*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --clr-primary: #00D4FF;
  --clr-accent: #FF2E4C;
  --clr-bg: #0B0C10;
  --clr-card: #14161E;
  --clr-surface: #1C1F28;
  --clr-text: #F5F7FA;
  --clr-text-secondary: #A0A8B8;
  --clr-success: #00FF9D;
  --clr-warning: #FFC24B;
  --clr-border: rgba(255, 255, 255, 0.12);
  --font-display: Oswald, Impact, 'Arial Narrow', sans-serif;
  --font-body: Inter, 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-full: 999px;
  --container-max: 1440px;
  --header-top: 16px;
  --header-h: 56px;
  --space-2xs: 4px;
  --space-xs: 8px;
  --space-sm: 16px;
  --space-md: 24px;
  --space-lg: 40px;
  --space-xl: 64px;
  --space-2xl: 96px;
  --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.4);
  --shadow-float: 0 12px 40px rgba(0, 0, 0, 0.6);
  --ease-out: 300ms ease-out;
  --fz-xs: 12px;
  --fz-sm: 14px;
  --fz-md: 16px;
  --fz-lg: 20px;
  --fz-xl: 28px;
  --fz-2xl: 36px;
  --fz-3xl: 48px;
  --fz-4xl: 64px;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: var(--fz-md);
  line-height: 1.7;
  color: var(--clr-text);
  background-color: var(--clr-bg);
  background-image:
    radial-gradient(ellipse at 20% -10%, rgba(0, 212, 255, 0.09) 0%, transparent 50%),
    radial-gradient(ellipse at 90% 15%, rgba(255, 46, 76, 0.06) 0%, transparent 35%);
  background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
  padding-top: calc(var(--header-top) + var(--header-h) + 24px);
}

::selection {
  background: var(--clr-primary);
  color: var(--clr-bg);
}

#main-content {
  scroll-margin-top: 96px;
  outline: none;
}

:focus-visible {
  outline: 2px solid var(--clr-primary);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ---------- 跳过链接 ---------- */
.skip-link {
  position: fixed;
  top: -120px;
  left: 16px;
  z-index: 3000;
  background: var(--clr-primary);
  color: var(--clr-bg);
  font-weight: 700;
  font-size: var(--fz-sm);
  padding: 10px 22px;
  border-radius: var(--radius-full);
  text-decoration: none;
  transition: top 0.3s ease-out;
  box-shadow: 0 4px 20px rgba(0, 212, 255, 0.4);
}
.skip-link:focus {
  top: 12px;
}

/* ---------- 头部悬浮胶囊 ---------- */
.site-header {
  position: fixed;
  top: var(--header-top);
  left: 50%;
  transform: translateX(-50%);
  z-index: 1000;
  width: min(calc(100% - 32px), 1320px);
  background: rgba(13, 14, 20, 0.86);
  -webkit-backdrop-filter: blur(18px);
  backdrop-filter: blur(18px);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-full);
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.45);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
  padding: 0 12px 0 20px;
}

.brand {
  display: flex;
  align-items: center;
  text-decoration: none;
  gap: 10px;
  color: var(--clr-text);
  flex-shrink: 0;
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  background: linear-gradient(135deg, var(--clr-primary) 0%, #00A8E0 100%);
  color: var(--clr-bg);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 16px;
  line-height: 1;
  clip-path: polygon(50% 0, 100% 50%, 50% 100%, 0 50%);
}

.brand-text {
  display: flex;
  align-items: baseline;
  gap: 6px;
  white-space: nowrap;
}

.brand-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--fz-lg);
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--clr-text);
  line-height: 1;
}

.brand-suffix {
  font-family: var(--font-body);
  font-size: var(--fz-xs);
  letter-spacing: 1px;
  color: var(--clr-primary);
  text-transform: uppercase;
  border: 1px solid rgba(0, 212, 255, 0.35);
  padding: 2px 6px;
  border-radius: var(--radius-full);
  line-height: 1.2;
}

.main-nav {
  display: flex;
  align-items: center;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
  list-style: none;
}

.nav-item {
  position: relative;
}

.nav-link {
  position: relative;
  display: inline-block;
  padding: 8px 14px;
  border-radius: var(--radius-full);
  color: var(--clr-text-secondary);
  font-size: var(--fz-sm);
  font-weight: 500;
  text-decoration: none;
  letter-spacing: 0.3px;
  transition: color 0.25s, background 0.25s;
}

