/* ===== Reset & Base ===== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}
body {
  margin: 0;
  font-family: 'Noto Serif SC', 'Source Han Serif SC', 'Songti SC', SimSun, Georgia, 'Times New Roman', serif;
  font-weight: 400;
  font-size: 16px;
  line-height: 1.7;
  color: #1C1C1E;
  background-color: #F5F0E8;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
img,
svg {
  display: block;
  max-width: 100%;
  height: auto;
}
a {
  color: inherit;
  text-decoration: none;
  transition: color 0.25s ease;
}
ul, ol {
  list-style: none;
}
button {
  font: inherit;
  cursor: pointer;
  border: none;
  background: none;
  color: inherit;
}
:focus-visible {
  outline: 2px solid #D4AF37;
  outline-offset: 2px;
  border-radius: 2px;
}
/* ===== CSS Variables ===== */
:root {
  --color-primary-dark: #0A2B4E;
  --color-primary-medium: #1A5276;
  --color-primary-light: #2980B9;
  --color-accent-gold: #D4AF37;
  --color-accent-gold-light: #F1C40F;
  --color-highlight-red: #E74C3C;
  --color-background-cream: #F5F0E8;
  --color-text-dark: #1C1C1E;
  --color-text-light: #FFFFFF;
  --color-border-light: rgba(10, 43, 78, 0.12);
  --color-border-gold: rgba(212, 175, 55, 0.4);
  --font-heading: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Helvetica Neue', Arial, sans-serif;
  --font-body: 'Noto Serif SC', 'Source Han Serif SC', 'Songti SC', SimSun, Georgia, 'Times New Roman', serif;
  --container-max: 1280px;
  --header-height: 64px;
  --transition-standard: 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
  --shadow-card: 0 1px 3px rgba(10, 43, 78, 0.08);
  --radius-none: 0px;
}
/* ===== Skip Link ===== */
.skip-link {
  position: absolute;
  top: -100%;
  left: 0;
  z-index: 10000;
  padding: 12px 24px;
  background: var(--color-primary-dark);
  color: var(--color-text-light);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 14px;
  transition: top 0.25s ease;
}
.skip-link:focus {
  top: 0;
  outline: 2px solid var(--color-accent-gold);
  outline-offset: 2px;
}
/* ===== Scroll Progress ===== */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  z-index: 9999;
  background: transparent;
  pointer-events: none;
}
.scroll-progress::after {
  content: '';
  display: block;
  width: 0%;
  height: 100%;
  background: linear-gradient(90deg, var(--color-accent-gold), var(--color-accent-gold-light));
  transition: width 0.1s linear;
  will-change: width;
}
.scroll-progress[data-progress]::after {
  width: calc(var(--data-progress, 0) * 1%);
}
@media (prefers-reduced-motion: reduce) {
  .scroll-progress::after {
    transition: none;
  }
}
/* ===== Header ===== */
.site-header {
  position: fixed;
  top: 3px;
  left: 0;
  width: 100%;
  height: var(--header-height);
  z-index: 9000;
  background: transparent;
  transition: background 0.35s ease, box-shadow 0.35s ease;
}
.site-header[data-scrolled] {
  background: var(--color-primary-dark);
  box-shadow: 0 2px 12px rgba(10, 43, 78, 0.25);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
}
/* Brand */
.brand-link {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--color-text-light);
  transition: opacity 0.25s ease;
}
.brand-link:hover {
  opacity: 0.85;
}
.brand-name {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 22px;
  letter-spacing: 1px;
  color: var(--color-accent-gold);
  text-shadow: 0 1px 2px rgba(0,0,0,0.15);
}
.brand-graphic {
  color: var(--color-accent-gold-light);
  opacity: 0.9;
}
.site-header[data-scrolled] .brand-graphic {
  color: var(--color-accent-gold);
}
/* Navigation */
.main-nav {
  display: flex;
  align-items: center;
}
.nav-list {
  display: flex;
  gap: 6px;
}
.nav-link {
  display: block;
  padding: 8px 16px;
  font-family: var(--font-heading);
  font-weight: 500;
  font-size: 14px;
  letter-spacing: 0.3px;
  color: var(--color-text-light);
  border-radius: var(--radius-none);
  transition: background 0.25s ease, color 0.25s ease;
  position: relative;
}
.nav-link::after {
  content: '';
  position: absolute;
  bottom: 2px;
  left: 16px;
  right: 16px;
  height: 2px;
