/* ==========================================================================
   91吃瓜 · 整站样式表
   版本：1.0
   说明：本样式表覆盖全站所有页面（首页、内页、404），按 base / layout /
   components / pages / responsive 分组组织。所有选择器均对应真实 DOM。
   ========================================================================== */

/* ==========================================================================
   Base —— 变量、重置、全局基础
   ========================================================================== */

:root {
  --color-primary: #1F3A5F;
  --color-primary-light: #2A4A78;
  --color-secondary: #8B9DAF;
  --color-bg: #F7F5F2;
  --color-text: #2B2B2B;
  --color-border: #D8D2C8;
  --color-white: #FFFFFF;
  --color-off-white: #F9F8F6;
  --font-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", SimSun, serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --container-width: 1140px;
  --container-narrow: 860px;
  --header-height: 72px;
  --radius-sm: 4px;
  --radius-md: 8px;
  --transition-base: 0.2s ease;
}

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

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.8;
  color: var(--color-text);
  background-color: var(--color-bg);
  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-primary-light);
}

ul,
ol {
  list-style-position: inside;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-serif);
  color: var(--color-primary);
  line-height: 1.4;
  font-weight: 700;
}

h1 {
  font-size: 36px;
}

h2 {
  font-size: 28px;
}

h3 {
  font-size: 20px;
}

p {
  margin-bottom: 1em;
}

/* 跳至正文链接（视觉隐藏，聚焦时显示） */
.skip-link {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 9999;
  padding: 12px 20px;
  background: var(--color-primary);
  color: var(--color-white);
  font-size: 14px;
  font-weight: 600;
  border-radius: 0 0 var(--radius-sm) 0;
  transform: translateY(-120%);
  transition: transform var(--transition-base);
  white-space: nowrap;
}

.skip-link:focus {
  transform: translateY(0);
  outline: 2px solid var(--color-secondary);
  outline-offset: 2px;
}

/* ==========================================================================
   Layout —— 页头、页脚、主容器、侧栏布局
   ========================================================================== */

/* 页头 */
.site-header {
  background: var(--color-white);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
}

.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 {
  display: inline-flex;
  align-items: baseline;
  gap: 10px;
  flex-shrink: 0;
}

.brand-name {
  font-family: var(--font-serif);
  font-size: 24px;
  font-weight: 700;
  color: var(--color-primary);
  letter-spacing: 0.02em;
}

.brand-tagline {
  font-size: 12px;
  color: var(--color-secondary);
  letter-spacing: 0.05em;
  white-space: nowrap;
}

/* 主导航 */
.main-nav {
  display: flex;
  align-items: center;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 4px;
  list-style: none;
}

.nav-link {
  display: block;
  padding: 8px 14px;
  font-size: 15px;
  font-weight: 500;
  color: var(--color-text);
  border-radius: var(--radius-sm);
  transition: background var(--transition-base), color var(--transition-base);
}

.nav-link:hover {
  color: var(--color-primary);
  background: rgba(31, 58, 95, 0.06);
}

.nav-link.is-current {
  color: var(--color-primary);
  background: rgba(31, 58, 95, 0.1);
  font-weight: 600;
}

/* 汉堡按钮（默认隐藏） */
.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 10px;
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  transition: border-color var(--transition-base);
}

.nav-toggle:hover {
  border-color: var(--color-primary);
}

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

/* 主内容 */
.site-main {
  flex: 1 0 auto;
  width: 100%;
}

/* 页脚 */
.site-footer {
  background: var(--color-primary);
  color: rgba(255, 255, 255, 0.85);
  margin-top: auto;
}

.footer-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 48px 24px 32px;
  display: grid;
  grid-template-columns: 1.2fr 1fr 1fr;
  gap: 40px;
}

.footer-brand h3 {
  color: var(--color-white);
  font-size: 20px;
  margin-bottom: 12px;
}

.footer-brand p {
  font-size: 14px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: 0;
}

.footer-nav h3,
.footer-services h3 {
  color: var(--color-white);
  font-size: 16px;
  margin-bottom: 14px;
}

.footer-nav ul,
.footer-services ul {
  list-style: none;
}

.footer-nav li,
.footer-services li {
  margin-bottom: 8px;
}

.footer-nav a {
  color: rgba(255, 255, 255, 0.75);
  font-size: 14px;
  transition: color var(--transition-base);
}

.footer-nav a:hover {
  color: var(--color-white);
}

.footer-services li {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.75);
  padding-left: 14px;
  position: relative;
}

.footer-services li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.7em;
  width: 6px;
  height: 6px;
  background: var(--color-secondary);
  border-radius: 50%;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.15);
  text-align: center;
  padding: 16px 24px;
}

.footer-bottom p {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.6);
  margin-bottom: 0;
}

