```css
/* =========================================
   51漫画 - 完整样式表
   设计原则：高对比度、圆润友好、响应式
   ========================================= */

/* ---------- CSS变量与主题系统 ---------- */
:root {
  --color-bg: #f7f9fc;
  --color-surface: #ffffff;
  --color-surface-hover: #f0f5fa;
  --color-border: #dce3ec;
  --color-border-light: #e8edf3;
  --color-text-primary: #1a2b3c;
  --color-text-secondary: #2c3e50;
  --color-text-muted: #4a5c6e;
  --color-heading: #0f1e2d;
  --color-link: #1e4a7a;
  --color-accent: #2b5f8a;
  --color-accent-light: #e8f0f8;
  --color-button-bg: #1e3b5e;
  --color-button-text: #ffffff;
  --color-nav-bg: #ffffffcc;
  --color-footer-bg: #1f2e3c;
  --color-footer-text: #e2e8f0;
  --color-footer-heading: #ffffff;
  --color-footer-border: #3b4b5a;
  --color-code-bg: #edf2f7;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.08);
  --radius: 16px;
  --radius-lg: 24px;
  --radius-sm: 10px;
  --transition: all 0.25s ease;
  --gradient-banner: linear-gradient(135deg, #1f3a5f, #2b5f8a);
  --gradient-banner-alt: linear-gradient(135deg, #2a4d69, #4f7a9e);
  --gradient-accent: linear-gradient(135deg, #1e3b5e, #2b5f8a);
  --max-width: 1280px;
}

[data-theme="dark"] {
  --color-bg: #121a24;
  --color-surface: #1e2a36;
  --color-surface-hover: #253545;
  --color-border: #2d3e4e;
  --color-border-light: #34485a;
  --color-text-primary: #e2e8f0;
  --color-text-secondary: #cbd5e1;
  --color-text-muted: #94a3b8;
  --color-heading: #ffffff;
  --color-link: #7ab0e0;
  --color-accent: #8bb4dd;
  --color-accent-light: #2a3d4d;
  --color-button-bg: #3b5c7a;
  --color-button-text: #ffffff;
  --color-nav-bg: #1e2a36cc;
  --color-footer-bg: #0c131c;
  --color-footer-text: #cbd5e1;
  --color-footer-heading: #f1f5f9;
  --color-footer-border: #2a3b4a;
  --color-code-bg: #2a3744;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.4);
  --gradient-banner: linear-gradient(135deg, #0f1e2d, #1e3b5e);
  --gradient-banner-alt: linear-gradient(135deg, #1a2b3c, #2b5f8a);
  --gradient-accent: linear-gradient(135deg, #2b5f8a, #4a7aa5);
}

/* ---------- 基础重置与排版 ---------- */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'Noto Sans', sans-serif;
  background-color: var(--color-bg);
  color: var(--color-text-primary);
  line-height: 1.6;
  font-size: 16px;
  transition: background-color 0.25s ease, color 0.25s ease;
  overflow-x: hidden;
}

img,
svg {
  max-width: 100%;
  display: block;
}

a {
  color: var(--color-link);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease;
}

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

h1,
h2,
h3,
h4,
h5 {
  color: var(--color-heading);
  line-height: 1.3;
  font-weight: 700;
}

h1 {
  font-size: 2.4rem;
}

h2 {
  font-size: 2rem;
}

h3 {
  font-size: 1.4rem;
}

p {
  margin-bottom: 0.8rem;
}

ul,
ol {
  padding-left: 1.5rem;
  margin-bottom: 1rem;
}

li {
  margin-bottom: 0.4rem;
}

/* ---------- 通用工具类 ---------- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1.5rem 2rem;
  width: 100%;
}

.section-padding {
  padding: 2.5rem 0;
}

.section-title {
  font-size: 2.2rem;
  color: var(--color-heading);
  margin: 2.5rem 0 1.5rem;
  border-left: 6px solid var(--color-accent);
  padding-left: 1.2rem;
  position: relative;
  letter-spacing: -0.02em;
}

.section-subtitle {
  font-size: 1.2rem;
  color: var(--color-text-secondary);
  margin-bottom: 1.5rem;
  font-weight: 400;
}

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

.text-center {
  text-align: center;
}

/* 滚动条美化 */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--color-bg);
}

::-webkit-scrollbar-thumb {
  background: var(--color-border);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-accent);
}

/* 选中文本 */
::selection {
  background-color: var(--color-accent);
  color: #ffffff;
}

/* 按钮 */
.btn {