  background: var(--color-accent-gold);
  transform: scaleX(0);
  transform-origin: center;
  transition: transform 0.3s ease;
}
.nav-link:hover::after,
.nav-link[aria-current="page"]::after {
  transform: scaleX(1);
}
.nav-link[aria-current="page"] {
  color: var(--color-accent-gold);
  font-weight: 700;
}
.nav-link:hover {
  background: rgba(255,255,255,0.08);
  color: var(--color-accent-gold-light);
}
.site-header[data-scrolled] .nav-link:hover {
  background: rgba(212,175,55,0.12);
}
/* Nav Toggle (mobile) */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 44px;
  height: 44px;
  gap: 5px;
  padding: 8px;
  background: transparent;
  border-radius: var(--radius-none);
  transition: background 0.25s ease;
}
.nav-toggle:hover {
  background: rgba(255,255,255,0.1);
}
.nav-toggle-icon {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text-light);
  border-radius: 1px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-icon:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-icon:nth-child(2) {
  opacity: 0;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-icon:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}
/* ===== Footer ===== */
.site-footer {
  background: var(--color-primary-dark);
  color: var(--color-text-light);
  padding: 48px 0 32px;
  border-top: 3px solid var(--color-accent-gold);
}
.footer-inner {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 40px;
}
.footer-heading {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 16px;
  color: var(--color-accent-gold);
  margin-bottom: 16px;
  letter-spacing: 0.5px;
}
.footer-link-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.footer-link {
  font-family: var(--font-body);
  font-size: 14px;
  color: rgba(255,255,255,0.8);
  transition: color 0.25s ease;
}
.footer-link:hover {
  color: var(--color-accent-gold-light);
}
.footer-contact-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.footer-contact-item {
  font-size: 14px;
  line-height: 1.6;
  color: rgba(255,255,255,0.8);
}
.contact-label {
  font-family: var(--font-heading);
  font-weight: 500;
  color: rgba(255,255,255,0.6);
}
.contact-text {
  color: rgba(255,255,255,0.8);
}
.footer-trust {
  font-size: 13px;
  line-height: 1.7;
  color: rgba(255,255,255,0.65);
  margin-top: 16px;
  max-width: 320px;
}
.footer-icp {
  margin-bottom: 8px;
}
.footer-icp .footer-link {
  font-size: 13px;
  color: rgba(255,255,255,0.6);
}
.footer-copyright {
  font-size: 13px;
  color: rgba(255,255,255,0.5);
  margin-top: 4px;
}
.footer-brand .brand-name {
  font-size: 20px;
}
.footer-brand .brand-graphic {
  width: 24px;
  height: 24px;
}
/* ===== Container ===== */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}
/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 14px;
  letter-spacing: 0.5px;
  border: 2px solid transparent;
  border-radius: var(--radius-none);
  transition: background 0.3s ease, color 0.3s ease, border-color 0.3s ease, transform 0.2s ease;
  cursor: pointer;
}
.btn:active {
  transform: scale(0.97);
}
.btn-primary {
  background: var(--color-primary-dark);
  color: var(--color-text-light);
  border-color: var(--color-primary-dark);
}
.btn-primary:hover {
  background: var(--color-accent-gold);
  border-color: var(--color-accent-gold);
  color: var(--color-primary-dark);
}
.btn-outline {
  background: transparent;
  color: var(--color-primary-dark);
  border-color: var(--color-primary-dark);
}
.btn-outline:hover {
  background: var(--color-primary-dark);
  color: var(--color-text-light);
}
.btn-gold {
  background: var(--color-accent-gold);
  color: var(--color-primary-dark);
  border-color: var(--color-accent-gold);
}
.btn-gold:hover {
  background: var(--color-accent-gold-light);
  border-color: var(--color-accent-gold-light);
}
/* ===== Grid ===== */
.grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.grid-item {
  min-width: 0;
}
/* ===== Card ===== */
.card {
  background: var(--color-background-cream);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-none);
  padding: 24px;
  box-shadow: var(--shadow-card);
