:root {
  /* 优化后的色彩系统 */
  --bg: #fafbfc;
  --bg-subtle: #ffffff;
  --panel: #ffffff;
  --card: #ffffff;
  --card-soft: #f8fafc;
  --card-hover: #f1f5f9;
  --border: #e2e8f0;
  --border-light: #f1f5f9;
  --text: #1a202c;
  --text-muted: #64748b;
  --text-subtle: #94a3b8;
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: #dbeafe;
  --primary-subtle: #eff6ff;
  --primary-strong: #1e40af;
  --accent: #0891b2;
  --accent-hover: #0e7490;
  --accent-light: #ecfeff;
  --success: #10b981;
  --success-light: #d1fae5;
  --warning: #f59e0b;
  --warning-light: #fef3c7;
  --error: #ef4444;
  --error-light: #fee2e2;

  /* 优化的阴影系统 */
  --shadow-xs: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px -1px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);

  /* 优化的间距系统 */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;

  /* 其他变量 */
  --shell-width: 1200px;
  --border-radius: 12px;
  --border-radius-lg: 16px;
  --border-radius-xl: 20px;
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 350ms ease;
}

/* 动画定义 */
@keyframes pulse-glow {
  0% { box-shadow: 0 0 0 0 rgba(37, 99, 235, 0.4); }
  70% { box-shadow: 0 0 0 10px rgba(37, 99, 235, 0); }
  100% { box-shadow: 0 0 0 0 rgba(37, 99, 235, 0); }
}

@keyframes shine {
  0% { left: -100%; opacity: 0; }
  20% { left: -100%; opacity: 0.5; }
  100% { left: 100%; opacity: 0; }
}

@keyframes float {
  0% { transform: translateY(0px); }
  50% { transform: translateY(-5px); }
  100% { transform: translateY(0px); }
}

.animate-pulse {
  animation: pulse-glow 2s infinite;
}

.animate-float {
  animation: float 3s ease-in-out infinite;
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  font-size: 16px;
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

/* 优化的链接样式 */
a {
  color: var(--primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--primary-hover);
  text-decoration: underline;
}

/* 优化的段落样式 */
p {
  margin: 0 0 1rem;
  color: var(--text);
  max-width: 65ch;
}

/* 优化的标题样式 */
h1,
h2,
h3,
h4,
h5,
h6 {
  margin: 0 0 0.75rem;
  line-height: 1.25;
  letter-spacing: -0.025em;
  font-weight: 600;
  color: var(--text);
}

h1 {
  font-size: 2.25rem;
  font-weight: 700;
  letter-spacing: -0.04em;
  line-height: 1.2;
}

h2 {
  font-size: 1.875rem;
  font-weight: 600;
  margin-top: 3rem;
}

h3 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-top: 2rem;
}

h4 {
  font-size: 1.25rem;
  font-weight: 600;
}

/* 优化的列表样式 */
ul, ol {
  margin: 0 0 1rem;
  padding-left: 1.5rem;
}

li {
  margin-bottom: 0.5rem;
  color: var(--text);
}

/* 优化的强调样式 */
strong, b {
  font-weight: 600;
  color: var(--text);
}

em, i {
  font-style: italic;
}

/* 优化的代码样式 */
code {
  font-family: "Fira Code", "SF Mono", Monaco, Consolas, monospace;
  background: var(--card-soft);
  padding: 0.125rem 0.375rem;
  border-radius: 4px;
  font-size: 0.875em;
  color: var(--primary);
}

pre {
  background: var(--card-soft);
  border: 1px solid var(--border);
  border-radius: var(--border-radius);
  padding: var(--space-lg);
  overflow-x: auto;
  font-size: 0.875rem;
}

pre code {
  background: none;
  padding: 0;
  color: var(--text);
}

/* 优化的引用样式 */
blockquote {
  margin: 1.5rem 0;
  padding: var(--space-lg) var(--space-xl);
  border-left: 4px solid var(--primary);
  background: var(--primary-subtle);
  border-radius: 0 var(--border-radius) var(--border-radius) 0;
}

blockquote p {
  margin: 0;
  font-style: italic;
  color: var(--text-muted);
}

/* 优化的图片样式 */
img {
  max-width: 100%;
  display: block;
  height: auto;
  border-radius: var(--border-radius);
}

/* 容器样式 */
.shell {
  max-width: var(--shell-width);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

@media (min-width: 640px) {
  .shell {
    padding: 0 var(--space-xl);
  }
}

/* 页面和布局样式 */
.page {
  background: transparent;
}

.section {
  padding: var(--space-3xl) 0;
}

@media (min-width: 1024px) {
  .section {
    padding: calc(var(--space-3xl) * 1.5) 0;
  }
}