.nav-link:hover {
  color: var(--clr-text);
  background: rgba(255, 255, 255, 0.06);
}

.nav-link[aria-current="page"] {
  color: var(--clr-primary);
  background: rgba(0, 212, 255, 0.08);
}

.nav-link[aria-current="page"]::after {
  content: '';
  position: absolute;
  left: 50%;
  bottom: 2px;
  transform: translateX(-50%);
  width: 12px;
  height: 2px;
  background: var(--clr-primary);
  border-radius: 2px;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 9px 20px;
  border-radius: var(--radius-full);
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 13px;
  letter-spacing: 1px;
  text-transform: uppercase;
  text-decoration: none;
  cursor: pointer;
  border: 1px solid transparent;
  line-height: 1.2;
  transition: background var(--ease-out), color var(--ease-out), transform var(--ease-out), box-shadow var(--ease-out);
}

.btn-primary {
  background: var(--clr-primary);
  color: var(--clr-bg);
  box-shadow: 0 0 18px rgba(0, 212, 255, 0.25);
}

.btn-primary:hover {
  background: #66E4FF;
  transform: translateY(-2px);
  box-shadow: 0 0 30px rgba(0, 212, 255, 0.4);
}

/* ---------- 汉堡按钮 ---------- */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  cursor: pointer;
  position: relative;
  transition: background 0.25s;
  padding: 0;
}
.nav-toggle:hover {
  background: var(--clr-surface);
}
.nav-toggle .nav-toggle-bar {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--clr-text);
  margin: 4px auto;
  border-radius: 2px;
  transition: transform 0.3s ease-out, opacity 0.3s ease-out;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2) {
  opacity: 0;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

/* ---------- 阅读进度 ---------- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0%;
  background: linear-gradient(to right, var(--clr-primary), var(--clr-accent));
  z-index: 2000;
  box-shadow: 0 0 10px rgba(0, 212, 255, 0.4);
  pointer-events: none;
}

/* ---------- 返回顶部 ---------- */
.back-top {
  position: fixed;
  bottom: 24px;
  right: 24px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  color: var(--clr-primary);
  font-size: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity 0.3s, transform 0.3s, visibility 0.3s, background 0.3s, color 0.3s, border-color 0.3s;
  z-index: 950;
  box-shadow: var(--shadow-card);
}
.back-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.back-top:hover {
  background: var(--clr-primary);
  color: var(--clr-bg);
  border-color: var(--clr-primary);
}

/* ---------- 页脚 ---------- */
.site-footer {
  margin-top: var(--space-2xl);
  background: var(--clr-card);
  border-top: 1px solid var(--clr-border);
  position: relative;
}
.site-footer::before {
  content: '';
  position: absolute;
  top: -1px;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(to right, var(--clr-primary), transparent 60%, var(--clr-accent));
}

.footer-main {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: var(--space-xl) clamp(16px, 4vw, 48px) var(--space-lg);
  display: grid;
  grid-template-columns: 2fr 1fr 1.4fr;
  gap: var(--space-lg);
}

.footer-brand .brand {
  margin-bottom: var(--space-sm);
}

.footer-brand-line {
  font-family: var(--font-display);
  font-size: var(--fz-lg);
  font-weight: 600;
  color: var(--clr-text);
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: var(--space-xs);
  line-height: 1.2;
}

.footer-trust {
  font-size: var(--fz-xs);
  color: var(--clr-text-secondary);
  line-height: 1.6;
  border-left: 2px solid var(--clr-primary);
  padding-left: var(--space-sm);
  margin-top: var(--space-sm);
}

.footer-links ul {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-xs) var(--space-sm);
}

.footer-links a {
  color: var(--clr-text-secondary);
  text-decoration: none;
  font-size: var(--fz-sm);
  transition: color 0.3s;
}
.footer-links a:hover {
  color: var(--clr-primary);
}

.footer-contact {
  font-style: normal;
}

.footer-contact-item {
  font-size: var(--fz-sm);
  color: var(--clr-text-secondary);
  display: flex;
  align-items: flex-start;
  gap: 8px;
  margin-bottom: var(--space-xs);
  line-height: 1.5;
}
.footer-contact-item::before {
  content: '';
  width: 4px;
  height: 4px;
  background: var(--clr-primary);
  border-radius: 50%;
  transform: translateY(6px);
  flex-shrink: 0;
}

