/* ============================================================
   BASE — 基础变量、重置与全局排版
   ============================================================ */
:root {
  --color-primary: #111827;
  --color-accent: #ef4444;
  --color-bg-section: #f3f4f6;
  --color-bg-card: #ffffff;
  --color-text-secondary: #6b7280;
  --color-border: #e5e7eb;
  --color-text: #111827;
  --container-width: 1200px;
  --radius-card: 8px;
  --radius-small: 4px;
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --header-height: 72px;
  --transition-base: 0.2s ease;
}

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

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

body {
  font-family: var(--font-family);
  font-size: 16px;
  line-height: 1.7;
  color: var(--color-text);
  background-color: #ffffff;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-base);
}

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

ul,
ol {
  list-style: none;
}

table {
  border-collapse: collapse;
  width: 100%;
}

/* ============================================================
   LAYOUT — 全站通栏容器与页面骨架
   ============================================================ */
.site-body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.site-main {
  flex: 1 0 auto;
}

/* 首页主内容区 */
.home-main {
  width: 100%;
}

/* 内页主内容区 */
.inner-main {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px 64px;
}

/* ============================================================
   HEADER — 全站统一页头与导航
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--color-bg-card);
  border-bottom: 1px solid var(--color-border);
}

.header-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
  height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  flex-shrink: 0;
}

.brand-link {
  display: inline-flex;
  align-items: center;
  font-size: 22px;
  font-weight: 700;
  color: var(--color-primary);
  letter-spacing: 0;
}

.brand-link:hover {
  color: var(--color-accent);
}

.brand-name {
  line-height: 1.2;
}

/* 桌面端导航 */
.site-nav {
  display: block;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-item {
  position: relative;
}

.nav-link {
  display: block;
  padding: 10px 16px;
  font-size: 15px;
  font-weight: 500;
  color: var(--color-primary);
  border-radius: var(--radius-small);
  transition: background-color var(--transition-base), color var(--transition-base);
}

.nav-link:hover {
  color: var(--color-accent);
  background-color: var(--color-bg-section);
}

.nav-link.is-current {
  color: var(--color-accent);
  font-weight: 600;
  background-color: rgba(239, 68, 68, 0.06);
}

/* 移动端汉堡按钮 */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 44px;
  height: 44px;
  padding: 0;
  border: none;
  background: transparent;
  cursor: pointer;
  gap: 5px;
}

.nav-toggle-line {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--color-primary);
  border-radius: 1px;
  transition: transform var(--transition-base), opacity var(--transition-base);
}

/* ============================================================
   FOOTER — 全站统一页脚
   ============================================================ */
.site-footer {
  background-color: var(--color-bg-section);
  border-top: 1px solid var(--color-border);
  margin-top: auto;
}

.footer-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 48px 24px 32px;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 40px;
}

.footer-brand .footer-slogan {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 12px;
}

.footer-desc {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

.footer-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 16px;
}

.footer-links li {
  margin-bottom: 10px;
}

.footer-links a {
  font-size: 14px;
  color: var(--color-text-secondary);
}

.footer-links a:hover {
  color: var(--color-accent);
}

.footer-note {
  margin-top: 16px;
  font-size: 13px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

.footer-bottom {
  border-top: 1px solid var(--color-border);
  padding: 20px 24px;
  text-align: center;
}

.footer-bottom p {
  font-size: 13px;
  color: var(--color-text-secondary);
  max-width: var(--container-width);
  margin: 0 auto;
}

/* ============================================================
   COMPONENTS — 通用组件
   ============================================================ */
/* 区块标题 */
.section-heading,
.section-head {
  margin-bottom: 32px;
}

.section-title {
  font-size: 22px;
  font-weight: 700;
  color: var(--color-primary);
  line-height: 1.4;
  margin-bottom: 8px;
}

.section-desc {
  font-size: 15px;
  color: var(--color-text-secondary);
  max-width: 720px;
  line-height: 1.7;
}

/* 图标色块 */
.icon-block {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-small);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: 700;
  color: #ffffff;
  background-color: var(--color-primary);
  flex-shrink: 0;
}

