/* ==========================================================================
   base
   ========================================================================== */

:root {
  --color-text: #1a1a1a;
  --color-text-secondary: #6b6b6b;
  --color-bg: #f7f6f4;
  --color-accent: #3e6b5d;
  --color-accent-dark: #2f5247;
  --color-border: #e4e2de;
  --color-card: #ffffff;
  --font-serif: "Songti SC", "SimSun", "Noto Serif SC", "STSong", serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --container-width: 1140px;
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --space-section: 48px;
  --space-block: 32px;
}

*,
*::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: 1.75;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

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

h1,
h2,
h3,
h4 {
  font-family: var(--font-serif);
  line-height: 1.4;
  color: var(--color-text);
}

h1 {
  font-size: 30px;
  font-weight: 700;
}

h2 {
  font-size: 22px;
  font-weight: 700;
}

h3 {
  font-size: 17px;
  font-weight: 600;
}

p {
  margin-bottom: 12px;
}

p:last-child {
  margin-bottom: 0;
}

/* ==========================================================================
   layout
   ========================================================================== */

.site-header {
  background-color: var(--color-card);
  border-bottom: 1px solid var(--color-border);
}

.header-shell {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.site-main {
  min-height: 60vh;
}

.inner-main {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 32px 24px 64px;
}

.site-footer {
  background-color: #2c2c2c;
  color: #d5d3cf;
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding: 20px 24px;
  text-align: center;
}

.footer-bottom p {
  max-width: var(--container-width);
  margin: 0 auto;
  font-size: 13px;
  color: #a8a6a1;
}

/* 面包屑 */

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 24px;
}

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

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

.breadcrumb-sep {
  color: #b8b5b0;
}

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

/* 页面标题区 */

.page-header {
  margin-bottom: 40px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--color-border);
}

.page-title {
  font-size: 30px;
  margin-bottom: 12px;
}

.page-description {
  font-size: 16px;
  color: var(--color-text-secondary);
  max-width: 720px;
  line-height: 1.8;
}

/* 区块标题 */

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

.section-desc,
.section-intro,
.section-lead {
  font-size: 15px;
  color: var(--color-text-secondary);
  margin-bottom: 28px;
  max-width: 760px;
}

/* ==========================================================================
   components
   ========================================================================== */

/* 品牌 */

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

.brand-name {
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: 0.02em;
}

.brand-tagline {
  font-size: 12px;
  color: var(--color-text-secondary);
  display: none;
}

/* 导航 */

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

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

.nav-list li a {
  display: block;
  padding: 8px 14px;
  font-size: 14px;
  color: var(--color-text);
  border-radius: var(--radius-sm);
  transition: background-color 0.2s ease, color 0.2s ease;
}

.nav-list li a:hover {
  background-color: rgba(62, 107, 93, 0.08);
  color: var(--color-accent);
}

.nav-list li a.is-current {
  color: var(--color-accent);
  font-weight: 600;
  background-color: rgba(62, 107, 93, 0.1);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  align-items: center;
  gap: 6px;
}

.nav-toggle-icon {
  display: block;
  width: 20px;
  height: 2px;
  background-color: var(--color-text);
  position: relative;
}

.nav-toggle-icon::before,
.nav-toggle-icon::after {
  content: "";
  position: absolute;
  left: 0;
  width: 20px;
  height: 2px;
  background-color: var(--color-text);
}

.nav-toggle-icon::before {
  top: -6px;
}

.nav-toggle-icon::after {
  top: 6px;
}

.nav-toggle-text {
  font-size: 13px;
  color: var(--color-text);
}

/* 全局索引按钮 */

.global-index-btn {
  background: none;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 8px 16px;
  font-size: 14px;
  color: var(--color-text);
  cursor: pointer;
  margin-left: 12px;
  flex-shrink: 0;
  transition: border-color 0.2s ease, color 0.2s ease;
}

.global-index-btn:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* 按钮 */

.btn-primary,
.btn-ghost,
.btn-light {
  display: inline-block;
  padding: 10px 24px;
  font-size: 15px;
  font-weight: 500;
  border-radius: var(--radius-sm);
  transition: background-color 0.2s ease, color 0.2s ease,
    border-color 0.2s ease;
}

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

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

.btn-ghost {
  background-color: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

.btn-ghost:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

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

.btn-light:hover {
  background-color: transparent;
  color: #ffffff;
}

/* 文字链接 */

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 14px;
  font-weight: 500;
}