/* 布局工具类 */
.stack {
  display: grid;
  gap: var(--space-lg);
}

.stack.tight {
  gap: var(--space-md);
}

.stack.loose {
  gap: var(--space-xl);
}

.grid {
  display: grid;
  gap: var(--space-lg);
}

.grid.two {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.grid.three {
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
}

.grid.four {
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

/* Flexbox 工具类 */
.flex {
  display: flex;
}

.flex.col {
  flex-direction: column;
}

.flex.wrap {
  flex-wrap: wrap;
}

.flex.center {
  align-items: center;
  justify-content: center;
}

.flex.between {
  justify-content: space-between;
}

.flex.gap-sm {
  gap: var(--space-sm);
}

.flex.gap-md {
  gap: var(--space-md);
}

.flex.gap-lg {
  gap: var(--space-lg);
}

/* 站点头部样式 - 修复版本 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(16px) saturate(180%);
  -webkit-backdrop-filter: blur(16px) saturate(180%);
  border-bottom: 1px solid var(--border-light);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base);
}

.site-header.scrolled {
  background: rgba(255, 255, 255, 0.98);
  box-shadow: var(--shadow-md);
}

.site-header .shell {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

/* 品牌样式 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.025em;
  color: var(--text);
  transition: transform var(--transition-base);
}

.brand:hover {
  transform: scale(1.02);
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--border-radius);
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-hover) 100%);
  color: #ffffff;
  font-weight: 800;
  font-size: 1.25rem;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.brand-mark::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(45deg, rgba(255,255,255,0.1) 0%, transparent 50%);
  opacity: 0;
  transition: opacity var(--transition-base);
}

.brand:hover .brand-mark::before {
  opacity: 1;
}

.brand-name {
  font-family: "Inter", sans-serif;
  font-size: 1.125rem;
  font-weight: 700;
}

/* 导航样式 */
.nav {
  position: relative;
}

.nav ul {
  display: flex;
  gap: var(--space-sm);
  padding: 0;
  margin: 0;
  list-style: none;
}

.nav a {
  display: inline-flex;
  align-items: center;
  padding: 0.625rem 1.125rem;
  border-radius: var(--border-radius);
  color: var(--text);
  font-weight: 500;
  font-size: 0.95rem;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.nav a::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: all var(--transition-base);
  transform: translateX(-50%);
}

.nav a:hover::before,
.nav a.active::before {
  width: 80%;
}

.nav a:hover,
.nav a.active {
  color: var(--primary);
  background: var(--primary-subtle);
}

/* 下拉菜单箭头指示器 */
.nav .dropdown > a {
  position: relative;
  padding-right: 2rem;
}

.nav .dropdown > a::after {
  content: '⌄';
  position: absolute;
  right: 1rem;
  top: 50%;
  transform: translateY(-50%);
  font-size: 0.75rem;
  opacity: 0.5;
  transition: all var(--transition-base);
  color: var(--text-muted);
}

.nav .dropdown:hover > a::after {
  opacity: 1;
  transform: translateY(-50%) rotate(180deg);
}

/* 导航切换按钮 */
.nav-toggle {
  display: none;
  background: var(--card);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 0.625rem 0.75rem;
  border-radius: var(--border-radius);
  cursor: pointer;
  font-size: 1.25rem;
  transition: all var(--transition-base);
  box-shadow: var(--shadow-xs);
}

.nav-toggle:hover {
  background: var(--card-hover);
  transform: scale(1.05);
}

.nav-toggle:active {
  transform: scale(0.95);
}

/* 下拉菜单样式 - 桌面端 */
.nav .dropdown {
  position: relative;
}

/* 增加透明桥梁，防止鼠标移动时菜单消失 */
.nav .dropdown::after {
  content: '';
  position: absolute;
  top: 100%;
  left: 0;
  width: 100%;
  height: var(--space-md);
  background: transparent;
  display: block;
}

.nav .dropdown-menu {
  display: block; /* 强制竖排，覆盖 .nav ul 的 flex */
  position: absolute;
  top: calc(100% + var(--space-md));
  left: 50%;
  transform: translateX(-50%) translateY(-8px) scale(0.96);
  min-width: 220px;
  background: rgba(255, 255, 255, 0.98);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border: 1px solid var(--border);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-xl);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-slow);
  padding: var(--space-sm) 0;
  margin-top: 0;
  z-index: 100;
  overflow: hidden;
}