.icon-block-red {
  background-color: var(--color-accent);
}

.icon-block-dark {
  background-color: var(--color-primary);
}

.icon-block-gray {
  background-color: var(--color-text-secondary);
}

.icon-block-light {
  background-color: var(--color-bg-section);
  color: var(--color-primary);
  border: 1px solid var(--color-border);
}

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-small);
  line-height: 1.4;
  min-height: 44px;
  transition: background-color var(--transition-base), color var(--transition-base), border-color var(--transition-base);
}

.btn-primary {
  background-color: var(--color-accent);
  color: #ffffff;
  border: 1px solid var(--color-accent);
}

.btn-primary:hover {
  background-color: #dc2626;
  border-color: #dc2626;
  color: #ffffff;
}

.btn-secondary {
  background-color: var(--color-bg-card);
  color: var(--color-primary);
  border: 1px solid var(--color-border);
}

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

/* 卡片链接 */
.card-link {
  display: inline-flex;
  align-items: center;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-accent);
  margin-top: auto;
}

.card-link:hover {
  color: #dc2626;
}

/* 图片容器 */
figure {
  margin: 0;
}

figcaption {
  font-size: 13px;
  color: var(--color-text-secondary);
  line-height: 1.6;
  margin-top: 8px;
}

/* 通用链接入口 */
.section-link {
  display: inline-flex;
  align-items: center;
  font-size: 15px;
  font-weight: 600;
  color: var(--color-accent);
  margin-top: 24px;
}

.section-link:hover {
  color: #dc2626;
}

/* ============================================================
   PAGE — 首页专属模块
   ============================================================ */
/* 首屏主视觉 */
.hero-section {
  position: relative;
  background-color: var(--color-primary);
  background-image: url("/assets/media/hero.webp");
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  color: #ffffff;
  padding: 88px 0;
}

.hero-section::before {
  content: "";
  position: absolute;
  inset: 0;
  background-color: rgba(17, 24, 39, 0.72);
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
}

.hero-title {
  font-size: 36px;
  font-weight: 700;
  line-height: 1.3;
  color: #ffffff;
  max-width: 640px;
  margin-bottom: 16px;
}

.hero-subtitle {
  font-size: 17px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.9);
  max-width: 560px;
  margin-bottom: 32px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.hero-actions .btn-primary {
  border-color: #ffffff;
}

.hero-actions .btn-secondary {
  background-color: transparent;
  color: #ffffff;
  border-color: rgba(255, 255, 255, 0.6);
}

.hero-actions .btn-secondary:hover {
  background-color: rgba(255, 255, 255, 0.1);
  border-color: #ffffff;
  color: #ffffff;
}

.hero-figure {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
}

.hero-image {
  display: block;
  width: 1px;
  height: 1px;
}

/* 首屏辅助图片（真实可见内容图） */
.content-media {
  margin: 0;
  padding: 0 24px;
  max-width: var(--container-width);
  margin-left: auto;
  margin-right: auto;
}

.content-media-primary {
  margin-top: 48px;
}

.content-media img {
  width: 100%;
  height: auto;
  border-radius: var(--radius-card);
}

/* 服务能力概览 */
.capability-section,
.process-overview-section,
.scenario-section,
.help-guide-section {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 64px 24px 0;
}

.capability-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.capability-card {
  background-color: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  padding: 32px 24px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.capability-card:hover {
  border-color: var(--color-accent);
  box-shadow: 0 4px 16px rgba(17, 24, 39, 0.06);
}

.capability-card h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-primary);
}

.capability-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  flex: 1;
}

/* 合作流程概览 */
.process-steps {
  display: flex;
  flex-direction: column;
  gap: 0;
  counter-reset: step-counter;
}

.process-step {
  display: flex;
  gap: 20px;
  padding: 20px 0;
  border-bottom: 1px solid var(--color-border);
  align-items: flex-start;
}

.process-step:first-child {
  padding-top: 0;
}

.process-step:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.process-step .step-number {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-small);
  background-color: var(--color-accent);
  color: #ffffff;
  font-size: 16px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  line-height: 1;
}

.process-step .step-content {
  flex: 1;
}

.process-step .step-content h3 {
  font-size: 17px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 4px;
}