  background: var(--color-button-bg);
  color: var(--color-button-text);
  padding: 0.6rem 1.6rem;
  border-radius: 40px;
  border: none;
  font-weight: 600;
  display: inline-block;
  cursor: pointer;
  transition: var(--transition);
  font-size: 0.95rem;
}

.btn:hover {
  opacity: 0.9;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  text-decoration: none;
}

.btn-outline {
  background: transparent;
  border: 2px solid var(--color-accent);
  color: var(--color-accent);
}

.btn-outline:hover {
  background: var(--color-accent);
  color: #ffffff;
}

/* ---------- 吸顶导航 ---------- */
.sticky-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--color-nav-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--color-border);
  transition: background-color 0.3s ease;
}

.nav-container {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.8rem 2rem;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.logo {
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--color-heading);
  letter-spacing: -0.5px;
  line-height: 1.2;
  cursor: pointer;
  transition: opacity 0.2s;
}

.logo:hover {
  opacity: 0.85;
}

.logo span {
  color: var(--color-accent);
}

.nav-links {
  display: flex;
  gap: 1.8rem;
  font-weight: 500;
  flex-wrap: wrap;
}

.nav-links a {
  color: var(--color-text-primary);
  padding: 0.4rem 0;
  border-bottom: 2px solid transparent;
  transition: border-color 0.2s ease, color 0.2s ease;
  font-size: 0.95rem;
}

.nav-links a:hover {
  border-bottom-color: var(--color-accent);
  color: var(--color-heading);
  text-decoration: none;
}

.menu-toggle {
  display: none;
  background: none;
  border: 1px solid var(--color-border);
  padding: 0.4rem 0.8rem;
  border-radius: 8px;
  color: var(--color-text-primary);
  font-size: 1.2rem;
  cursor: pointer;
  transition: var(--transition);
  line-height: 1;
}

.menu-toggle:hover {
  background: var(--color-surface);
}

.search-box {
  display: flex;
  align-items: center;
  gap: 0.3rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  padding: 0.25rem 0.8rem;
  border-radius: 40px;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.search-box:focus-within {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(43, 95, 138, 0.1);
}

.search-box input {
  border: none;
  background: transparent;
  padding: 0.35rem 0.2rem;
  color: var(--color-text-primary);
  outline: none;
  width: 110px;
  font-size: 0.9rem;
  transition: width 0.3s ease;
}

.search-box input::placeholder {
  color: var(--color-text-muted);
}

.search-box input:focus {
  width: 150px;
}

.search-box button {
  background: none;
  border: none;
  color: var(--color-text-primary);
  cursor: pointer;
  font-size: 1rem;
  padding: 0.2rem;
  display: flex;
  align-items: center;
  transition: color 0.2s;
}

.search-box button:hover {
  color: var(--color-accent);
}

.dark-toggle {
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: 30px;
  padding: 0.3rem 1rem;
  color: var(--color-text-primary);
  cursor: pointer;
  font-size: 0.85rem;
  transition: var(--transition);
  white-space: nowrap;
}

.dark-toggle:hover {
  background: var(--color-surface);
  border-color: var(--color-accent);
}

/* ---------- Banner轮播 ---------- */
.banner-carousel {
  display: flex;
  gap: 1.2rem;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  padding: 1rem 0 2rem;
  margin-bottom: 1.5rem;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.banner-carousel::-webkit-scrollbar {
  display: none;
}

.banner-slide {
  min-width: 85%;
  background: var(--gradient-banner);
  border-radius: var(--radius-lg);
  padding: 2.5rem 3rem;
  color: white;
  scroll-snap-align: start;
  box-shadow: var(--shadow-lg);
  display: flex;
  flex-direction: column;
  justify-content: center;
  position: relative;
  overflow: hidden;