/* 面包屑 */
.breadcrumb {
  font-size: 14px;
  color: var(--color-secondary);
  padding: 16px 0 0;
}

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

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

.breadcrumb-sep {
  margin: 0 8px;
  color: var(--color-border);
}

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

.breadcrumb-wrap {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
}

.breadcrumb-list {
  display: flex;
  list-style: none;
  flex-wrap: wrap;
  gap: 4px;
}

.breadcrumb-list li {
  display: inline-flex;
  align-items: center;
}

.breadcrumb-list li + li::before {
  content: "/";
  margin: 0 8px;
  color: var(--color-border);
}

.breadcrumb-nav {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 20px 24px 0;
}

.breadcrumb-inner {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
}

/* 内页通用布局 */
.inner-main {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px 64px;
}

/* 侧栏布局：侧栏在前，主内容在后 */
.sidebar-left {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 40px;
  align-items: start;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px 64px;
}

/* 侧栏 */
.side-nav {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  position: sticky;
  top: calc(var(--header-height) + 24px);
}

.side-nav-inner {
  display: block;
}

.side-nav-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-border);
}

.side-nav-list {
  list-style: none;
}

.side-nav-list li {
  margin-bottom: 4px;
}

.side-nav-list a {
  display: block;
  padding: 8px 12px;
  font-size: 14px;
  color: var(--color-text);
  border-radius: var(--radius-sm);
  border-left: 3px solid transparent;
  transition: background var(--transition-base), color var(--transition-base), border-color var(--transition-base);
}

.side-nav-list a:hover {
  color: var(--color-primary);
  background: rgba(31, 58, 95, 0.05);
  border-left-color: var(--color-primary);
}

.side-nav-extra {
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid var(--color-border);
}

.side-nav-extra p {
  font-size: 13px;
  color: var(--color-secondary);
  margin-bottom: 10px;
}

.side-nav-link {
  font-size: 14px;
  font-weight: 600;
}

.side-cta {
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid var(--color-border);
}

.side-cta p {
  font-size: 13px;
  color: var(--color-secondary);
  margin-bottom: 10px;
}

.side-cta a {
  display: inline-block;
  font-size: 14px;
  font-weight: 600;
  padding: 8px 14px;
  background: var(--color-primary);
  color: var(--color-white);
  border-radius: var(--radius-sm);
  transition: background var(--transition-base);
}

.side-cta a:hover {
  background: var(--color-primary-light);
}

/* 页面标题区 */
.page-header {
  padding: 24px 0 8px;
}

.page-title {
  font-size: 32px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 8px;
}

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

.page-intro {
  font-size: 16px;
  color: var(--color-text);
  margin: 12px 0 32px;
  max-width: 720px;
}

.page-lead {
  font-size: 16px;
  color: var(--color-text);
  margin-bottom: 24px;
  max-width: 720px;
}

.page-title-block {
  margin-bottom: 16px;
}

/* 通用容器 */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* 页面布局容器 */
.page-layout {
  width: 100%;
}

.layout-shell {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 40px;
  align-items: start;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px 64px;
}

/* ==========================================================================
   Components —— 按钮、卡片、FAQ、流程条、模块公用
   ========================================================================== */

/* 按钮 */
.btn {
  display: inline-block;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 600;
  border: 2px solid transparent;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--transition-base), color var(--transition-base), border-color var(--transition-base);
  text-align: center;
}

.btn-primary {
  display: inline-block;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 600;
  background: var(--color-primary);
  color: var(--color-white);
  border: 2px solid var(--color-primary);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--transition-base), color var(--transition-base), border-color var(--transition-base);
  text-align: center;
}

.btn-primary:hover {
  background: var(--color-primary-light);
  border-color: var(--color-primary-light);
  color: var(--color-white);
}

.btn-outline {
  display: inline-block;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 600;
  background: transparent;
  color: var(--color-white);
  border: 2px solid rgba(255, 255, 255, 0.8);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--transition-base), color var(--transition-base), border-color var(--transition-base);
  text-align: center;
}

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.15);
  border-color: var(--color-white);
  color: var(--color-white);
}

.btn-secondary {
  display: inline-block;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 600;
  background: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--transition-base), color var(--transition-base);
  text-align: center;
}

.btn-secondary:hover {
  background: rgba(31, 58, 95, 0.06);
  color: var(--color-primary);
}

/* 文本链接 */
.text-link {
  display: inline-block;
  font-size: 15px;
  font-weight: 600;
  color: var(--color-primary);
  border-bottom: 1px solid var(--color-primary);
  padding-bottom: 2px;
  transition: border-color var(--transition-base), color var(--transition-base);
}

.text-link:hover {
  color: var(--color-primary-light);
  border-bottom-color: var(--color-primary-light);
}