.process-step .step-content p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* 问题场景入口 */
.scenario-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.scenario-card {
  background-color: var(--color-bg-section);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  padding: 32px 28px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  transition: border-color var(--transition-base);
}

.scenario-card:hover {
  border-color: var(--color-accent);
}

.scenario-card h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-primary);
}

.scenario-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  flex: 1;
}

/* 帮助与指南入口 */
.help-category-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.help-category-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 24px;
  background-color: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  transition: border-color var(--transition-base), background-color var(--transition-base);
}

.help-category-card:hover {
  border-color: var(--color-accent);
  background-color: var(--color-bg-section);
  color: var(--color-primary);
}

.help-category-card h3 {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-primary);
}

.help-category-card p {
  font-size: 13px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

/* 首页底部关联导航 */
.home-main .related-links {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 48px 24px 64px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 24px;
}

.related-links-label {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-text-secondary);
}

.related-links-item {
  font-size: 14px;
  color: var(--color-primary);
  padding: 6px 14px;
  border: 1px solid var(--color-border);
  border-radius: 20px;
  transition: border-color var(--transition-base), color var(--transition-base);
}

.related-links-item:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ============================================================
   PAGE — 内页通用骨架
   ============================================================ */
/* 面包屑 */
.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  padding: 20px 0 8px;
  font-size: 14px;
  color: var(--color-text-secondary);
}

.breadcrumb a {
  color: var(--color-text-secondary);
}

.breadcrumb a:hover {
  color: var(--color-accent);
}

.breadcrumb-sep {
  color: var(--color-text-secondary);
  font-size: 13px;
}

.breadcrumb-current {
  color: var(--color-primary);
  font-weight: 500;
}

/* 页面标题区 */
.page-header {
  padding: 24px 0 40px;
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 48px;
}

.page-title {
  font-size: 28px;
  font-weight: 700;
  color: var(--color-primary);
  line-height: 1.3;
  margin-bottom: 12px;
}

.page-description {
  font-size: 16px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  max-width: 760px;
}

/* ============================================================
   PAGE — 服务项目页
   ============================================================ */
.service-matrix-section,
.delivery-section {
  margin-bottom: 64px;
}

.service-table-wrap {
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  background-color: var(--color-bg-card);
}

.service-matrix-table {
  min-width: 720px;
}

.service-matrix-table thead th {
  background-color: var(--color-bg-section);
  padding: 16px 20px;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-primary);
  text-align: left;
  border-bottom: 1px solid var(--color-border);
  white-space: nowrap;
}

.service-matrix-table tbody td {
  padding: 16px 20px;
  font-size: 14px;
  color: var(--color-text);
  border-bottom: 1px solid var(--color-border);
  vertical-align: top;
  line-height: 1.7;
}

.service-matrix-table tbody tr:last-child td {
  border-bottom: none;
}

.service-matrix-table tbody tr:hover {
  background-color: rgba(243, 244, 246, 0.5);
}

/* 服务交付方式 */
.delivery-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 48px;
}

.delivery-card {
  background-color: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  padding: 28px 24px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  transition: border-color var(--transition-base);
}

.delivery-card:hover {
  border-color: var(--color-accent);
}

.delivery-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--color-primary);
}

.delivery-desc {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

.service-media {
  margin-top: 8px;
}

.service-media-img {
  width: 100%;
  height: auto;
  border-radius: var(--radius-card);
}

/* 相关推荐 */
.services-related {
  margin-top: 64px;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 24px;
}

.related-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 24px;
  background-color: var(--color-bg-section);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  transition: border-color var(--transition-base);
}

.related-card:hover {
  border-color: var(--color-accent);
}

.related-card-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-primary);
}

.related-card-desc {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* ============================================================
   PAGE — 解决方案页
   ============================================================ */
.section {
  margin-bottom: 64px;
}

/* 问题现象选择 */
.issue-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.issue-card {
  background-color: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.issue-card:hover {
  border-color: var(--color-accent);
  box-shadow: 0 4px 12px rgba(17, 24, 39, 0.05);
}

.issue-card-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-primary);
}

.issue-card-desc {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  flex: 1;
}

.issue-card-link {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-accent);
}