  transition: transform 0.3s ease;
  min-height: 220px;
}

.banner-slide::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 300px;
  height: 300px;
  background: radial-gradient(circle, rgba(255,255,255,0.15) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

.banner-slide:hover {
  transform: scale(1.01);
}

.banner-slide h2 {
  font-size: 2.2rem;
  color: #ffffff;
  margin-bottom: 0.5rem;
  position: relative;
  z-index: 1;
  text-shadow: 0 2px 8px rgba(0,0,0,0.2);
}

.banner-slide p {
  font-size: 1.15rem;
  max-width: 70%;
  color: #f0f5fa;
  position: relative;
  z-index: 1;
  line-height: 1.5;
}

.banner-slide:nth-child(2) {
  background: var(--gradient-banner-alt);
}

/* 轮播指示器（用CSS模拟） */
.banner-carousel::after {
  content: '← 滑动浏览 →';
  display: block;
  text-align: center;
  color: var(--color-text-muted);
  font-size: 0.8rem;
  padding: 0.8rem 0;
  letter-spacing: 0.1em;
}

/* ---------- 卡片网格 ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
  margin: 2.5rem 0;
}

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-accent);
}

.card h3 {
  color: var(--color-heading);
  font-size: 1.3rem;
  margin-bottom: 0.5rem;
  position: relative;
  padding-bottom: 0.5rem;
}

.card h3::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 32px;
  height: 3px;
  background: var(--color-accent);
  border-radius: 3px;
}

.card p {
  color: var(--color-text-secondary);
  flex-grow: 1;
  font-size: 0.95rem;
}

.card .meta,
.article-meta {
  color: var(--color-text-muted);
  font-size: 0.85rem;
  display: block;
  margin-top: 0.5rem;
  font-weight: 400;
}

/* ---------- 品牌介绍区域 ---------- */
.brand-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

.brand-card {
  background: var(--color-surface);
  padding: 1.8rem;
  border-radius: 20px;
  border: 1px solid var(--color-border);
  transition: var(--transition);
}

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

.brand-card h3 {
  color: var(--color-heading);
  margin-bottom: 1rem;
  font-size: 1.5rem;
}

.brand-card p {
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* ---------- 解决方案区域 ---------- */
.solution-flex {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.solution-item {
  flex: 1;
  min-width: 260px;
  background: var(--color-surface);
  padding: 1.8rem;
  border-radius: 20px;
  border: 1px solid var(--color-border);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.solution-item::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: var(--gradient-accent);
  opacity: 0;
  transition: opacity 0.3s;
}

.solution-item:hover::before {
  opacity: 1;
}

.solution-item:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}

.solution-item h4 {
  color: var(--color-heading);
  margin-bottom: 0.8rem;
  font-size: 1.2rem;
}

.solution-item p {
  color: var(--color-text-secondary);
  font-size: 0.95rem;
}

/* ---------- 文章列表 ---------- */
.article-list {
  display: flex;
  flex-direction: column;
  gap: 1.2rem;
  margin: 2rem 0;
}

.article-item {
  background: var(--color-surface);
  border-radius: var(--radius);
  padding: 1.5rem 2rem;
  border-left: 5px solid var(--color-accent);
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  position: relative;
}

.article-item:hover {
  transform: translateX(6px);
  box-shadow: var(--shadow-md);
  border-left-color: var(--color-link);
}

.article-item h3 {
  font-size: 1.4rem;
  color: var(--color-heading);
  margin-bottom: 0.5rem;
  transition: color 0.2s;
}

.article-item:hover h3 {
  color: var(--color-accent);
}

.article-item .article-meta {
  margin-bottom: 0.8rem;
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

.article-item p {
  margin-top: 0.5rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

.read-more {
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  margin-top: 0.3rem;