/* 区块标题 */
.section-head {
  text-align: center;
  margin-bottom: 40px;
}

.section-head h2 {
  font-size: 28px;
  margin-bottom: 12px;
}

.section-head p {
  font-size: 16px;
  color: var(--color-secondary);
  max-width: 680px;
  margin: 0 auto;
}

.section-link {
  text-align: center;
  margin-top: 32px;
}

/* 服务卡片（首页预览 + 服务页） */
.service-grid {
  display: grid;
  gap: 24px;
}

/* 首页服务预览：不对称四卡 */
.services-preview .service-grid {
  grid-template-columns: 1.2fr 0.9fr 1fr 0.85fr;
}

.services-preview .service-card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.services-preview .service-card:hover {
  border-color: var(--color-primary);
  box-shadow: 0 4px 16px rgba(31, 58, 95, 0.08);
}

.services-preview .service-card h3 {
  font-size: 18px;
  margin-bottom: 12px;
}

.services-preview .service-card p {
  font-size: 14px;
  line-height: 1.7;
  color: var(--color-text);
  margin-bottom: 16px;
}

.services-preview .service-card a {
  font-size: 14px;
  font-weight: 600;
}

/* 服务页卡片 */
.service-matrix-block .service-grid {
  grid-template-columns: repeat(2, 1fr);
}

.service-matrix-block .service-card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 32px 28px;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.service-matrix-block .service-card:hover {
  border-color: var(--color-primary);
  box-shadow: 0 4px 16px rgba(31, 58, 95, 0.08);
}

.service-matrix-block .service-card h3 {
  font-size: 20px;
  margin-bottom: 12px;
}

.service-matrix-block .service-card p {
  font-size: 15px;
  line-height: 1.7;
  margin-bottom: 10px;
}

.service-matrix-block .service-card .service-goal {
  font-weight: 600;
  color: var(--color-primary);
}

.service-matrix-block .service-card .service-deliverable {
  font-size: 14px;
  color: var(--color-secondary);
  margin-bottom: 0;
}

/* FAQ 手风琴 */
.faq-item {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  margin-bottom: 12px;
  overflow: hidden;
  transition: border-color var(--transition-base);
}

.faq-item:hover {
  border-color: var(--color-primary);
}

.faq-item summary {
  padding: 16px 20px;
  font-size: 16px;
  font-weight: 600;
  color: var(--color-primary);
  cursor: pointer;
  list-style: none;
  position: relative;
  padding-right: 44px;
  transition: background var(--transition-base);
}

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

.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 18px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 22px;
  font-weight: 400;
  color: var(--color-secondary);
  transition: transform var(--transition-base);
}

.faq-item[open] summary::after {
  content: "−";
}

.faq-item[open] summary {
  background: rgba(31, 58, 95, 0.04);
}

.faq-item .faq-answer {
  padding: 0 20px 16px;
  border-top: 1px solid var(--color-border);
  padding-top: 12px;
}

.faq-item .faq-answer p {
  font-size: 15px;
  line-height: 1.8;
  margin-bottom: 8px;
}

.faq-item p {
  padding: 0 20px 16px;
  font-size: 15px;
  line-height: 1.8;
}

/* 相关链接 */
.related-links {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  padding: 24px 0;
  border-top: 1px solid var(--color-border);
  margin-top: 48px;
}

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

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

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

/* 内容图片 */
.content-figure {
  margin: 24px 0;
}

.content-figure img {
  width: 100%;
  border-radius: var(--radius-md);
  object-fit: cover;
}

.content-figure figcaption,
.execution-figure figcaption,
.content-media figcaption,
.page-hero-image figcaption {
  font-size: 13px;
  color: var(--color-secondary);
  text-align: center;
  padding: 10px 0 0;
}

/* 合作 CTA 区块 */
.cooperation-cta {
  text-align: center;
}

/* ==========================================================================
   Pages —— 首页
   ========================================================================== */

/* Hero 首屏 */
.hero {
  position: relative;
  min-height: 520px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  background: var(--color-primary);
}

.hero-media {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.45;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 720px;
  padding: 60px 24px;
  text-align: center;
  color: var(--color-white);
}

.hero-content h1 {
  font-size: 40px;
  color: var(--color-white);
  margin-bottom: 16px;
  line-height: 1.3;
}

.hero-lead {
  font-size: 18px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: 32px;
}

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

/* 快速入口 */
.quick-links {
  padding: 56px 0 0;
}

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

.quick-card {
  display: block;
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.quick-card:hover {
  border-color: var(--color-primary);
  box-shadow: 0 4px 16px rgba(31, 58, 95, 0.08);
}