  transition: box-shadow 0.3s ease, transform 0.3s ease;
}
.card:hover {
  box-shadow: 0 4px 16px rgba(10, 43, 78, 0.12);
  transform: translateY(-2px);
}
.card-gold {
  border-color: var(--color-border-gold);
  border-left: 4px solid var(--color-accent-gold);
}
/* ===== Visual Focus ===== */
.visual-focus {
  position: relative;
  padding: 32px 0;
  margin-bottom: 32px;
}
.visual-focus::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 60px;
  height: 4px;
  background: var(--color-accent-gold);
}
.visual-focus h1,
.visual-focus .focus-title {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 42px;
  line-height: 1.2;
  color: var(--color-primary-dark);
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}
.visual-focus .focus-sub {
  font-family: var(--font-body);
  font-size: 18px;
  color: var(--color-primary-medium);
  max-width: 640px;
  line-height: 1.6;
}
/* ===== Data Badge ===== */
.data-badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 14px;
  background: var(--color-accent-gold);
  color: var(--color-primary-dark);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 13px;
  letter-spacing: 0.3px;
  border-radius: var(--radius-none);
}
.data-badge-red {
  background: var(--color-highlight-red);
  color: var(--color-text-light);
}
.data-badge-outline {
  background: transparent;
  border: 1px solid var(--color-accent-gold);
  color: var(--color-accent-gold);
}
/* ===== Tag ===== */
.tag {
  display: inline-block;
  padding: 2px 12px;
  font-family: var(--font-heading);
  font-weight: 500;
  font-size: 12px;
  letter-spacing: 0.3px;
  border: 1px solid var(--color-border-light);
  color: var(--color-primary-medium);
  background: transparent;
  border-radius: var(--radius-none);
}
.tag-gold {
  border-color: var(--color-border-gold);
  color: var(--color-accent-gold);
}
/* ===== Divider ===== */
.divider {
  width: 100%;
  height: 1px;
  background: var(--color-border-light);
  margin: 24px 0;
}
.divider-gold {
  height: 2px;
  background: var(--color-accent-gold);
  opacity: 0.5;
}
/* ===== Breadcrumb ===== */
.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  padding: 16px 0;
  font-family: var(--font-heading);
  font-size: 13px;
  color: var(--color-primary-medium);
}
.breadcrumb a {
  color: var(--color-primary-light);
  transition: color 0.25s ease;
}
.breadcrumb a:hover {
  color: var(--color-accent-gold);
}
.breadcrumb-sep {
  color: var(--color-accent-gold);
  margin: 0 4px;
}
.breadcrumb-current {
  color: var(--color-text-dark);
  font-weight: 600;
}
/* ===== Content Section ===== */
.content-section {
  padding: 48px 0;
}
.content-section-light {
  background: var(--color-background-cream);
}
.content-section-dark {
  background: var(--color-primary-dark);
  color: var(--color-text-light);
}
/* ===== Image Container (placeholder) ===== */
.image-container {
  position: relative;
  width: 100%;
  padding-bottom: 66.67%;
  background: rgba(10, 43, 78, 0.06);
  border: 1px solid var(--color-border-light);
  overflow: hidden;
}
.image-container::after {
  content: '图表占位';
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-heading);
  font-size: 14px;
  color: var(--color-primary-medium);
  opacity: 0.4;
  letter-spacing: 0.5px;
}
.image-container img,
.image-container svg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
/* ===== Back to Top ===== */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 48px;
  height: 48px;
  background: var(--color-primary-dark);
  color: var(--color-accent-gold);
  border: 2px solid var(--color-accent-gold);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity 0.35s ease, visibility 0.35s ease, transform 0.35s ease, background 0.25s ease;
  z-index: 8000;
  border-radius: var(--radius-none);
}
.back-to-top[data-top] {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.back-to-top:hover {
  background: var(--color-accent-gold);
  color: var(--color-primary-dark);
}
.back-to-top svg {
  width: 22px;
  height: 22px;
}
/* ===== Accordion (shared) ===== */
.accordion {
  border-top: 1px solid var(--color-border-light);