.footer-bottom {
  border-top: 1px solid var(--clr-border);
  padding: var(--space-sm) clamp(16px, 4vw, 48px);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-xs);
  max-width: var(--container-max);
  margin: 0 auto;
  font-size: var(--fz-xs);
  color: var(--clr-text-secondary);
}
.footer-icp,
.footer-note {
  margin: 0;
}

/* ---------- 内容容器与章节 ---------- */
.content-container {
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: clamp(16px, 4vw, 48px);
}

.section {
  padding-block: var(--space-xl);
}
.section-tight {
  padding-block: var(--space-lg);
}

.section-head {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: var(--space-md);
  flex-wrap: wrap;
  margin-bottom: var(--space-lg);
}

.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-display);
  font-size: var(--fz-xs);
  font-weight: 600;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--clr-primary);
  margin-bottom: var(--space-xs);
}
.section-kicker::before {
  content: '';
  width: 24px;
  height: 2px;
  background: var(--clr-primary);
  display: inline-block;
  flex-shrink: 0;
}

.section-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--fz-2xl);
  line-height: 1;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--clr-text);
  max-width: 20ch;
}

/* ---------- 页面首屏 ---------- */
.page-hero {
  position: relative;
  padding: var(--space-2xl) 0 var(--space-lg);
  border-bottom: 1px solid var(--clr-border);
  margin-bottom: var(--space-xl);
}
.page-hero::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 120px;
  height: 2px;
  background: var(--clr-primary);
  box-shadow: 0 0 12px rgba(0, 212, 255, 0.5);
}

/* ---------- Bento 网格 ---------- */
.bento-grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: var(--space-sm);
}

.bento-cell {
  background: var(--clr-card);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  padding: var(--space-md);
  box-shadow: var(--shadow-card);
  transition: transform var(--ease-out), border-color var(--ease-out), box-shadow var(--ease-out);
}
.bento-cell:hover {
  border-color: rgba(0, 212, 255, 0.25);
  box-shadow: var(--shadow-float);
}

/* ---------- 卡片 ---------- */
.card {
  background: var(--clr-card);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  padding: var(--space-md);
  box-shadow: var(--shadow-card);
  transition: transform var(--ease-out), border-color var(--ease-out), box-shadow var(--ease-out);
}
.card-hover:hover {
  transform: translateY(-4px);
  border-color: rgba(0, 212, 255, 0.3);
  box-shadow: var(--shadow-float);
}

/* ---------- 数据胶囊 ---------- */
.data-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-full);
  font-size: var(--fz-xs);
  color: var(--clr-text-secondary);
  font-weight: 600;
  letter-spacing: 0.5px;
  white-space: nowrap;
}
.data-chip[data-tone="primary"] {
  color: var(--clr-primary);
  border-color: rgba(0, 212, 255, 0.4);
  background: rgba(0, 212, 255, 0.08);
}
.data-chip[data-tone="accent"] {
  color: var(--clr-accent);
  border-color: rgba(255, 46, 76, 0.4);
  background: rgba(255, 46, 76, 0.08);
}
.data-chip[data-tone="success"] {
  color: var(--clr-success);
  border-color: rgba(0, 255, 157, 0.4);
  background: rgba(0, 255, 157, 0.08);
}

/* ---------- 大数据展示 ---------- */
.stat-display {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--fz-4xl);
  line-height: 0.9;
  color: var(--clr-primary);
  letter-spacing: 1px;
}
.stat-display[data-tone="accent"] {
  color: var(--clr-accent);
}
.stat-display[data-tone="success"] {
  color: var(--clr-success);
}
.stat-display[data-tone="warning"] {
  color: var(--clr-warning);
}
.stat-label {
  font-size: var(--fz-xs);
  color: var(--clr-text-secondary);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-top: var(--space-2xs);
}