.nav .dropdown::before {
  content: '';
  position: absolute;
  top: calc(100% + var(--space-md) - 6px);
  left: 50%;
  width: 12px;
  height: 12px;
  background: rgba(255, 255, 255, 0.98);
  border-left: 1px solid var(--border);
  border-top: 1px solid var(--border);
  transform: translateX(-50%) rotate(45deg) translateY(5px);
  opacity: 0;
  transition: all var(--transition-base);
  z-index: 101;
  pointer-events: none;
}

.nav .dropdown:hover::before {
  opacity: 1;
  transform: translateX(-50%) rotate(45deg) translateY(0);
}

.nav .dropdown:hover .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0) scale(1);
}

.nav .dropdown-menu li {
  list-style: none;
  margin: 0;
  position: relative;
}

.nav .dropdown-menu li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--primary);
  transform: scaleY(0);
  transition: transform 0.2s ease;
}

.nav .dropdown-menu li:hover::before {
  transform: scaleY(1);
}

.nav .dropdown-menu a {
  display: block;
  padding: 0.75rem 1.5rem 0.75rem 1.8rem;
  color: var(--text);
  font-weight: 500;
  font-size: 0.9rem;
  border-radius: 0;
  background: transparent;
  transition: all 0.2s ease;
  position: relative;
  overflow: hidden;
}

.nav .dropdown-menu a::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  right: 0;
  bottom: 0;
  background: var(--primary-light);
  opacity: 0;
  transition: opacity 0.2s ease;
}

.nav .dropdown-menu a:hover {
  color: var(--primary);
  transform: translateX(5px);
}

.nav .dropdown-menu a:hover::before {
  opacity: 1;
}

.nav .dropdown-menu a:first-child {
  border-radius: 8px 8px 0 0;
}

.nav .dropdown-menu a:last-child {
  border-radius: 0 0 8px 8px;
}

.nav .dropdown-menu a.active {
  color: var(--primary);
  font-weight: 600;
  background: var(--primary-light);
}

.nav .dropdown-menu a.active::before {
  opacity: 1;
  background: var(--primary-light);
}

.hero {
  padding: 5.5rem 0 4rem;
  overflow: hidden; /* 防止动画溢出 */
}

.hero .shell > div {
  animation: fade-up 0.8s ease-out forwards;
  opacity: 0;
}

.hero .shell > div:nth-child(2) {
  animation-delay: 0.2s;
}

@keyframes fade-up {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.hero .shell {
  display: grid;
  gap: 2rem;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  align-items: center;
}

.hero h1 {
  font-size: clamp(2.3rem, 4vw, 3rem);
}

.hero .lede {
  color: var(--text-muted);
  font-size: 1.1rem;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-xs) var(--space-md);
  border-radius: 9999px;
  background: var(--card-soft);
  border: 1px solid var(--border);
  color: var(--text);
  font-weight: 500;
  font-size: 0.875rem;
  transition: all var(--transition-base);
}

.pill:hover {
  background: var(--card-hover);
  transform: scale(1.05);
}

.pill.primary {
  background: var(--primary-light);
  border-color: var(--primary);
  color: var(--primary);
}

.pill.success {
  background: var(--success-light);
  border-color: var(--success);
  color: var(--success);
}

.pill.warning {
  background: var(--warning-light);
  border-color: var(--warning);
  color: var(--warning);
}

.btn-row {
  display: flex;
  gap: 0.8rem;
  flex-wrap: wrap;
  margin-top: 1.4rem;
}

/* 按钮样式 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 0.75rem 1.5rem;
  border-radius: var(--border-radius);
  border: 1px solid var(--border);
  color: var(--text);
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: 0.025em;
  background: var(--card);
  transition: all var(--transition-base);
  cursor: pointer;
  text-decoration: none;
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(45deg, rgba(255,255,255,0.1) 0%, transparent 100%);
  opacity: 0;
  transition: opacity var(--transition-base);
}

.btn:hover::before {
  opacity: 1;
}

/* 按钮变体 */
.btn.primary {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-hover) 100%);
  border-color: var(--primary);
  color: #ffffff;
  box-shadow: var(--shadow-md);
  animation: pulse-glow 3s infinite; /* 添加脉冲动画 */
}

.btn.primary:hover {
  transform: translateY(-2px) scale(1.02); /* 增加缩放 */
  box-shadow: var(--shadow-lg), 0 0 20px rgba(37, 99, 235, 0.4); /* 增加发光 */
}

.btn.primary::after {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 50%;
  height: 100%;
  background: linear-gradient(to right, rgba(255,255,255,0) 0%, rgba(255,255,255,0.3) 50%, rgba(255,255,255,0) 100%);
  transform: skewX(-25deg);
  transition: none;
}