/* 应对路径 */
.path-block {
  margin-bottom: 48px;
  padding: 32px;
  background-color: var(--color-bg-section);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
}

.path-block-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 24px;
}

.path-steps {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.path-step {
  background-color: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  padding: 20px 24px;
}

.path-step .step-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 8px;
}

.path-step .step-action,
.path-step .step-result,
.path-step .step-exception {
  font-size: 14px;
  line-height: 1.7;
  color: var(--color-text);
  margin-bottom: 6px;
}

.path-step .step-action::before {
  content: "操作：";
  font-weight: 600;
  color: var(--color-primary);
}

.path-step .step-result::before {
  content: "预期结果：";
  font-weight: 600;
  color: var(--color-primary);
}

.path-step .step-exception::before {
  content: "异常处理：";
  font-weight: 600;
  color: var(--color-accent);
}

.path-more-link {
  display: inline-flex;
  align-items: center;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-accent);
  margin-top: 20px;
}

/* 返回目录 */
.back-to-top {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 24px;
  background-color: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
}

.back-to-top-text {
  font-size: 14px;
  color: var(--color-text-secondary);
}

.back-to-top-text a {
  color: var(--color-accent);
  font-weight: 600;
}

.back-to-top-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 24px;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-primary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-small);
  min-height: 44px;
  transition: border-color var(--transition-base), color var(--transition-base);
}

.back-to-top-link:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* 配图 */
.path-figure {
  margin-top: 48px;
}

.path-image {
  width: 100%;
  height: auto;
  border-radius: var(--radius-card);
}

.path-caption {
  font-size: 13px;
  color: var(--color-text-secondary);
  margin-top: 8px;
}

/* ============================================================
   PAGE — 合作流程页
   ============================================================ */
.process-timeline-section,
.preparation-section,
.feedback-section {
  margin-bottom: 64px;
}

/* 时间轴 */
.timeline-list {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 0;
  padding-left: 0;
}

.timeline-item {
  display: flex;
  gap: 24px;
  padding: 0 0 32px;
  position: relative;
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-number {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background-color: var(--color-accent);
  color: #ffffff;
  font-size: 16px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  line-height: 1;
  position: relative;
  z-index: 1;
}

.timeline-item:not(:last-child) .timeline-number::after {
  content: "";
  position: absolute;
  top: 44px;
  left: 50%;
  transform: translateX(-50%);
  width: 2px;
  height: calc(100% + 32px);
  background-color: var(--color-border);
}

.timeline-content {
  flex: 1;
  padding-top: 4px;
}

.timeline-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 6px;
}

.timeline-text {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* 双方准备事项 */
.preparation-table-wrap {
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  background-color: var(--color-bg-card);
}

.preparation-table {
  min-width: 640px;
}

.preparation-table thead th {
  background-color: var(--color-bg-section);
  padding: 16px 20px;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-primary);
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}

.preparation-table tbody td {
  padding: 16px 20px;
  font-size: 14px;
  color: var(--color-text);
  border-bottom: 1px solid var(--color-border);
  line-height: 1.7;
  vertical-align: top;
}

.preparation-table tbody tr:last-child td {
  border-bottom: none;
}

.preparation-table tbody tr:hover {
  background-color: rgba(243, 244, 246, 0.5);
}

/* 反馈机制 */
.feedback-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.feedback-media {
  order: 1;
}

.feedback-figure {
  margin: 0;
}

.feedback-image {
  width: 100%;
  height: auto;
  border-radius: var(--radius-card);
}

.feedback-content {
  order: 2;
}

.feedback-content .section-title {
  margin-bottom: 16px;
}

.feedback-text {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 12px;
}

.feedback-text:last-child {
  margin-bottom: 0;
}

.text-link {
  color: var(--color-accent);
  font-weight: 600;
}

.text-link:hover {
  color: #dc2626;
}

/* ============================================================
   PAGE — 帮助中心页
   ============================================================ */
.help-categories,
.faq-section,
.related-guides {
  margin-bottom: 64px;
}

/* 分类目录 */
.category-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.category-card {
  background-color: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.category-card:hover {
  border-color: var(--color-accent);
  box-shadow: 0 4px 12px rgba(17, 24, 39, 0.05);
}