  transition: gap 0.2s ease;
}

.read-more:hover {
  gap: 0.6rem;
}

/* ---------- HowTo区域 ---------- */
.howto-container {
  background: var(--color-surface);
  padding: 2.5rem;
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}

.howto-container h3 {
  color: var(--color-heading);
  margin: 1.5rem 0 0.5rem;
  font-size: 1.3rem;
  position: relative;
  display: inline-block;
}

.howto-container h3::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--color-accent);
  border-radius: 2px;
}

.howto-container p,
.howto-container li {
  color: var(--color-text-secondary);
}

.howto-container ol {
  padding-left: 1.8rem;
}

.howto-container ol li {
  margin-bottom: 0.6rem;
  padding-left: 0.3rem;
}

/* ---------- FAQ区域 ---------- */
.faq-section {
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
}

.faq-section details {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 14px;
  padding: 1rem 1.8rem;
  transition: var(--transition);
  cursor: pointer;
}

.faq-section details:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-sm);
}

.faq-section details[open] {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-sm);
}

.faq-section summary {
  font-weight: 600;
  color: var(--color-heading);
  cursor: pointer;
  font-size: 1.05rem;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.5rem;
}

.faq-section summary::-webkit-details-marker {
  display: none;
}

.faq-section summary::after {
  content: '＋';
  font-size: 1.2rem;
  color: var(--color-accent);
  transition: transform 0.3s ease;
  font-weight: 400;
}

.faq-section details[open] summary::after {
  content: '－';
  transform: rotate(180deg);
}

.faq-section details p {
  margin-top: 0.8rem;
  color: var(--color-text-secondary);
  padding-top: 0.8rem;
  border-top: 1px solid var(--color-border-light);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* ---------- 表格样式 ---------- */
.table-wrapper {
  overflow-x: auto;
  margin: 2rem 0;
  border-radius: 12px;
  box-shadow: var(--shadow-sm);
}

table {
  width: 100%;
  border-collapse: collapse;
  background: var(--color-surface);
  border-radius: 12px;
  overflow: hidden;
}

th {
  background: var(--color-code-bg);
  color: var(--color-heading);
  font-weight: 700;
  text-align: left;
  padding: 0.9rem 1.2rem;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

td {
  border-top: 1px solid var(--color-border);
  padding: 0.9rem 1.2rem;
  color: var(--color-text-primary);
  font-size: 0.95rem;
}

tbody tr:hover {
  background: var(--color-surface-hover);
}

/* ---------- 联系区域 ---------- */
.contact-section {
  background: var(--color-surface);
  padding: 2.5rem;
  border-radius: 28px;
  margin: 2rem 0;
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}

.contact-section p {
  margin-bottom: 0.6rem;
  color: var(--color-text-secondary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.contact-section strong {
  color: var(--color-heading);
}

.badge-row {
  display: flex;
  gap: 0.8rem;
  flex-wrap: wrap;
  margin-top: 1.2rem;
}

.badge-row span {
  background: var(--color-accent-light);
  color: var(--color-accent);
  padding: 0.3rem 0.8rem;
  border-radius: 30px;
  font-size: 0.85rem;
  font-weight: 500;
  border: 1px solid transparent;
  transition: var(--transition);
}

.badge-row span:hover {
  border-color: var(--color-accent);
  transform: translateY(-2px);
}

/* ---------- 页脚 ---------- */
.site-footer {
  background: var(--color-footer-bg);
  color: var(--color-footer-text);
  margin-top: 3rem;
  padding: 3rem 2rem 1.5rem;
  border-radius: 24px 24px 0 0;
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 2.5rem;
  max-width: var(--max-width);
  margin: 0 auto;
}

.site-footer h4,
.site-footer h5 {
  color: var(--color-footer-heading);
  margin-bottom: 1rem;