.btn.primary:hover::after {
  animation: shine 0.75s;
}

.btn.ghost {
  background: transparent;
  border-color: var(--border);
  color: var(--text);
  padding-right: 2rem; /* 为箭头留出空间 */
  position: relative;
}

.btn.ghost::after {
  content: '→';
  position: absolute;
  right: 1.2rem;
  transition: transform var(--transition-base), opacity var(--transition-base);
  opacity: 0.6;
}

.btn.ghost:hover {
  background: var(--card-soft);
  border-color: var(--primary);
  color: var(--primary);
  padding-right: 2.5rem; /* 稍微加宽 */
}

.btn.ghost:hover::after {
  transform: translateX(5px);
  opacity: 1;
}

.btn.secondary {
  background: var(--accent);
  border-color: var(--accent);
  color: #ffffff;
}

.btn.secondary:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
}

/* 按钮尺寸 */
.btn.sm {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

.btn.lg {
  padding: 1rem 2rem;
  font-size: 1.125rem;
}

/* 按钮状态 */
.btn:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
}

.btn:active {
  transform: scale(0.98);
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

/* 卡片样式 */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--border-radius-lg);
  padding: var(--space-xl);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, transparent 0%, rgba(37, 99, 235, 0.02) 100%);
  opacity: 0;
  transition: opacity var(--transition-base);
}

.card:hover {
  transform: translateY(-8px); /* 更明显的上浮 */
  box-shadow: var(--shadow-2xl); /* 更深的阴影 */
  border-color: var(--primary-light); /* 边框变色 */
}

.card:focus-within {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
  border-color: var(--primary);
  outline: none;
}

.card:hover::before {
  opacity: 1;
}

.card.soft {
  background: var(--card-soft);
  border-color: var(--border-light);
}

.card.interactive {
  cursor: pointer;
}

.card.interactive:active {
  transform: translateY(-2px);
}

/* 标签和徽章样式 */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.75rem;
  border-radius: 9999px;
  background: var(--primary-light);
  color: var(--primary-strong);
  font-weight: 600;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.pill-grid {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.pill-grid .pill {
  background: var(--primary-light);
  border-color: var(--primary);
  color: var(--primary-strong);
}

/* 指标样式 */
.metrics {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
}

.metric {
  padding: 1.2rem 1.1rem;
  border-radius: 14px;
  background: var(--card-soft);
  border: 1px solid var(--border);
  text-align: center;
  transition: all var(--transition-base);
}

.metric:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.metric strong {
  display: block;
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: var(--space-xs);
}

.metric small {
  color: var(--text-muted);
  font-size: 0.875rem;
}

.panel {
  background: var(--panel);
  border-radius: 22px;
  border: 1px solid var(--border);
  padding: 2rem;
  box-shadow: var(--shadow-sm);
}

.split {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 1.5rem;
  align-items: start;
}

.list-check {
  padding: 0;
  margin: 0;
  list-style: none;
  display: grid;
  gap: 0.8rem;
}

.list-check li {
  display: flex;
  gap: 0.6rem;
  color: var(--text-muted);
}

.list-check li::before {
  content: "*";
  color: var(--accent);
  margin-top: -0.1rem;
}

.table {
  width: 100%;
  border-collapse: collapse;
  border: 1px solid var(--border);
}

.table th,
.table td {
  padding: 0.9rem;
  border-bottom: 1px solid var(--border);
  text-align: left;
}

.table th {
  color: var(--text-muted);
  font-weight: 700;
}

.case-card h4 {
  color: var(--text);
  margin-bottom: 0.4rem;
}

.case-card p {
  color: var(--text-muted);
}

.cta {
  padding: 4rem 0;
}

.cta .cta-card {
  display: grid;
  gap: 1.2rem;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  align-items: center;
  background: var(--card-soft);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 1.8rem;
  box-shadow: var(--shadow-sm);
}

.cta-actions {
  display: flex;
  gap: 0.8rem;
  flex-wrap: wrap;
}

.services-grid {
  display: grid;
  gap: 1.2rem;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.service-card h3 {
  margin-bottom: 0.4rem;
}

.service-meta {
  display: flex;
  gap: 0.8rem;
  flex-wrap: wrap;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.badge.green {
  background: #dcfce7;
  color: #16a34a;
}

.timeline {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
}

.timeline .step {
  border: 1px dashed var(--border);
  border-radius: 14px;
  padding: 1rem;
  background: #f8fafc;
}

.skills {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}

.skills span {
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  background: #eef2f7;
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-weight: 600;
}

