggle-bar {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--clr-text-off-white);
  transition: transform var(--transition-med), opacity var(--transition-med);
  border-radius: 1px;
}
/* 移动端 */
@media (max-width: 820px) {
  .header-frame { padding: 0 var(--space-md); }
  .header-corner { left: var(--space-md); }
  .nav-toggle { display: flex; }
  .header-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--clr-primary-deep-green);
    border-top: 2px solid var(--clr-primary-dark-gold);
    box-shadow: var(--shadow-heavy);
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-med), padding var(--transition-med);
    padding: 0 var(--space-md);
  }
  .header-nav[data-open] {
    max-height: 480px;
    padding: var(--space-md);
  }
  .nav-list {
    flex-direction: column;
    gap: var(--space-sm);
    width: 100%;
  }
  .nav-link {
    display: block;
    width: 100%;
    padding: var(--space-sm) var(--space-md);
    border-bottom: 1px solid rgba(201,169,89,0.2);
    border-left: 3px solid transparent;
  }
  .nav-link:hover { border-left-color: var(--clr-primary-dark-gold); background: rgba(201,169,89,0.08); }
  .nav-link[aria-current="page"] {
    border-left-color: var(--clr-accent-neon-orange);
    background: rgba(255,107,53,0.08);
    border-bottom-color: transparent;
  }
  .nav-link[aria-current="page"]::after { display: none; }
}
@media (max-width: 480px) {
  :root { --header-height: 60px; }
  .brand-text { font-size: 0.9rem; }
  .brand-tagline { font-size: 0.6rem; }
  .brand-icon { width: 24px; height: 24px; font-size: 0.7rem; }
  .header-frame { padding: 0 var(--space-sm); }
  .header-corner { left: var(--space-sm); font-size: 0.6rem; }
}

/* ===== SITE FOOTER ===== */
.site-footer {
  background-color: var(--clr-bg-dark-rock);
  border-top: var(--border-thick) solid var(--clr-primary-dark-gold);
  padding: var(--space-2xl) 0 var(--space-lg);
  margin-top: auto;
}
.footer-frame {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1.2fr;
  gap: var(--space-xl);
  margin-bottom: var(--space-xl);
}
.footer-col-title {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 0.85rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--clr-primary-dark-gold);
  margin-bottom: var(--space-md);
  border-bottom: 1px solid rgba(201,169,89,0.25);
  padding-bottom: var(--space-sm);
}
/* 品牌列 */
.footer-brand-heading {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
}
.footer-brand-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  color: var(--clr-primary-dark-gold);
  border: 1px solid var(--clr-primary-dark-gold);
  transform: rotate(45deg);
  font-size: 0.55rem;
  flex-shrink: 0;
}
.footer-brand-icon::before { content: '◆'; transform: rotate(-45deg); display: block; }
.footer-brand-name {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1rem;
  color: var(--clr-text-off-white);
  letter-spacing: -0.01em;
}
.footer-brand-desc {
  font-size: 0.85rem;
  color: var(--clr-text-muted-gold);
  line-height: 1.7;
  margin-bottom: var(--space-md);
  max-width: 32em;
}
.trust-statement {
  font-size: 0.75rem;
  font-style: italic;
  color: rgba(184,155,91,0.6);
  line-height: 1.5;
  border-left: 2px solid var(--clr-primary-dark-gold);
  padding-left: var(--space-sm);
}
/* 导航列 */
.footer-nav-list { display: flex; flex-direction: column; gap: var(--space-sm); }
.footer-nav-list a { font-size: 0.85rem; color: var(--clr-text-off-white); transition: color var(--transition-fast); }
.footer-nav-list a:hover { color: var(--clr-accent-neon-orange); }
/* 联系列 */
.footer-contact-list { display: flex; flex-direction: column; gap: var(--space-sm); font-size: 0.85rem; color: var(--clr-text-off-white); }
.footer-contact-list a { color: var(--clr-primary-dark-gold); transition: color var(--transition-fast); }
.footer-contact-list a:hover { color: var(--clr-accent-neon-orange); }
.footer-contact-note { font-size: 0.75rem; color: var(--clr-text-muted-gold); font-style: italic; margin-top: var(--space-sm); }
/* 分割线 */
.footer-divider {
  height: 1px;
  background: linear-gradient(to right, var(--clr-primary-dark-gold), transparent);
  opacity: 0.3;
  margin-bottom: var(--space-lg);
}
/* 底部 */
.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-sm);
  font-size: 0.75rem;
  color: var(--clr-text-muted-gold);
}
.footer-icp { letter-spacing: 0.05em; }
.footer-copyright { opacity: 0.8; }
@media (max-width: 820px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-col-brand { grid-column: 1 / -1; }
  .footer-frame { padding: 0 var(--space-md); }
}
@media (max-width: 480px) {
  .footer-grid { grid-template-columns: 1fr; gap: var(--space-lg); }
  .footer-bottom { flex-direction: column; align-items: flex-start; gap: var(--space-xs); }
  .footer-frame { padding: 0 var(--space-sm); }
  .site-footer { padding: var(--space-xl) 0 var(--space-md); }
}