.quick-card h2 {
  font-size: 18px;
  margin-bottom: 10px;
}

.quick-card p {
  font-size: 14px;
  color: var(--color-secondary);
  margin-bottom: 0;
  line-height: 1.7;
}

/* 企业定位 */
.positioning {
  padding: 56px 0;
}

.positioning-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.positioning-text p {
  font-size: 16px;
  line-height: 1.8;
  margin-bottom: 16px;
}

.positioning-text .text-link {
  margin-top: 8px;
}

.positioning-image figure {
  margin: 0;
}

.positioning-image img {
  width: 100%;
  border-radius: var(--radius-md);
  object-fit: cover;
}

/* 服务矩阵预览 */
.services-preview {
  padding: 56px 0;
  border-top: 1px solid var(--color-border);
}

/* 案例预览 */
.cases-preview {
  padding: 56px 0;
  border-top: 1px solid var(--color-border);
}

.case-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
  margin-bottom: 32px;
}

.case-row.reverse {
  direction: rtl;
}

.case-row.reverse > * {
  direction: ltr;
}

.case-text h3 {
  font-size: 22px;
  margin-bottom: 12px;
}

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

.case-note {
  background: var(--color-white);
  border-left: 4px solid var(--color-primary);
  border-radius: var(--radius-sm);
  padding: 24px;
}

.case-note span {
  display: block;
  font-size: 13px;
  font-weight: 600;
  color: var(--color-secondary);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 8px;
}

.case-note p {
  font-size: 15px;
  line-height: 1.8;
  margin-bottom: 0;
  color: var(--color-text);
}

/* 流程预览 */
.process-preview {
  padding: 56px 0;
  border-top: 1px solid var(--color-border);
}

.process-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-top: 32px;
}

.step-item {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  position: relative;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.step-item:hover {
  border-color: var(--color-primary);
  box-shadow: 0 4px 16px rgba(31, 58, 95, 0.08);
}

.step-num {
  display: inline-block;
  font-family: var(--font-serif);
  font-size: 28px;
  font-weight: 700;
  color: var(--color-secondary);
  margin-bottom: 12px;
}

.step-item h3 {
  font-size: 17px;
  margin-bottom: 10px;
}

.step-item p {
  font-size: 14px;
  color: var(--color-text);
  line-height: 1.7;
  margin-bottom: 0;
}

/* 标准预览 */
.standard-preview {
  padding: 56px 0;
  border-top: 1px solid var(--color-border);
}

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

.standard-item {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.standard-item:hover {
  border-color: var(--color-primary);
  box-shadow: 0 4px 16px rgba(31, 58, 95, 0.08);
}

.standard-index {
  display: block;
  font-family: var(--font-serif);
  font-size: 16px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 10px;
}

.standard-item h3 {
  font-size: 17px;
  margin-bottom: 10px;
}

.standard-item p {
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 0;
}

/* FAQ 预览 */
.faq-preview {
  padding: 56px 0;
  border-top: 1px solid var(--color-border);
}

.faq-list-compact {
  max-width: 760px;
  margin: 0 auto;
}

/* 合作 CTA */
.cooperation-cta {
  padding: 56px 0;
}

.cta-box {
  background: var(--color-primary);
  border-radius: var(--radius-md);
  padding: 56px 48px;
  text-align: center;
}

.cta-box h2 {
  color: var(--color-white);
  font-size: 26px;
  margin-bottom: 12px;
}

.cta-box p {
  color: rgba(255, 255, 255, 0.85);
  font-size: 16px;
  max-width: 560px;
  margin: 0 auto 28px;
}

/* ==========================================================================
   Pages —— 服务内容（service.html）
   ========================================================================== */

.service-matrix-block,
.app-scenes-block,
.service-mode-block,
.cooperation-entry-block {
  padding: 32px 0;
  border-bottom: 1px solid var(--color-border);
}

.service-matrix-block:first-of-type,
.app-scenes-block:first-of-type,
.service-mode-block:first-of-type,
.cooperation-entry-block:first-of-type {
  padding-top: 16px;
}

.service-matrix-block h2,
.app-scenes-block h2,
.service-mode-block h2,
.cooperation-entry-block h2 {
  font-size: 24px;
  margin-bottom: 12px;
}

.service-matrix-block > p,
.app-scenes-block > p,
.service-mode-block > p,
.cooperation-entry-block > p {
  font-size: 15px;
  color: var(--color-secondary);
  margin-bottom: 24px;
  max-width: 720px;
}

.app-scenes-block .scene-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 24px;
}

.scene-text {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 24px;
}

.scene-text h3 {
  font-size: 18px;
  margin-bottom: 10px;
}

.scene-text p {
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 0;
}

.service-mode-block .mode-list {
  list-style: none;
}

.service-mode-block .mode-list li {
  padding: 12px 0;
  border-bottom: 1px solid var(--color-border);
  font-size: 15px;
  line-height: 1.7;
}