.site-footer {
  margin-top: 4rem;
  padding: 3rem 0 2rem;
  border-top: 1px solid var(--border);
  background: #f8fafc;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
}

.site-footer h4 {
  margin-bottom: 0.8rem;
}

.plain {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.4rem;
}

.footer-bottom {
  margin-top: 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.muted {
  color: var(--text-muted);
}

.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--accent);
  font-weight: 800;
  font-size: 0.8rem;
}

.hero-article {
  padding-bottom: 2rem;
}

.hero-article h1 {
  margin-bottom: 0.5rem;
}

.meta-row,
.tag-row {
  display: flex;
  gap: 0.8rem;
  flex-wrap: wrap;
  color: var(--text-muted);
}

.tag {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.65rem;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--card-soft);
  font-weight: 500;
  color: var(--text-muted);
}

.article-shell {
  padding: 0 0 2rem;
}

.article-body {
  background: var(--panel);
  border-radius: 18px;
  border: 1px solid var(--border);
  padding: 2rem;
  box-shadow: var(--shadow-sm);
  line-height: 1.8;
  max-width: 900px;
}

.article-body h1,
.article-body h2,
.article-body h3,
.article-body h4 {
  margin-top: 1.6rem;
  color: var(--text);
}

.article-body h1 {
  font-size: 2rem;
}

.article-body h2 {
  font-size: 1.5rem;
}

.article-body h3 {
  font-size: 1.25rem;
}

.article-body p {
  color: var(--text);
  font-size: 1rem;
}

.article-body a {
  color: var(--primary);
}

.article-body blockquote {
  border-left: 4px solid var(--primary);
  padding-left: 1rem;
  color: var(--text);
  background: #eef2f7;
  border-radius: 0 10px 10px 0;
}

.filter-row {
  display: flex;
  gap: 0.6rem;
  flex-wrap: wrap;
}

.filter-row button,
.filter-row a {
  border: 1px solid var(--border);
  background: #eef2f7;
  color: var(--text);
  border-radius: 12px;
  padding: 0.65rem 1rem;
  cursor: pointer;
  transition: all 0.2s ease;
  display: inline-flex;
  align-items: center;
  text-decoration: none;
}

.filter-row button.active,
.filter-row a.active {
  background: var(--primary);
  color: #ffffff;
  border-color: var(--primary);
}

.pager {
  margin-top: 1.25rem;
  display: flex;
  gap: 0.75rem;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
}

.pager-info {
  color: var(--text-muted);
  font-size: 0.95rem;
}

.btn.disabled {
  pointer-events: none;
  opacity: 0.55;
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1rem;
}

.article-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 1.3rem;
  display: grid;
  gap: 0.7rem;
}

.article-card h3 {
  margin: 0;
}

.article-card p {
  color: var(--text-muted);
}

.article-card .meta {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.badge.cat-google {
  background: var(--primary-light);
  color: var(--primary-strong);
}

.badge.cat-seo {
  background: #d1fae5;
  color: #065f46;
}

.badge.cat-marketing {
  background: #fed7aa;
  color: #9a3412;
}

.badge.cat-ecommerce {
  background: #e9d5ff;
  color: #6b21a8;
}

.contact-card {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
  align-items: center;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 1.8rem;
}

.qr-box {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 1rem;
  text-align: center;
}

.qr-box img {
  margin: 0 auto;
  border-radius: 12px;
  border: 6px solid var(--panel);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.35);
}

/* 响应式设计优化 */

/* 平板设备 (768px 及以下) */
@media (max-width: 768px) {
  .shell {
    padding: 0 var(--space-md);
  }

  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.5rem;
    margin-top: 2.5rem;
  }

  .section {
    padding: var(--space-2xl) 0;
  }

  /* 移动端导航 */
  .nav ul {
    position: fixed;
    top: 72px;
    right: 0;
    bottom: 0;
    flex-direction: column;
    width: 280px;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: var(--space-xl);
    border-radius: 0 0 0 var(--border-radius-lg);
    border: 1px solid var(--border);
    border-top: none;
    box-shadow: var(--shadow-2xl);
    transform: translateX(100%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-slow);
    overflow-y: auto;
  }

  .nav ul.open {
    transform: translateX(0);
    opacity: 1;
    visibility: visible;
  }

  .nav-toggle {
    display: inline-flex;
    z-index: 51;
  }

  .nav-toggle.active {
    background: var(--primary);
    color: #ffffff;
    border-color: var(--primary);
  }

  /* 移动端品牌 */
  .brand-name {
    font-size: 1rem;
  }

  /* 移动端按钮行 */
  .btn-row {
    flex-direction: column;
    gap: var(--space-sm);
  }