.text-link::after {
  content: "→";
  font-size: 14px;
}

/* 卡片通用 */

.window-card,
.solution-card,
.category-card,
.principle-card,
.suitable-card,
.related-card {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
}

/* 图片容器 */

.content-media {
  margin: 24px 0;
}

.content-media img,
.content-media figcaption {
  display: block;
}

.content-media figcaption {
  font-size: 13px;
  color: var(--color-text-secondary);
  margin-top: 10px;
  padding-left: 4px;
}

.content-media-primary {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  margin: 0;
  z-index: 0;
}

.content-media-primary img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.content-media-primary figcaption {
  position: absolute;
  bottom: 12px;
  left: 12px;
  background-color: rgba(0, 0, 0, 0.55);
  color: #e8e6e2;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  font-size: 12px;
}

.content-media-inline {
  margin: 0 0 28px;
}

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

/* 表格 */

.spec-table-wrap,
.table-wrapper {
  overflow-x: auto;
  margin: 24px 0;
}

.spec-table,
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  background-color: var(--color-card);
}

.spec-table th,
.spec-table td,
.comparison-table th,
.comparison-table td {
  padding: 14px 16px;
  text-align: left;
  border-bottom: 1px solid var(--color-border);
  vertical-align: top;
}

.spec-table th,
.comparison-table th {
  background-color: #f0efec;
  font-weight: 600;
  font-size: 14px;
  white-space: nowrap;
}

.spec-table tr:last-child td,
.comparison-table tr:last-child td {
  border-bottom: none;
}

/* 页脚 */

.footer-logo {
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 700;
  color: #ffffff;
  display: inline-block;
  margin-bottom: 12px;
}

.footer-desc {
  font-size: 14px;
  line-height: 1.7;
  color: #b5b3ae;
}

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

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

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

.footer-nav ul li a {
  font-size: 14px;
  color: #b5b3ae;
  transition: color 0.2s ease;
}

.footer-nav ul li a:hover {
  color: #ffffff;
}

.footer-boundary p {
  font-size: 13px;
  color: #a8a6a1;
  line-height: 1.7;
}

/* ==========================================================================
   pages
   ========================================================================== */

/* ---------- index.html ---------- */

.home-main {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px 64px;
}

/* 首屏服务窗口区 */

.hero-window-section {
  position: relative;
  padding: 56px 0 48px;
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 48px;
  align-items: start;
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero-content h1 {
  font-size: 30px;
  line-height: 1.45;
  margin-bottom: 16px;
}

.hero-lead {
  font-size: 16px;
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 28px;
}

.hero-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.hero-visual {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  overflow: hidden;
  border-radius: var(--radius-lg);
}

.hero-visual img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.service-windows {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.window-card {
  padding: 20px 24px;
}

.window-title {
  font-size: 17px;
  margin-bottom: 8px;
}

.window-desc {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 8px;
}

.window-reply {
  font-size: 13px;
  color: var(--color-accent);
  font-weight: 500;
}

/* 服务状态总览条 */

.service-status-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background-color: var(--color-border);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  margin-bottom: var(--space-section);
}

.status-item {
  background-color: var(--color-card);
  padding: 20px 24px;
}

.status-flag {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: var(--color-accent);
  margin-bottom: 6px;
}

.status-text {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin: 0;
}

/* 常见需求索引 */

.requirements-index {
  margin-bottom: var(--space-section);
}

.requirement-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1px;
  background-color: var(--color-border);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.requirement-row {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 20px 24px;
  background-color: var(--color-card);
  transition: background-color 0.2s ease;
}

.requirement-row:hover {
  background-color: #f0efec;
}

.req-type {
  font-family: var(--font-serif);
  font-size: 15px;
  font-weight: 600;
  color: var(--color-accent);
  flex-shrink: 0;
  min-width: 84px;
}

.req-desc {
  font-size: 14px;
  color: var(--color-text-secondary);
  flex: 1;
}

.req-link {
  font-size: 14px;
  font-weight: 500;
  flex-shrink: 0;
}

/* 解决方案对比区 */

.solutions-compare {
  margin-bottom: var(--space-section);
}

.compare-cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 32px;
}

.solution-card {
  padding: 24px;
}

.solution-name {
  font-size: 18px;
  margin-bottom: 12px;
}

.solution-conditions {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 16px;
}