.service-mode-block .mode-list li:last-child {
  border-bottom: none;
}

.service-mode-block .mode-list strong {
  color: var(--color-primary);
  margin-right: 8px;
}

.cooperation-entry-block .entry-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  margin-top: 20px;
}

/* ==========================================================================
   Pages —— 典型案例（cases.html）
   ========================================================================== */

.scenes-list {
  padding: 24px 0 8px;
}

.scenes-list > h2 {
  font-size: 24px;
  margin-bottom: 20px;
}

.scene-cards {
  display: grid;
  gap: 32px;
}

.scene-card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 28px;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.scene-card:hover {
  border-color: var(--color-primary);
  box-shadow: 0 4px 16px rgba(31, 58, 95, 0.08);
}

.scene-card img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-radius: var(--radius-sm);
  margin-bottom: 20px;
}

.scene-card h3 {
  font-size: 20px;
  margin-bottom: 12px;
}

.scene-card p {
  font-size: 15px;
  line-height: 1.7;
  margin-bottom: 10px;
}

.scene-card p strong {
  color: var(--color-primary);
  font-weight: 600;
}

.scene-card .scene-goal {
  font-weight: 600;
  color: var(--color-primary);
}

.scene-card a {
  display: inline-block;
  font-size: 14px;
  font-weight: 600;
  margin-top: 8px;
}

.scene-guide {
  padding: 32px 0;
  border-top: 1px solid var(--color-border);
}

.scene-guide > h2 {
  font-size: 24px;
  margin-bottom: 20px;
}

.guide-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.guide-item {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 24px;
}

.guide-item h3 {
  font-size: 17px;
  margin-bottom: 10px;
}

.guide-item p {
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 0;
}

.guide-note {
  font-size: 14px;
  color: var(--color-secondary);
  margin-top: 20px;
  padding: 16px 20px;
  background: var(--color-white);
  border-left: 4px solid var(--color-primary);
  border-radius: var(--radius-sm);
}

.consult-entry {
  padding: 32px 0;
  text-align: center;
}

.consult-entry h2 {
  font-size: 24px;
  margin-bottom: 12px;
}

.consult-entry p {
  font-size: 15px;
  color: var(--color-secondary);
  max-width: 560px;
  margin: 0 auto 24px;
}

/* ==========================================================================
   Pages —— 合作流程（process.html）
   ========================================================================== */

.page-content {
  min-width: 0;
}

.page-hero-image {
  margin: 24px 0 32px;
}

.page-hero-image img {
  width: 100%;
  max-height: 320px;
  object-fit: cover;
  border-radius: var(--radius-md);
}

.process-stage {
  padding: 32px 0;
  border-bottom: 1px solid var(--color-border);
  display: block;
}

.process-stage:last-of-type {
  border-bottom: none;
}

.stage-number {
  display: inline-block;
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 700;
  color: var(--color-white);
  background: var(--color-primary);
  width: 44px;
  height: 44px;
  line-height: 44px;
  text-align: center;
  border-radius: 50%;
  margin-bottom: 16px;
}

.process-stage h2 {
  font-size: 24px;
  margin-bottom: 16px;
}

.stage-body {
  display: block;
  max-width: 100%;
}

.stage-body p {
  font-size: 15px;
  line-height: 1.8;
  margin-bottom: 14px;
  max-width: 100%;
}

.stage-body h3 {
  font-size: 17px;
  margin: 20px 0 10px;
}

.stage-list {
  list-style: disc;
  padding-left: 20px;
  margin-bottom: 14px;
}

.stage-list li {
  font-size: 15px;
  line-height: 1.8;
  margin-bottom: 6px;
}

.preparation-section {
  padding: 32px 0;
  border-top: 1px solid var(--color-border);
}

.preparation-section h2 {
  font-size: 24px;
  margin-bottom: 12px;
}

.preparation-section .section-intro {
  font-size: 15px;
  color: var(--color-secondary);
  margin-bottom: 20px;
}

.preparation-list {
  list-style: none;
  counter-reset: prep-counter;
}

.preparation-list li {
  counter-increment: prep-counter;
  padding: 12px 0;
  border-bottom: 1px solid var(--color-border);
  font-size: 15px;
  line-height: 1.7;
  padding-left: 44px;
  position: relative;
}

.preparation-list li::before {
  content: counter(prep-counter);
  position: absolute;
  left: 0;
  top: 12px;
  width: 28px;
  height: 28px;
  background: var(--color-primary);
  color: var(--color-white);
  border-radius: 50%;
  font-size: 13px;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
}