.category-icon {
  margin-bottom: 4px;
}

.category-name {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-primary);
}

.category-desc {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  flex: 1;
}

.category-link {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-accent);
}

/* FAQ 分组与折叠 */
.faq-group {
  margin-bottom: 40px;
}

.faq-group-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-primary);
  padding: 12px 0;
  border-bottom: 2px solid var(--color-accent);
  margin-bottom: 16px;
}

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.faq-item {
  border-bottom: 1px solid var(--color-border);
}

.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 0;
  font-size: 15px;
  font-weight: 600;
  color: var(--color-primary);
  cursor: pointer;
  list-style: none;
  transition: color var(--transition-base);
}

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

.faq-question::after {
  content: "+";
  font-size: 20px;
  font-weight: 400;
  color: var(--color-accent);
  flex-shrink: 0;
  transition: transform var(--transition-base);
}

.faq-item[open] .faq-question {
  color: var(--color-accent);
}

.faq-item[open] .faq-question::after {
  transform: rotate(45deg);
}

.faq-answer {
  padding: 0 0 20px;
}

.faq-answer p {
  font-size: 14px;
  color: var(--color-text);
  line-height: 1.8;
  margin-bottom: 8px;
}

.faq-answer p:last-child {
  margin-bottom: 0;
}

/* 帮助中心配图 */
.help-media {
  margin-bottom: 64px;
}

.media-image {
  width: 100%;
  height: auto;
  border-radius: var(--radius-card);
}

.media-caption {
  font-size: 13px;
  color: var(--color-text-secondary);
  margin-top: 8px;
}

/* 关联指南 */
.guide-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 24px;
}

.guide-card {
  background-color: var(--color-bg-section);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: border-color var(--transition-base);
}

.guide-card:hover {
  border-color: var(--color-accent);
}

.guide-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-primary);
}

.guide-text {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  flex: 1;
}

.guide-link {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-accent);
}

/* ============================================================
   PAGE — 关于我们页
   ============================================================ */
.page-layout {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 48px;
  align-items: start;
}

.layout-main {
  min-width: 0;
}

.layout-aside {
  min-width: 0;
}

.about-intro,
.about-compliance,
.about-related {
  margin-bottom: 48px;
}

.about-paragraph {
  font-size: 15px;
  color: var(--color-text);
  line-height: 1.8;
  margin-bottom: 16px;
}

.about-paragraph:last-child {
  margin-bottom: 0;
}

.about-media {
  margin-top: 24px;
}

.about-media img {
  width: 100%;
  height: auto;
  border-radius: var(--radius-card);
}

.compliance-lead {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 20px;
}

.compliance-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.compliance-item {
  background-color: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-accent);
  border-radius: var(--radius-small);
  padding: 20px 24px;
}

.compliance-item-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 6px;
}

.compliance-item-desc {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

.about-related .related-links {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 16px;
}

.related-link-item a {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-accent);
  display: inline-flex;
  align-items: center;
}

.related-link-item a:hover {
  color: #dc2626;
}

/* 侧栏服务原则 */
.aside-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-primary);
  padding-bottom: 12px;
  border-bottom: 2px solid var(--color-accent);
  margin-bottom: 20px;
}

.principles-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.principles-item {
  padding: 16px 0;
  border-bottom: 1px solid var(--color-border);
}

.principles-item:last-child {
  border-bottom: none;
}

.principles-item-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 4px;
}

.principles-item-desc {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* ============================================================
   PAGE — 404 页面
   ============================================================ */
.error-main {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 80px 24px;
}

.error-inner {
  text-align: center;
  max-width: 520px;
}

.error-code {
  font-size: 72px;
  font-weight: 800;
  color: var(--color-accent);
  line-height: 1;
  margin-bottom: 16px;
}

.error-title {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 12px;
}

.error-desc {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 32px;
}

.error-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  justify-content: center;
}

.error-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-small);
  min-height: 44px;
  transition: background-color var(--transition-base), color var(--transition-base), border-color var(--transition-base);
}

.error-link:first-child {
  background-color: var(--color-accent);
  color: #ffffff;
  border: 1px solid var(--color-accent);
}