.card-link {
  display: inline-block;
  font-size: 14px;
  font-weight: 500;
}

/* 操作路线 */

.operation-route {
  margin-bottom: var(--space-section);
}

.route-steps {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  counter-reset: route-step;
}

.route-step {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 24px;
  position: relative;
}

.step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background-color: var(--color-accent);
  color: #ffffff;
  font-family: var(--font-serif);
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 14px;
}

.route-step h3 {
  font-size: 16px;
  margin-bottom: 8px;
}

.route-step p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin: 0;
}

/* 支持摘要 */

.support-summary {
  margin-bottom: var(--space-section);
}

.support-boundary-item {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  margin-bottom: 16px;
}

.support-boundary-item h3 {
  font-size: 16px;
  margin-bottom: 6px;
}

.support-boundary-item p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin: 0;
}

/* 合作入口横幅 */

.cooperation-banner {
  background-color: var(--color-accent);
  border-radius: var(--radius-lg);
  padding: 40px 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  margin-bottom: var(--space-section);
}

.banner-text h2 {
  color: #ffffff;
  margin-bottom: 8px;
}

.banner-text p {
  color: rgba(255, 255, 255, 0.9);
  font-size: 15px;
  margin: 0;
}

/* 相关链接 */

.related-links {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  padding: 16px 0;
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 32px;
}

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

.related-links-item {
  font-size: 14px;
}

/* ---------- requirements.html ---------- */

.category-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-bottom: 40px;
}

.category-card {
  padding: 24px;
}

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

.category-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 12px;
}

.category-card a {
  font-size: 13px;
  font-weight: 500;
}

.requirement-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background-color: var(--color-border);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  margin-bottom: 40px;
}

.requirement-item {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 0;
  background-color: var(--color-card);
}

.requirement-item + .requirement-item {
  border-top: 1px solid var(--color-border);
}

.requirement-media {
  overflow: hidden;
}

.requirement-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.requirement-content {
  padding: 28px 32px;
}

.requirement-content h3 {
  font-size: 18px;
  margin-bottom: 12px;
}

.requirement-content p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 8px;
}

.requirement-content p strong {
  color: var(--color-text);
  font-weight: 600;
}

.requirement-content .text-link {
  margin-top: 12px;
}

.handoff-note {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 32px;
}

.handoff-content p {
  font-size: 14px;
  color: var(--color-text-secondary);
}

/* ---------- solutions.html ---------- */

.solutions-overview {
  margin-bottom: 40px;
}

.compare-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 40px;
}

.solution-card-media {
  margin: -24px -24px 20px;
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  overflow: hidden;
}

.solution-card-media img {
  width: 100%;
  height: 180px;
  object-fit: cover;
}

.solution-tag {
  font-size: 13px;
  font-weight: 600;
  color: var(--color-accent);
  margin: 16px 0 8px;
}

.solution-card ul {
  list-style: none;
  margin-bottom: 16px;
}

.solution-card ul li {
  font-size: 14px;
  color: var(--color-text-secondary);
  padding: 4px 0 4px 16px;
  position: relative;
}

.solution-card ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 14px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--color-accent);
}

.solutions-table-section {
  margin-bottom: 40px;
}

.guidance-list {
  list-style: none;
  counter-reset: guidance;
}

.guidance-list li {
  counter-increment: guidance;
  font-size: 15px;
  color: var(--color-text-secondary);
  padding: 10px 0 10px 36px;
  position: relative;
  border-bottom: 1px solid var(--color-border);
}

.guidance-list li::before {
  content: counter(guidance);
  position: absolute;
  left: 0;
  top: 10px;
  font-family: var(--font-serif);
  font-weight: 600;
  color: var(--color-accent);
}

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

.related-list li {
  margin-bottom: 8px;
}

/* ---------- guide.html ---------- */

.layout-shell {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 48px;
  align-items: start;
}

.sidebar-left {
  grid-template-columns: 260px 1fr;
}

.guide-toc {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 24px;
  position: sticky;
  top: 20px;
}

.guide-toc h2 {
  font-size: 16px;
  margin-bottom: 16px;
}

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

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

.toc-list li a {
  display: block;
  padding: 8px 12px;
  font-size: 14px;
  color: var(--color-text);
  border-radius: var(--radius-sm);
  border-left: 2px solid transparent;
  transition: background-color 0.2s ease, border-color 0.2s ease;
}