.preparation-list li:last-child {
  border-bottom: none;
}

.cooperation-cta {
  padding: 40px 0;
  text-align: center;
}

.cooperation-cta h2 {
  font-size: 24px;
  margin-bottom: 12px;
}

.cooperation-cta p {
  font-size: 15px;
  color: var(--color-secondary);
  max-width: 560px;
  margin: 0 auto 24px;
}

/* ==========================================================================
   Pages —— 服务标准（standard.html）
   ========================================================================== */

.standard-intro {
  padding: 8px 0 24px;
}

.standard-intro p {
  font-size: 16px;
  line-height: 1.8;
  max-width: 720px;
}

.standard-list {
  padding: 24px 0;
  border-bottom: 1px solid var(--color-border);
}

.standard-list h2 {
  font-size: 22px;
  margin-bottom: 16px;
}

.standard-items {
  list-style: none;
}

.standard-items .standard-item {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  margin-bottom: 12px;
  transition: border-color var(--transition-base);
}

.standard-items .standard-item:hover {
  border-color: var(--color-primary);
}

.standard-items .standard-item h3 {
  font-size: 17px;
  margin-bottom: 8px;
}

.standard-items .standard-item p {
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 0;
}

.standard-execution {
  padding: 32px 0;
  border-bottom: 1px solid var(--color-border);
}

.standard-execution h2 {
  font-size: 24px;
  margin-bottom: 20px;
}

.execution-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  align-items: start;
}

.execution-text p {
  font-size: 15px;
  line-height: 1.8;
  margin-bottom: 14px;
}

.execution-figure img {
  width: 100%;
  border-radius: var(--radius-md);
  object-fit: cover;
}

.feedback-channel {
  padding: 32px 0;
}

.feedback-channel h2 {
  font-size: 24px;
  margin-bottom: 12px;
}

.feedback-channel p {
  font-size: 15px;
  color: var(--color-secondary);
  max-width: 640px;
  margin-bottom: 20px;
}

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

/* ==========================================================================
   Pages —— 常见问题（faq.html）
   ========================================================================== */

.page-title-area {
  margin-bottom: 8px;
}

.faq-group {
  padding: 24px 0;
  border-bottom: 1px solid var(--color-border);
}

.faq-group .group-title {
  font-size: 22px;
  margin-bottom: 16px;
}

.content-media-inline {
  margin: 0 0 20px;
}

.content-media img {
  width: 100%;
  max-height: 200px;
  object-fit: cover;
  border-radius: var(--radius-md);
}

.faq-more {
  padding: 32px 0;
  text-align: center;
}

.faq-more h2 {
  font-size: 24px;
  margin-bottom: 12px;
}

.faq-more p {
  font-size: 15px;
  color: var(--color-secondary);
  max-width: 560px;
  margin: 0 auto 24px;
}

/* ==========================================================================
   Pages —— 合作咨询（cooperation.html）
   ========================================================================== */

.cooperation-layout {
  max-width: 820px;
  margin: 0 auto;
  padding: 8px 0 0;
}

.cooperation-intro p {
  font-size: 16px;
  line-height: 1.8;
  margin-bottom: 20px;
}

.cooperation-hero-figure {
  margin: 0 0 32px;
}

.cooperation-hero-figure img {
  width: 100%;
  max-height: 320px;
  object-fit: cover;
  border-radius: var(--radius-md);
}

.cooperation-start-section {
  padding: 24px 0;
  border-top: 1px solid var(--color-border);
}

.cooperation-start-section h2,
.requirements-section h2,
.communication-notes-section h2,
.faq-guide-section h2,
.next-step-section h2 {
  font-size: 24px;
  margin-bottom: 12px;
}

.cooperation-start-section > p,
.requirements-section > p,
.communication-notes-section > p,
.faq-guide-section > p {
  font-size: 15px;
  color: var(--color-secondary);
  margin-bottom: 20px;
}

.start-steps-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.start-step-card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 24px;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.start-step-card:hover {
  border-color: var(--color-primary);
  box-shadow: 0 4px 16px rgba(31, 58, 95, 0.08);
}

.start-step-card h3 {
  font-size: 17px;
  margin-bottom: 10px;
}

.start-step-card p {
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 0;
}

.requirements-section {
  padding: 24px 0;
  border-top: 1px solid var(--color-border);
}

.requirements-list {
  list-style: none;
}

.requirements-list li {
  padding: 10px 0;
  border-bottom: 1px solid var(--color-border);
  font-size: 15px;
  line-height: 1.7;
  padding-left: 24px;
  position: relative;
}

.requirements-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.75em;
  width: 8px;
  height: 8px;
  background: var(--color-primary);
  border-radius: 2px;
}

.requirements-list li:last-child {
  border-bottom: none;
}

.communication-notes-section {
  padding: 24px 0;
  border-top: 1px solid var(--color-border);
}