.error-link:first-child:hover {
  background-color: #dc2626;
  border-color: #dc2626;
  color: #ffffff;
}

.error-link:last-child {
  background-color: var(--color-bg-card);
  color: var(--color-primary);
  border: 1px solid var(--color-border);
}

.error-link:last-child:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ============================================================
   RESPONSIVE — 响应式断点
   ============================================================ */
/* 平板：1024px 及以下 */
@media (max-width: 1024px) {
  .capability-grid,
  .delivery-grid,
  .related-grid,
  .guide-grid {
    grid-template-columns: repeat(2, 1fr);
  }

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

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

  .page-layout {
    grid-template-columns: 1fr 280px;
    gap: 32px;
  }

  .footer-inner {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }
}

/* 手机：768px 及以下 */
@media (max-width: 768px) {
  /* 页头 */
  .header-inner {
    padding: 0 16px;
    height: 64px;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background-color: var(--color-bg-card);
    border-bottom: 1px solid var(--color-border);
    box-shadow: 0 8px 16px rgba(17, 24, 39, 0.08);
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px 16px 16px;
  }

  .nav-list.is-open {
    display: flex;
  }

  .nav-item {
    width: 100%;
  }

  .nav-link {
    padding: 14px 12px;
    border-radius: var(--radius-small);
    font-size: 16px;
  }

  /* 内页主容器 */
  .inner-main {
    padding: 0 16px 48px;
  }

  /* 面包屑与标题 */
  .breadcrumb {
    padding: 16px 0 8px;
  }

  .page-header {
    padding: 20px 0 32px;
    margin-bottom: 36px;
  }

  .page-title {
    font-size: 24px;
  }

  .page-description {
    font-size: 15px;
  }

  /* 首页 hero */
  .hero-section {
    padding: 64px 0;
  }

  .hero-title {
    font-size: 28px;
  }

  .hero-subtitle {
    font-size: 16px;
  }

  .hero-actions {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }

  .hero-actions .btn {
    width: 100%;
  }

  /* 首页模块间距 */
  .capability-section,
  .process-overview-section,
  .scenario-section,
  .help-guide-section {
    padding: 48px 16px 0;
  }

  .content-media {
    padding: 0 16px;
  }

  /* 首页网格 */
  .capability-grid,
  .scenario-grid,
  .delivery-grid,
  .related-grid,
  .guide-grid,
  .issue-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .help-category-grid,
  .category-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  /* 首页流程步骤 */
  .process-step {
    gap: 16px;
    padding: 16px 0;
  }

  .process-step .step-number {
    width: 36px;
    height: 36px;
    font-size: 15px;
  }

  /* 首页关联链接 */
  .home-main .related-links {
    padding: 32px 16px 48px;
    gap: 8px 16px;
  }

  /* 服务矩阵表格 */
  .service-table-wrap {
    overflow-x: auto;
  }

  .service-matrix-table {
    min-width: 640px;
  }

  /* 解决方案 */
  .section {
    margin-bottom: 48px;
  }

  .path-block {
    padding: 20px 16px;
  }

  .path-step {
    padding: 16px;
  }

  .back-to-top {
    flex-direction: column;
    align-items: flex-start;
  }

  /* 合作流程 */
  .timeline-item {
    gap: 16px;
  }

  .timeline-number {
    width: 40px;
    height: 40px;
    font-size: 15px;
  }

  .feedback-layout {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .feedback-media {
    order: 2;
  }

  .feedback-content {
    order: 1;
  }

  /* 关于我们 */
  .page-layout {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .layout-aside {
    order: 2;
  }

  /* 页脚 */
  .footer-inner {
    grid-template-columns: 1fr 1fr;
    gap: 28px;
    padding: 40px 16px 24px;
  }

  .footer-bottom {
    padding: 16px;
  }
}

/* 小手机：480px 及以下 */
@media (max-width: 480px) {
  .footer-inner {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .hero-title {
    font-size: 26px;
  }

  .hero-subtitle {
    font-size: 15px;
  }

  .section-title {
    font-size: 20px;
  }

  .error-code {
    font-size: 56px;
  }

  .error-title {
    font-size: 20px;
  }

  .error-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .error-link {
    width: 100%;
  }
}