  .btn {
    width: 100%;
    justify-content: center;
  }

  /* 移动端卡片网格 */
  .grid.two {
    grid-template-columns: 1fr;
  }

  .grid.three {
    grid-template-columns: 1fr;
  }

  .grid.four {
    grid-template-columns: repeat(2, 1fr);
  }

  /* 移动端指标 */
  .metrics {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }

  /* 移动端Hero区域 */
  .hero .shell {
    gap: var(--space-xl);
  }

  /* 移动端面板 */
  .panel {
    padding: var(--space-lg);
    border-radius: var(--border-radius);
  }

  /* 移动端下拉菜单样式 - 修复版本 */
  .nav .dropdown {
    width: 100%;
  }

  .nav .dropdown-menu {
    position: static !important;
    opacity: 1 !important;
    visibility: visible !important;
    transform: none !important;
    box-shadow: none;
    border: 1px solid var(--border);
    background: var(--card-soft);
    margin: var(--space-sm) 0 0 0;
    padding: var(--space-sm) 0;
    max-height: 0;
    overflow: hidden;
    transition: all var(--transition-base);
    border-radius: var(--border-radius);
  }

  .nav .dropdown.open .dropdown-menu {
    max-height: 400px;
    box-shadow: var(--shadow-md);
  }

  .nav .dropdown > a {
    padding-right: 2rem;
  }

  .nav .dropdown > a::after {
    font-size: 0.8rem;
    right: 1rem;
    transition: all var(--transition-base);
  }

  .nav .dropdown.open > a::after {
    transform: translateY(-50%) rotate(180deg);
  }

  .nav .dropdown::before,
  .nav .dropdown::after {
    display: none;
  }

  .nav .dropdown-menu li {
    margin: 0;
  }

  .nav .dropdown-menu li::before {
    display: none;
  }

  .nav .dropdown-menu a {
    display: block !important;
    padding: var(--space-sm) var(--space-lg);
    font-size: 0.9rem;
    border-radius: 0;
    transition: all 0.2s ease;
    width: 100% !important;
    text-align: left;
    background: transparent;
  }

  .nav .dropdown-menu a:hover {
    background: var(--primary-subtle);
    transform: none;
  }

  .nav .dropdown-menu a:first-child {
    border-radius: 8px 8px 0 0;
  }

  .nav .dropdown-menu a:last-child {
    border-radius: 0 0 8px 8px;
  }

  .nav .dropdown-menu a.active {
    background: var(--primary-light);
    border-color: var(--primary);
    color: var(--primary);
  }
}

/* 手机设备 (480px 及以下) */
@media (max-width: 480px) {
  .shell {
    padding: 0 var(--space-sm);
  }

  h1 {
    font-size: 1.75rem;
  }

  h2 {
    font-size: 1.375rem;
  }

  h3 {
    font-size: 1.25rem;
  }

  p {
    max-width: none;
  }

  .nav ul {
    width: 100vw;
    border-radius: 0;
    padding: var(--space-lg);
  }

  .btn {
    padding: var(--space-md) var(--space-lg);
    font-size: 0.9rem;
  }

  .card {
    padding: var(--space-lg);
  }

  .grid.four {
    grid-template-columns: 1fr;
  }

  .article-body {
    padding: var(--space-lg);
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-sm);
  }
}

/* 大屏幕优化 (1400px 及以上) */
@media (min-width: 1400px) {
  .shell {
    max-width: 1320px;
  }

  h1 {
    font-size: 2.5rem;
  }

  .hero .shell {
    gap: var(--space-2xl);
  }
}

/* 动画优化 */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* 额外的工具类和增强样式 */

/* 可访问性增强 */
.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;
}

/* 焦点样式增强 */
.focus-ring:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
  border-radius: var(--border-radius);
}

/* 滚动条样式优化 */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--card-soft);
  border-radius: var(--border-radius);
}

::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: var(--border-radius);
  transition: background var(--transition-base);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* Firefox 滚动条 */
* {
  scrollbar-width: thin;
  scrollbar-color: var(--border) var(--card-soft);
}

/* 选中文本样式 */
::selection {
  background: var(--primary-light);
  color: var(--text);
}

::-moz-selection {
  background: var(--primary-light);
  color: var(--text);
}

/* 加载动画 */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateX(-20px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

/* 动画类 */
.animate-fade-in {
  animation: fadeIn 0.5s ease-out;
}

.animate-slide-in {
  animation: slideIn 0.5s ease-out;
}

.animate-pulse {
  animation: pulse 2s ease-in-out infinite;
}

/* 状态颜色工具类 */
.text-primary { color: var(--primary); }
.text-accent { color: var(--accent); }
.text-success { color: var(--success); }
.text-warning { color: var(--warning); }
.text-error { color: var(--error); }
.text-muted { color: var(--text-muted); }
.text-subtle { color: var(--text-subtle); }