/* ===== GENERIC UTILITY ===== */
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 var(--space-lg); }
@media (max-width: 480px) { .container { padding: 0 var(--space-sm); } }

/* ===== BUTTON ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-lg);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.85rem;
  letter-spacing: 0.03em;
  border: var(--border-medium) solid var(--clr-primary-dark-gold);
  background: transparent;
  color: var(--clr-primary-dark-gold);
  transition: background var(--transition-fast), color var(--transition-fast), box-shadow var(--transition-fast);
  cursor: pointer;
  text-transform: uppercase;
}
.btn:hover { background: var(--clr-primary-dark-gold); color: #1B4332; box-shadow: var(--shadow-medium); }
.btn:focus-visible { outline: 2px solid var(--clr-accent-neon-orange); outline-offset: 2px; }
.btn-primary { background: var(--clr-primary-dark-gold); color: #1B4332; border-color: var(--clr-primary-dark-gold); }
.btn-primary:hover { background: transparent; color: var(--clr-primary-dark-gold); }
.btn-accent { border-color: var(--clr-accent-neon-orange); color: var(--clr-accent-neon-orange); }
.btn-accent:hover { background: var(--clr-accent-neon-orange); color: #fff; }

/* ===== BREADCRUMB ===== */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs) var(--space-sm);
  padding: var(--space-md) 0;
  font-size: 0.8rem;
  color: var(--clr-text-muted-gold);
}
.breadcrumb a { color: var(--clr-text-muted-gold); transition: color var(--transition-fast); }
.breadcrumb a:hover { color: var(--clr-primary-dark-gold); }
.breadcrumb .separator { color: rgba(184,155,91,0.4); user-select: none; }
.breadcrumb [aria-current="page"] { color: var(--clr-text-off-white); font-weight: 500; }

/* ===== CONTENT CONTAINER ===== */
.content-section {
  padding: var(--space-2xl) 0;
}
.content-section + .content-section { border-top: 1px solid rgba(201,169,89,0.15); }

/* ===== GRID ===== */
.grid { display: grid; gap: var(--space-lg); }
.grid-2 { grid-template-columns: 1fr 1fr; }
.grid-3 { grid-template-columns: 1fr 1fr 1fr; }
@media (max-width: 820px) { .grid-2, .grid-3 { grid-template-columns: 1fr; } }

/* ===== CARD ===== */
.card {
  background: var(--clr-surface-dark-green);
  border: var(--border-medium) solid var(--clr-border-olive);
  box-shadow: var(--shadow-heavy);
  padding: var(--space-lg);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}
.card:hover { border-color: var(--clr-primary-dark-gold); box-shadow: var(--shadow-heavy), 0 0 0 1px rgba(201,169,89,0.1); }
.card-title { font-family: var(--font-heading); font-weight: 700; font-size: 1.1rem; color: var(--clr-text-off-white); margin-bottom: var(--space-sm); }
.card-text { font-size: 0.9rem; color: var(--clr-text-muted-gold); line-height: 1.7; }

/* ===== PAGE HEADING ===== */
.page-heading {
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 2.2rem;
  letter-spacing: -0.03em;
  color: var(--clr-text-off-white);
  line-height: 1.15;
  margin-bottom: var(--space-md);
  position: relative;
  display: inline-block;
}
.page-heading::after {
  content: '';
  display: block;
  width: 60px;
  height: var(--border-thick);
  background: var(--clr-primary-dark-gold);
  margin-top: var(--space-sm);
}
.page-subheading {
  font-size: 1rem;
  color: var(--clr-text-muted-gold);
  font-weight: 300;
  max-width: 32em;
  margin-bottom: var(--space-lg);
}
@media (max-width: 480px) {
  .page-heading { font-size: 1.6rem; }
}

/* ===== DATA DISPLAY ===== */
.data-number {
  font-family: var(--font-data);
  font-weight: 500;
  font-size: 1.4rem;
  color: var(--clr-accent-neon-orange);
  letter-spacing: -0.02em;
}
.data-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--clr-text-muted-gold);
}

/* ===== SCROLL PROGRESS (JS) ===== */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 3px;
  background: linear-gradient(90deg, var(--clr-primary-dark-gold), var(--clr-accent-neon-orange));
  z-index: 999;
  transition: width 0.1s linear;
  pointer-events: none;
}
@media (prefers-reduced-motion: reduce) {
  .scroll-progress { display: none; }
}

/* ===== VISIBILITY ===== */
.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; }