.toc-list li a:hover {
  background-color: rgba(62, 107, 93, 0.06);
  border-left-color: var(--color-accent);
  color: var(--color-accent);
}

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

.guide-section {
  margin-bottom: 48px;
}

.principle-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.principle-card {
  padding: 24px;
}

.principle-card h3 {
  font-size: 16px;
  margin-bottom: 8px;
}

.principle-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin: 0;
}

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

.step-item {
  display: flex;
  gap: 20px;
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 20px 24px;
}

.step-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background-color: var(--color-accent);
  color: #ffffff;
  font-family: var(--font-serif);
  font-size: 15px;
  font-weight: 600;
  flex-shrink: 0;
}

.step-body h3 {
  font-size: 16px;
  margin-bottom: 8px;
}

.step-body p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin: 0;
}

.guide-figure {
  margin: 32px 0;
}

.guide-figure img {
  width: 100%;
  height: auto;
  border-radius: var(--radius-md);
}

.guide-figure figcaption {
  font-size: 13px;
  color: var(--color-text-secondary);
  margin-top: 10px;
}

.misconception-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.misconception-item {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 20px 24px;
}

.misconception-item h3 {
  font-size: 15px;
  margin-bottom: 8px;
}

.misconception-item p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin: 0;
}

.related-link-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.related-link-list a {
  display: block;
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  font-size: 14px;
  font-weight: 500;
  transition: border-color 0.2s ease;
}

.related-link-list a:hover {
  border-color: var(--color-accent);
}

/* ---------- troubleshooting.html ---------- */

.trouble-category-index {
  margin-bottom: 48px;
}

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

.category-card-title {
  font-size: 16px;
  margin-bottom: 10px;
}

.category-card-desc {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 12px;
}

.category-card-link {
  font-size: 13px;
  font-weight: 500;
}

.troubleshooting-paths {
  margin-bottom: 48px;
}

.path-group {
  margin-bottom: 36px;
}

.path-group-title {
  font-size: 18px;
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-border);
}

.path-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

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

.path-item-title {
  font-size: 15px;
  margin-bottom: 12px;
}

.self-check-steps {
  list-style: decimal;
  padding-left: 20px;
  margin-bottom: 16px;
}

.self-check-steps li {
  font-size: 14px;
  color: var(--color-text-secondary);
  padding: 2px 0;
}

.path-entry {
  font-size: 14px;
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.faq-section {
  margin-bottom: 48px;
}

.faq-item {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
  overflow: hidden;
}

.faq-question {
  padding: 16px 24px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  position: relative;
  list-style: none;
  transition: background-color 0.2s ease;
}

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

.faq-question::after {
  content: "+";
  position: absolute;
  right: 24px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 18px;
  color: var(--color-accent);
  transition: transform 0.2s ease;
}

.faq-item[open] .faq-question {
  background-color: rgba(62, 107, 93, 0.06);
}

.faq-item[open] .faq-question::after {
  transform: translateY(-50%) rotate(45deg);
}

.faq-answer {
  padding: 0 24px 20px;
  font-size: 14px;
  color: var(--color-text-secondary);
}

.escalation-note {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 32px;
}

.escalation-content p {
  font-size: 14px;
  color: var(--color-text-secondary);
}

/* ---------- standards.html ---------- */

.principles-summary {
  margin-bottom: 48px;
}

.work-method {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 40px;
  align-items: start;
  margin-bottom: 48px;
}

.work-method-copy {
  min-width: 0;
}

.method-steps {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin-top: 24px;
}

.method-item {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 20px 24px;
}

.method-item h3 {
  font-size: 15px;
  margin-bottom: 6px;
}

.method-item p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin: 0;
}

.work-method-media {
  margin: 0;
}

.work-method-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: var(--radius-md);
}

.work-method-media figcaption {
  font-size: 13px;
  color: var(--color-text-secondary);
  margin-top: 10px;
}

.quality-boundary {
  margin-bottom: 48px;
}

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

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

.boundary-list li {
  font-size: 14px;
  color: var(--color-text-secondary);
  padding: 10px 0 10px 24px;
  position: relative;
  border-bottom: 1px solid var(--color-border);
}

.boundary-list li::before {
  content: "·";
  position: absolute;
  left: 8px;
  font-size: 18px;
  color: var(--color-accent);
}