.notes-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.note-card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 24px;
  transition: border-color var(--transition-base);
}

.note-card:hover {
  border-color: var(--color-primary);
}

.note-card h3 {
  font-size: 16px;
  margin-bottom: 10px;
}

.note-card p {
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 0;
}

.faq-guide-section {
  padding: 24px 0;
  border-top: 1px solid var(--color-border);
}

.faq-guide-section p {
  font-size: 15px;
  line-height: 1.8;
  margin-bottom: 12px;
}

.faq-guide-section a {
  font-weight: 600;
}

.next-step-section {
  padding: 32px 0;
  text-align: center;
}

.next-step-section h2 {
  font-size: 24px;
  margin-bottom: 12px;
}

.next-step-section p {
  font-size: 15px;
  color: var(--color-secondary);
  max-width: 600px;
  margin: 0 auto 12px;
}

/* ==========================================================================
   Pages —— 404
   ========================================================================== */

.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 60vh;
  padding: 48px 24px;
}

.error-content {
  text-align: center;
  max-width: 560px;
}

.error-code {
  font-family: var(--font-serif);
  font-size: 72px;
  font-weight: 700;
  color: var(--color-primary);
  line-height: 1;
  margin-bottom: 16px;
}

.error-content h1 {
  font-size: 28px;
  margin-bottom: 12px;
}

.error-desc {
  font-size: 16px;
  color: var(--color-text);
  margin-bottom: 24px;
}

.error-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 24px;
}

.error-btn {
  display: inline-block;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 600;
  background: var(--color-primary);
  color: var(--color-white);
  border-radius: var(--radius-sm);
  transition: background var(--transition-base);
}

.error-btn:hover {
  background: var(--color-primary-light);
  color: var(--color-white);
}

.error-link {
  display: inline-block;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 600;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
  border-radius: var(--radius-sm);
  transition: background var(--transition-base);
}

.error-link:hover {
  background: rgba(31, 58, 95, 0.06);
}

.error-help {
  font-size: 14px;
  color: var(--color-secondary);
  margin-bottom: 0;
}

/* ==========================================================================
   Responsive —— 响应式断点
   ========================================================================== */

/* 桌面端 1024px 及以上 */
@media (min-width: 1024px) {
  .nav-toggle {
    display: none;
  }

  .nav-list {
    display: flex;
  }
}

/* 平板与桌面小屏 768-1023px */
@media (max-width: 1023px) {
  .header-inner {
    padding: 0 20px;
  }

  .nav-toggle {
    display: flex;
  }

  .nav-list {
    display: none;
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: var(--color-white);
    border-bottom: 1px solid var(--color-border);
    box-shadow: 0 8px 24px rgba(31, 58, 95, 0.1);
    flex-direction: column;
    align-items: stretch;
    padding: 12px 20px;
    gap: 0;
  }

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

  .nav-list li {
    width: 100%;
  }

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

  .nav-link:hover {
    background: rgba(31, 58, 95, 0.06);
  }

  .sidebar-left,
  .layout-shell {
    grid-template-columns: 200px 1fr;
    gap: 24px;
    padding: 0 20px 48px;
  }

  .inner-main {
    padding: 0 20px 48px;
  }

  .footer-inner {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
    padding: 40px 20px 28px;
  }

  .services-preview .service-grid {
    grid-template-columns: 1fr 1fr;
  }

  .process-steps {
    grid-template-columns: 1fr 1fr;
  }

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

/* 手机端 767px 及以下 */
@media (max-width: 767px) {
  html {
    font-size: 15px;
  }

  h1 {
    font-size: 28px;
  }

  h2 {
    font-size: 22px;
  }

  h3 {
    font-size: 18px;
  }

  .header-inner {
    height: 60px;
    padding: 0 16px;
    gap: 12px;
  }

  .brand-name {
    font-size: 20px;
  }

  .brand-tagline {
    display: none;
  }

  .nav-toggle {
    display: flex;
    width: 40px;
    height: 40px;
  }

  .nav-list {
    top: 60px;
    padding: 8px 16px;
  }

  .container,
  .inner-main,
  .breadcrumb-wrap,
  .breadcrumb-nav {
    padding-left: 16px;
    padding-right: 16px;
  }

  .sidebar-left,
  .layout-shell {
    display: block;
    padding: 0 16px 40px;
  }

  .side-nav {
    display: none;
    position: static;
    margin-bottom: 24px;
  }

  /* 手机端侧栏隐藏，主内容优先 */
  .sidebar-left .side-nav,
  .layout-shell .side-nav {
    display: none;
  }