  font-size: 1.1rem;
  position: relative;
  padding-bottom: 0.5rem;
}

.site-footer h5::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 30px;
  height: 2px;
  background: var(--color-accent);
  border-radius: 2px;
}

.site-footer ul {
  list-style: none;
  padding: 0;
}

.site-footer ul li {
  margin-bottom: 0.4rem;
}

.site-footer a {
  color: #cbd5e1;
  transition: color 0.2s ease, padding-left 0.2s ease;
  font-weight: 400;
}

.site-footer a:hover {
  color: #ffffff;
  padding-left: 4px;
  text-decoration: none;
}

.copyright {
  border-top: 1px solid var(--color-footer-border);
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  text-align: center;
  color: #b0c4d9;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  font-size: 0.9rem;
}

.copyright p {
  margin-bottom: 0.3rem;
}

/* ---------- 返回顶部按钮 ---------- */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  background: var(--color-button-bg);
  color: #ffffff;
  padding: 0.8rem 1.2rem;
  border-radius: 40px;
  border: none;
  cursor: pointer;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
  z-index: 200;
  font-size: 0.9rem;
  font-weight: 600;
  transition: var(--transition);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.back-to-top.show {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.back-to-top:hover {
  transform: translateY(-4px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
  background: var(--color-accent);
}

/* ---------- 暗色切换按钮状态 ---------- */
.dark-toggle[data-state="dark"] {
  background: var(--color-accent);
  color: #ffffff;
  border-color: var(--color-accent);
}

/* ---------- 滚动动画 ---------- */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.95);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

/* 为需要动画的元素添加初始状态 */
.card,
.article-item,
.faq-section details,
.solution-item,
.brand-card,
.banner-slide,
.contact-section {
  animation: fadeInUp 0.6s ease forwards;
  opacity: 0;
}

/* 交错延迟 */
.card:nth-child(1),
.solution-item:nth-child(1),
.brand-card:nth-child(1) {
  animation-delay: 0.1s;
}

.card:nth-child(2),
.solution-item:nth-child(2),
.brand-card:nth-child(2) {
  animation-delay: 0.2s;
}

.card:nth-child(3),
.solution-item:nth-child(3),
.brand-card:nth-child(3) {
  animation-delay: 0.3s;
}

.card:nth-child(4),
.solution-item:nth-child(4),
.brand-card:nth-child(4) {
  animation-delay: 0.4s;
}

.card:nth-child(5),
.solution-item:nth-child(5),
.brand-card:nth-child(5) {
  animation-delay: 0.5s;
}

.card:nth-child(6),
.solution-item:nth-child(6),
.brand-card:nth-child(6) {
  animation-delay: 0.6s;
}

.article-item:nth-child(1) { animation-delay: 0.1s; }
.article-item:nth-child(2) { animation-delay: 0.15s; }
.article-item:nth-child(3) { animation-delay: 0.2s; }
.article-item:nth-child(4) { animation-delay: 0.25s; }
.article-item:nth-child(5) { animation-delay: 0.3s; }
.article-item:nth-child(6) { animation-delay: 0.35s; }
.article-item:nth-child(7) { animation-delay: 0.4s; }
.article-item:nth-child(8) { animation-delay: 0.45s; }
.article-item:nth-child(9) { animation-delay: 0.5s; }
.article-item:nth-child(10) { animation-delay: 0.55s; }

.faq-section details:nth-child(1) { animation-delay: 0.05s; }
.faq-section details:nth-child(2) { animation-delay: 0.1s; }
.faq-section details:nth-child(3) { animation-delay: 0.15s; }
.faq-section details:nth-child(4) { animation-delay: 0.2s; }
.faq-section details:nth-child(5) { animation-delay: 0.25s; }
.faq-section details:nth-child(6) { animation-delay: 0.3s; }
.faq-section details:nth-child(7) { animation-delay: 0.35s; }
.faq-section details:nth-child(8) { animation-delay: 0.4s; }
.faq-section details:nth-child(9) { animation-delay: 0.45s; }
.faq-section details:nth-child(10) { animation-delay: 0.5s; }