}
.accordion-item {
  border-bottom: 1px solid var(--color-border-light);
}
.accordion-trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 16px 0;
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 16px;
  color: var(--color-primary-dark);
  background: transparent;
  text-align: left;
  cursor: pointer;
  transition: color 0.25s ease;
}
.accordion-trigger:hover {
  color: var(--color-accent-gold);
}
.accordion-icon {
  width: 20px;
  height: 20px;
  transition: transform 0.3s ease;
  color: var(--color-accent-gold);
}
.accordion-trigger[aria-expanded="true"] .accordion-icon {
  transform: rotate(45deg);
}
.accordion-content {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.4s ease;
}
.accordion-content > div {
  overflow: hidden;
}
.accordion-trigger[aria-expanded="true"] + .accordion-content {
  grid-template-rows: 1fr;
}
.accordion-panel {
  padding: 0 0 20px 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--color-primary-medium);
}
@media (prefers-reduced-motion: reduce) {
  .accordion-content {
    transition: none;
  }
  .accordion-icon {
    transition: none;
  }
}
/* ===== Table (shared) ===== */
.table-wrap {
  overflow-x: auto;
  margin: 16px 0;
}
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-heading);
  font-size: 14px;
  text-align: left;
}
.data-table th {
  background: var(--color-primary-dark);
  color: var(--color-text-light);
  font-weight: 600;
  padding: 12px 16px;
  border: 1px solid var(--color-primary-medium);
}
.data-table td {
  padding: 10px 16px;
  border: 1px solid var(--color-border-light);
  background: var(--color-background-cream);
}
.data-table tr:nth-child(even) td {
  background: rgba(10, 43, 78, 0.03);
}
.data-table .highlight {
  color: var(--color-highlight-red);
  font-weight: 700;
}
.data-table .gold {
  color: var(--color-accent-gold);
  font-weight: 700;
}
/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }
  .visual-focus h1,
  .visual-focus .focus-title {
    font-size: 34px;
  }
}
@media (max-width: 768px) {
  .header-inner {
    padding: 0 16px;
  }
  .nav-toggle {
    display: flex;
  }
  .main-nav {
    position: fixed;
    top: var(--header-height);
    left: 0;
    width: 100%;
    background: var(--color-primary-dark);
    padding: 16px 24px 24px;
    box-shadow: 0 8px 24px rgba(10, 43, 78, 0.3);
    transform: translateY(-120%);
    opacity: 0;
    visibility: hidden;
    transition: transform 0.4s ease, opacity 0.4s ease, visibility 0.4s ease;
  }
  .main-nav[data-open] {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }
  .nav-list {
    flex-direction: column;
    gap: 4px;
  }
  .nav-link {
    padding: 12px 16px;
    font-size: 16px;
  }
  .nav-link::after {
    display: none;
  }
  .nav-link[aria-current="page"] {
    background: rgba(212,175,55,0.15);
    color: var(--color-accent-gold);
  }
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }
  .grid {
    grid-template-columns: 1fr;
  }
  .visual-focus h1,
  .visual-focus .focus-title {
    font-size: 28px;
  }
  .visual-focus .focus-sub {
    font-size: 16px;
  }
  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 44px;
    height: 44px;
  }
  .container {
    padding: 0 16px;
  }
  .content-section {
    padding: 32px 0;
  }
}
@media (max-width: 480px) {
  .brand-name {
    font-size: 18px;
  }
  .visual-focus h1,
  .visual-focus .focus-title {
    font-size: 24px;
  }
}
/* ===== Reduced Motion ===== */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  html {
    scroll-behavior: auto;
  }
  .card:hover {
    transform: none;
  }
  .back-to-top {
    transition: opacity 0.01ms ease, visibility 0.01ms ease;
  }
}
/* ===== Utility ===== */
.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;
}
.text-center {
  text-align: center;
}
.text-gold {
  color: var(--color-accent-gold);
}
.text-red {
  color: var(--color-highlight-red);
}
.mt-1 { margin-top: 8px; }
.mt-2 { margin-top: 16px; }
.mt-3 { margin-top: 24px; }
.mb-1 { margin-bottom: 8px; }
.mb-2 { margin-bottom: 16px; }
.mb-3 { margin-bottom: 24px; }