.bg-primary { background-color: var(--primary); }
.bg-primary-light { background-color: var(--primary-light); }
.bg-subtle { background-color: var(--card-soft); }

/* =========================
   2025-12 Site Refresh
   - System font stack (no external font loading)
   - Tighter spacing scale and calmer shadows/motion
   - Unified header/footer + blog typography
   ========================= */

:root {
  --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, Arial, "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", "Noto Sans SC",
    "Source Han Sans SC", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono",
    "Courier New", monospace;

  --shell-width: 1120px;

  --radius-sm: 10px;
  --radius-md: 14px;
  --radius-lg: 18px;

  --shadow-1: 0 1px 2px rgba(15, 23, 42, 0.06), 0 0 0 1px rgba(15, 23, 42, 0.04);
  --shadow-2: 0 10px 22px rgba(15, 23, 42, 0.08), 0 0 0 1px rgba(15, 23, 42, 0.04);
  --shadow-3: 0 18px 42px rgba(15, 23, 42, 0.12), 0 0 0 1px rgba(15, 23, 42, 0.05);

  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --dur-1: 120ms;
  --dur-2: 200ms;
  --dur-3: 320ms;

  --ring: 0 0 0 4px rgba(37, 99, 235, 0.22);
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  background: linear-gradient(180deg, #f8fafc 0%, #ffffff 60%, #f8fafc 100%);
}

code,
pre,
kbd,
samp {
  font-family: var(--font-mono);
}

.shell {
  max-width: var(--shell-width);
  padding-left: clamp(16px, 3vw, 28px);
  padding-right: clamp(16px, 3vw, 28px);
}

/* Focus + selection */
:focus-visible {
  outline: none;
  box-shadow: var(--ring);
  border-radius: 10px;
}

::selection {
  background: rgba(37, 99, 235, 0.18);
}

/* Calm down global animations */
.animate-pulse,
.animate-float {
  animation: none !important;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto !important;
  }
  * {
    animation: none !important;
    transition: none !important;
  }
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: blur(14px) saturate(160%);
  -webkit-backdrop-filter: blur(14px) saturate(160%);
  border-bottom: 1px solid rgba(226, 232, 240, 0.8);
}

.site-header.scrolled {
  background: rgba(255, 255, 255, 0.9);
}

.brand {
  gap: 10px;
}

.brand-mark {
  box-shadow: var(--shadow-1);
}

.nav ul {
  gap: 10px;
}

.nav a {
  border-radius: 10px;
  transition: background var(--dur-2) var(--ease-out), color var(--dur-2) var(--ease-out);
}

.nav a:hover {
  text-decoration: none;
  background: rgba(37, 99, 235, 0.08);
}

.nav a.active {
  background: rgba(37, 99, 235, 0.12);
}

.nav-toggle {
  border-radius: 12px;
  transition: transform var(--dur-2) var(--ease-out), background var(--dur-2) var(--ease-out);
}

.nav-toggle:active {
  transform: scale(0.98);
}

.nav .dropdown-menu {
  box-shadow: var(--shadow-2);
  border-radius: var(--radius-md);
  border: 1px solid rgba(226, 232, 240, 0.9);
}

/* Buttons */
.btn {
  border-radius: 14px;
  padding: 0.7rem 1rem;
  min-height: 44px;
  transition: transform var(--dur-2) var(--ease-out), box-shadow var(--dur-2) var(--ease-out),
    background var(--dur-2) var(--ease-out), border-color var(--dur-2) var(--ease-out);
}

.btn:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-2);
  text-decoration: none;
}

.btn:active {
  transform: translateY(0);
  box-shadow: var(--shadow-1);
}

.btn.ghost:hover {
  background: rgba(2, 6, 23, 0.04);
}

/* Cards */
.card,
.panel,
.cta-card,
.article-card,
.service-card {
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-1);
}

.card:hover,
.article-card:hover {
  box-shadow: var(--shadow-2);
  transform: translateY(-2px);
}

/* Section rhythm */
.section {
  padding: clamp(44px, 5vw, 76px) 0;
}

.hero {
  padding: clamp(44px, 6vw, 92px) 0;
}

.stack {
  gap: clamp(18px, 3vw, 28px);
}

.split {
  gap: clamp(16px, 3vw, 28px);
}

/* Blog article typography */
.page-post .article-shell {
  padding: clamp(30px, 4vw, 54px) 0;
}