.faq-section details:nth-child(11) { animation-delay: 0.55s; }
.faq-section details:nth-child(12) { animation-delay: 0.6s; }
.faq-section details:nth-child(13) { animation-delay: 0.65s; }
.faq-section details:nth-child(14) { animation-delay: 0.7s; }
.faq-section details:nth-child(15) { animation-delay: 0.75s; }

/* 尊重减少动画偏好 */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  html {
    scroll-behavior: auto;
  }
}

/* ---------- 响应式设计 ---------- */
@media (max-width: 1024px) {
  .container {
    padding: 1.5rem;
  }

  .nav-container {
    padding: 0.8rem 1.5rem;
  }

  .banner-slide {
    min-width: 90%;
    padding: 2rem;
  }

  .banner-slide h2 {
    font-size: 1.8rem;
  }

  .banner-slide p {
    max-width: 85%;
  }

  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.8rem;
  }

  .section-title {
    font-size: 1.8rem;
  }
}

@media (max-width: 800px) {
  .nav-links {
    display: none;
    width: 100%;
    flex-direction: column;
    gap: 0.8rem;
    padding: 1rem 0;
    border-top: 1px solid var(--color-border);
  }

  .nav-links.show {
    display: flex;
  }

  .menu-toggle {
    display: block;
  }

  .banner-slide p {
    max-width: 100%;
  }

  .banner-slide {
    min-width: 95%;
    padding: 1.8rem;
    min-height: 180px;
  }

  .banner-slide h2 {
    font-size: 1.6rem;
  }

  .banner-slide p {
    font-size: 1rem;
  }

  .search-box input {
    width: 80px;
  }

  .search-box input:focus {
    width: 120px;
  }

  .container {
    padding: 1rem;
  }

  .article-item {
    padding: 1.2rem 1.5rem;
  }

  .article-item h3 {
    font-size: 1.2rem;
  }

  .howto-container {
    padding: 1.5rem;
  }

  .contact-section {
    padding: 1.5rem;
  }

  .site-footer {
    padding: 2rem 1.5rem 1.5rem;
  }

  .footer-cols {
    gap: 1.5rem;
  }

  .back-to-top {
    bottom: 1.2rem;
    right: 1.2rem;
    padding: 0.6rem 1rem;
  }
}

@media (max-width: 480px) {
  .logo {
    font-size: 1.5rem;
  }

  .nav-container {
    gap: 0.3rem;
  }

  .dark-toggle {
    padding: 0.25rem 0.6rem;
    font-size: 0.75rem;
  }

  .search-box {
    display: none;
  }

  .banner-slide {
    min-width: 100%;
    padding: 1.5rem;
  }

  .banner-slide h2 {
    font-size: 1.4rem;
  }

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

  .section-title {
    font-size: 1.5rem;
    margin: 2rem 0 1rem;
  }

  .article-item {
    padding: 1rem 1.2rem;
  }

  .article-item h3 {
    font-size: 1.1rem;
  }

  .howto-container,
  .contact-section {
    padding: 1.2rem;
    border-radius: 16px;
  }

  .footer-cols {
    grid-template-columns: 1fr 1fr;
  }

  .copyright {
    font-size: 0.8rem;
  }
}

/* ---------- 打印样式 ---------- */
@media print {
  .sticky-header,
  .banner-carousel,
  .back-to-top,
  .dark-toggle,
  .menu-toggle,
  .search-box {
    display: none !important;
  }

  body {
    background: #ffffff;
    color: #000000;
  }

  .container {
    max-width: 100%;
    padding: 0;
  }

  .card,
  .article-item,
  .faq-section details,
  .solution-item,
  .brand-card,
  .contact-section {
    box-shadow: none;
    border: 1px solid #ddd;
    animation: none;
    opacity: 1;
  }

  a {
    color: #000000;
  }

  .site-footer {
    background: #ffffff;
    color: #000000;
    border-top: 2px solid #000000;
  }
}

/* ---------- 无障碍辅助 ---------- */
.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;
}

/* 焦点可见性 */
:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: 4px;
}

/* 键盘导航用户 */
body.keyboard-nav a:focus,
body.keyboard-nav button:focus {
  outline: 3px solid var(--color-accent);
  outline-offset: 2px;
}

/* 链接下划线动画 */
.inline-link {
  position: relative;
}

.inline-link::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1px;
  background: currentColor;
  transition: width 0.3s ease;
}

.inline-link:hover::after {
  width: 100%;
}
```