  /* 面包屑 */
  .breadcrumb {
    padding: 12px 0 0;
    font-size: 13px;
  }

  .page-header {
    padding: 16px 0 8px;
  }

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

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

  /* 首页 Hero */
  .hero {
    min-height: 400px;
  }

  .hero-content {
    padding: 40px 20px;
  }

  .hero-content h1 {
    font-size: 30px;
  }

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

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

  .hero-actions .btn,
  .hero-actions .btn-primary,
  .hero-actions .btn-outline {
    width: 100%;
    max-width: 280px;
    margin: 0 auto;
  }

  /* 快速入口 */
  .quick-links {
    padding: 40px 0 0;
  }

  .quick-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  /* 定位 */
  .positioning {
    padding: 40px 0;
  }

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

  /* 服务预览 */
  .services-preview {
    padding: 40px 0;
  }

  .services-preview .service-grid {
    grid-template-columns: 1fr;
  }

  .service-matrix-block .service-grid {
    grid-template-columns: 1fr;
  }

  /* 案例预览 */
  .cases-preview {
    padding: 40px 0;
  }

  .case-row {
    grid-template-columns: 1fr;
    gap: 20px;
    margin-bottom: 24px;
  }

  .case-row.reverse {
    direction: ltr;
  }

  /* 流程预览 */
  .process-preview {
    padding: 40px 0;
  }

  .process-steps {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  /* 标准预览 */
  .standard-preview {
    padding: 40px 0;
  }

  .standard-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  /* FAQ 预览 */
  .faq-preview {
    padding: 40px 0;
  }

  /* 合作 CTA */
  .cooperation-cta {
    padding: 40px 0;
  }

  .cta-box {
    padding: 40px 24px;
  }

  .cta-box h2 {
    font-size: 22px;
  }

  /* 服务页 */
  .app-scenes-block .scene-row {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .entry-actions {
    flex-direction: column;
  }

  .entry-actions .btn-primary,
  .entry-actions .btn-secondary {
    width: 100%;
  }

  /* 案例页 */
  .scene-card {
    padding: 20px;
  }

  .scene-card img {
    height: 160px;
  }

  .guide-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  /* 流程页 */
  .page-hero-image img {
    max-height: 200px;
  }

  .stage-body h3 {
    font-size: 16px;
  }

  /* 标准页 */
  .execution-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .channel-actions {
    flex-direction: column;
  }

  .channel-actions .btn-primary,
  .channel-actions .btn-secondary {
    width: 100%;
  }

  /* FAQ 页 */
  .faq-item summary {
    font-size: 15px;
    padding: 14px 40px 14px 16px;
  }

  .faq-item .faq-answer {
    padding: 0 16px 14px;
  }

  /* 合作页 */
  .cooperation-layout {
    padding: 0 16px;
  }

  .start-steps-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .notes-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .cooperation-hero-figure img {
    max-height: 200px;
  }

  /* 页脚 */
  .footer-inner {
    grid-template-columns: 1fr;
    gap: 24px;
    padding: 32px 16px 24px;
  }

  .footer-bottom {
    padding: 14px 16px;
  }

  /* 相关链接 */
  .related-links {
    gap: 10px;
    padding: 20px 0;
  }

  .related-links-item {
    padding: 6px 10px;
    font-size: 13px;
  }

  /* 404 */
  .error-code {
    font-size: 56px;
  }

  .error-actions {
    flex-direction: column;
    gap: 12px;
  }

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

/* 超小屏 400px 及以下 */
@media (max-width: 400px) {
  .brand-name {
    font-size: 18px;
  }

  .hero-content h1 {
    font-size: 26px;
  }

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

  .section-head h2 {
    font-size: 22px;
  }

  .cta-box {
    padding: 32px 16px;
  }
}

/* ==========================================================================
   动效增强（不阻塞初始可见性）
   ========================================================================== */

@media (prefers-reduced-motion: no-preference) {
  .quick-card,
  .service-card,
  .step-item,
  .standard-item,
  .scene-card,
  .start-step-card,
  .note-card {
    transition: border-color var(--transition-base), box-shadow var(--transition-base), transform 0.3s ease;
  }

  .quick-card:hover,
  .service-card:hover,
  .step-item:hover,
  .standard-item:hover,
  .scene-card:hover,
  .start-step-card:hover,
  .note-card:hover {
    transform: translateY(-2px);
  }
}

/* 滚动锚点偏移补偿（fix 固定页头遮挡） */
section[id],
div[id] {
  scroll-margin-top: calc(var(--header-height) + 16px);
}

/* 程序验收反馈：移动端防溢出 */
@media (max-width: 768px) {
  .site-main,
  .site-main * {
    min-width: 0;
    max-width: 100%;
  }

  .site-main :is(h1, h2, h3, h4, p, a, span) {
    overflow-wrap: anywhere;
  }
}