/* ---------- 面包屑 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px;
  list-style: none;
  padding: 0;
  margin: 0 0 var(--space-md);
  font-size: var(--fz-xs);
  color: var(--clr-text-secondary);
}
.breadcrumb li {
  display: flex;
  align-items: center;
  gap: 6px;
}
.breadcrumb li + li::before {
  content: '/';
  color: var(--clr-text-secondary);
  opacity: 0.5;
}
.breadcrumb a {
  color: var(--clr-text-secondary);
  text-decoration: none;
  transition: color 0.3s;
}
.breadcrumb a:hover {
  color: var(--clr-primary);
}
.breadcrumb [aria-current="page"] {
  color: var(--clr-text);
  font-weight: 600;
}

/* ---------- 斜向分隔带 ---------- */
.diagonal-band {
  position: relative;
  height: 32px;
  overflow: hidden;
}
.diagonal-band::before {
  content: '';
  position: absolute;
  left: -2%;
  right: -2%;
  top: 50%;
  height: 2px;
  background: linear-gradient(to right, transparent, var(--clr-primary) 25%, var(--clr-accent) 75%, transparent);
  transform: rotate(-1deg);
}

/* ---------- 更多链接 ---------- */
.link-more {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--clr-primary);
  font-family: var(--font-display);
  font-size: var(--fz-sm);
  font-weight: 600;
  text-decoration: none;
  text-transform: uppercase;
  letter-spacing: 1px;
  transition: gap 0.3s, color 0.3s;
}
.link-more::after {
  content: '→';
  transition: transform 0.3s;
}
.link-more:hover {
  gap: 10px;
  color: #66E4FF;
}
.link-more:hover::after {
  transform: translateX(2px);
}

/* ---------- 滚动显现 ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
  will-change: opacity, transform;
}
[data-reveal].is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- 平板 ---------- */
@media (max-width: 1024px) {
  .footer-main {
    grid-template-columns: 1fr 1fr;
  }
  .footer-brand {
    grid-column: 1 / -1;
  }
  .section-title {
    font-size: var(--fz-xl);
  }
  .stat-display {
    font-size: var(--fz-3xl);
  }
}

/* ---------- 手机 ---------- */
@media (max-width: 768px) {
  :root {
    --header-top: 12px;
    --header-h: 52px;
  }
  body {
    padding-top: calc(var(--header-top) + var(--header-h) + 16px);
  }

  .site-header {
    top: var(--header-top);
    width: calc(100% - 24px);
    border-radius: 18px;
  }
  .header-inner {
    height: var(--header-h);
    padding: 0 10px 0 14px;
  }
  .brand-name {
    font-size: 18px;
  }
  .brand-suffix {
    display: none;
  }
  .brand-mark {
    width: 30px;
    height: 30px;
    font-size: 15px;
  }

  .main-nav {
    position: absolute;
    top: calc(100% + 8px);
    left: 12px;
    right: 12px;
    background: var(--clr-card);
    border-radius: 16px;
    padding: 10px;
    border: 1px solid var(--clr-border);
    box-shadow: var(--shadow-float);
    display: none;
  }
  .main-nav[data-open] {
    display: block;
  }
  .nav-list {
    flex-direction: column;
    gap: 2px;
  }
  .nav-link {
    display: block;
    width: 100%;
    padding: 12px 16px;
    border-radius: 10px;
    text-align: center;
  }
  .nav-link[aria-current="page"]::after {
    display: none;
  }
  .nav-toggle {
    display: block;
  }

  .header-actions .btn-primary {
    padding: 8px 14px;
    font-size: 12px;
  }

  .footer-main {
    grid-template-columns: 1fr;
    gap: var(--space-md);
    padding-top: var(--space-lg);
  }
  .footer-brand {
    grid-column: auto;
  }
  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
  .footer-links ul {
    grid-template-columns: repeat(2, 1fr);
  }

  .bento-grid {
    gap: 12px;
  }
  .bento-cell {
    padding: var(--space-sm);
  }
  .page-hero {
    padding: var(--space-xl) 0 var(--space-md);
    margin-bottom: var(--space-lg);
  }
}

/* ---------- Reduced Motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
  [data-reveal] {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }
  .scroll-progress {
    display: none;
  }
  .back-top {
    transition: opacity 0.01ms, transform 0.01ms;
  }
  .site-header,
  .header-inner,
  .nav-toggle,
  .btn,
  .card,
  .bento-cell,
  .link-more {
    transition: none !important;
  }
}