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

.related-card {
  padding: 24px;
  transition: border-color 0.2s ease;
}

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

.related-card h3 {
  font-size: 15px;
  margin-bottom: 8px;
}

.related-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin: 0;
}

/* ---------- support.html ---------- */

.support-section {
  margin-bottom: 48px;
}

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

.suitable-card {
  padding: 24px;
}

.suitable-card h3 {
  font-size: 16px;
  margin-bottom: 8px;
}

.suitable-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin: 0;
}

/* ---------- 404.html ---------- */

.error-main {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 80px 24px 100px;
}

.error-section {
  text-align: center;
  max-width: 560px;
  margin: 0 auto;
}

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

.error-title {
  font-size: 24px;
  margin-bottom: 12px;
}

.error-desc {
  font-size: 15px;
  color: var(--color-text-secondary);
  margin-bottom: 28px;
}

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

.error-return,
.error-index {
  display: inline-block;
  padding: 10px 24px;
  font-size: 15px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
  background-color: var(--color-card);
  color: var(--color-text);
  transition: border-color 0.2s ease, color 0.2s ease;
}

.error-return:hover,
.error-index:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* 无障碍 */

.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;
}

/* ==========================================================================
   responsive
   ========================================================================== */

@media (min-width: 769px) and (max-width: 1024px) {
  .brand-tagline {
    display: inline;
  }

  .nav-list li a {
    padding: 8px 10px;
    font-size: 13px;
  }

  .hero-window-section {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .service-windows {
    grid-template-columns: repeat(3, 1fr);
  }

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

  .category-card-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .layout-shell,
  .sidebar-left {
    grid-template-columns: 200px 1fr;
    gap: 32px;
  }

  .work-method {
    grid-template-columns: 1fr;
  }

  .work-method-media img {
    height: 300px;
  }

  .related-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 768px) {
  .header-shell {
    height: 60px;
    padding: 0 16px;
  }

  .brand-tagline {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }

  .nav-list {
    display: none;
    position: absolute;
    top: 60px;
    left: 0;
    right: 0;
    background-color: var(--color-card);
    border-bottom: 1px solid var(--color-border);
    flex-direction: column;
    padding: 8px 16px 16px;
    z-index: 100;
  }

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

  .nav-list li a {
    padding: 12px 8px;
    font-size: 15px;
    border-bottom: 1px solid var(--color-border);
  }

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

  .global-index-btn {
    margin-left: 8px;
    padding: 6px 12px;
    font-size: 13px;
  }

  .inner-main {
    padding: 24px 16px 48px;
  }

  .home-main {
    padding: 0 16px 48px;
  }

  .page-header {
    margin-bottom: 28px;
  }

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

  .hero-window-section {
    grid-template-columns: 1fr;
    gap: 32px;
    padding: 32px 0;
  }

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

  .hero-visual {
    position: relative;
    height: 200px;
    margin-bottom: 24px;
  }

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

  .service-status-strip {
    grid-template-columns: 1fr;
  }

  .status-item {
    padding: 16px 20px;
  }

  .requirement-list {
    grid-template-columns: 1fr;
  }

  .requirement-row {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }

  .compare-cards {
    grid-template-columns: 1fr;
  }

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

  .cooperation-banner {
    flex-direction: column;
    padding: 28px 24px;
    text-align: center;
  }

  .category-grid {
    grid-template-columns: 1fr 1fr;
    gap: 12px;
  }

  .category-card {
    padding: 16px;
  }

  .requirement-item {
    grid-template-columns: 1fr;
  }

  .requirement-media {
    height: 180px;
  }

  .requirement-content {
    padding: 20px;
  }

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

  .layout-shell,
  .sidebar-left {
    display: block;
  }

  .guide-toc {
    position: static;
    margin-bottom: 24px;
  }

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

  .related-link-list {
    grid-template-columns: 1fr;
  }

  .category-card-grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .path-list {
    grid-template-columns: 1fr;
  }

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

  .work-method-media img {
    height: 220px;
  }

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

  .suitable-grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .footer-shell {
    grid-template-columns: 1fr;
    gap: 32px;
    padding: 32px 16px 24px;
  }

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

@media (max-width: 480px) {
  .route-steps {
    grid-template-columns: 1fr;
  }

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

  .spec-table,
  .comparison-table {
    font-size: 13px;
  }

  .spec-table th,
  .spec-table td,
  .comparison-table th,
  .comparison-table td {
    padding: 10px 12px;
  }

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

  .btn-primary,
  .btn-ghost {
    text-align: center;
  }
}