.page-post .hero.hero-article {
  padding: clamp(20px, 3vw, 40px) 0 clamp(14px, 2vw, 24px);
}

.page-post .hero.hero-article .shell {
  display: block;
  max-width: 78ch;
}

.page-post .hero.hero-article .eyebrow {
  text-transform: none;
}

.page-post .hero.hero-article h1 {
  font-size: clamp(1.9rem, 3.2vw, 2.6rem);
  margin: 0.4rem 0 0.65rem;
}

.page-post .hero.hero-article .lede {
  margin-bottom: 0.9rem;
  font-size: 1.05rem;
  line-height: 1.7;
  max-width: none;
}

.page-post .hero.hero-article .meta-row {
  gap: 0.5rem 1rem;
  font-size: 0.95rem;
}

.page-post .hero.hero-article .tag-row {
  margin-top: 0.55rem;
}

.page-post .article-body {
  max-width: 78ch;
  margin: 0 auto;
  font-size: 1.06rem;
  line-height: 1.82;
}

.page-post .article-body > :first-child {
  margin-top: 0 !important;
}

.page-post .article-body h1 {
  font-size: clamp(1.8rem, 3.2vw, 2.3rem);
  margin: 0 0 1rem;
}

.page-post .article-body h2 {
  margin-top: 2.2rem;
  padding-top: 0.2rem;
  font-size: 1.55rem;
}

.page-post .article-body h3 {
  margin-top: 1.6rem;
  font-size: 1.25rem;
}

.page-post .article-body p,
.page-post .article-body li {
  color: #0f172a;
}

.page-post .article-body a {
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}

.page-post .article-body blockquote {
  border-left-color: rgba(37, 99, 235, 0.9);
  box-shadow: var(--shadow-1);
}

.page-post .article-body pre {
  box-shadow: var(--shadow-1);
}

.page-post .article-body table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  overflow: hidden;
  border-radius: var(--radius-md);
  border: 1px solid rgba(226, 232, 240, 0.95);
  box-shadow: var(--shadow-1);
  margin: 1.25rem 0;
}

.page-post .article-body th,
.page-post .article-body td {
  padding: 0.75rem 0.9rem;
  border-bottom: 1px solid rgba(226, 232, 240, 0.9);
  vertical-align: top;
}

.page-post .article-body th {
  background: rgba(241, 245, 249, 0.9);
  font-weight: 600;
}

.page-post .article-body tr:last-child td {
  border-bottom: 0;
}

.page-post .article-body img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-1);
}
.bg-white { background-color: #ffffff; }

/* 边框工具类 */
.border { border: 1px solid var(--border); }
.border-light { border: 1px solid var(--border-light); }
.border-primary { border-color: var(--primary); }
.border-top { border-top: 1px solid var(--border); }
.border-bottom { border-bottom: 1px solid var(--border); }

/* 间距工具类 */
.m-0 { margin: 0; }
.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.mx-auto { margin-left: auto; margin-right: auto; }

.p-0 { padding: 0; }
.pt-sm { padding-top: var(--space-sm); }
.pb-sm { padding-bottom: var(--space-sm); }
.px-md { padding-left: var(--space-md); padding-right: var(--space-md); }
.py-lg { padding-top: var(--space-lg); padding-bottom: var(--space-lg); }

/* 显示工具类 */
.block { display: block; }
.inline-block { display: inline-block; }
.inline { display: inline; }
.flex { display: flex; }
.hidden { display: none; }

/* 位置工具类 */
.relative { position: relative; }
.absolute { position: absolute; }
.fixed { position: fixed; }
.sticky { position: sticky; }

/* 过渡效果 */
.transition { transition: all var(--transition-base); }
.transition-fast { transition: all var(--transition-fast); }
.transition-slow { transition: all var(--transition-slow); }

/* 深色模式支持准备 */
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f172a;
    --bg-subtle: #1e293b;
    --panel: #1e293b;
    --card: #1e293b;
    --card-soft: #334155;
    --card-hover: #475569;
    --border: #334155;
    --border-light: #475569;
    --text: #f1f5f9;
    --text-muted: #94a3b8;
    --text-subtle: #64748b;
  }
}

/* 打印样式 */
@media print {
  .nav,
  .footer,
  .btn,
  .cta {
    display: none !important;
  }

  body {
    font-size: 12pt;
    line-height: 1.5;
  }

  a {
    color: #000 !important;
    text-decoration: underline;
  }

  .card {
    border: 1px solid #000;
    box-shadow: none;
    break-inside: avoid;
  }
}