/* =========================================================
   51吃瓜网址 · 全站样式表
   分组：base / layout / components / pages / responsive
   ========================================================= */

/* ---------------------------------------------------------
   1. base：变量、重置、基础排版
   --------------------------------------------------------- */
:root {
  --bg: #F6F3EC;
  --ink: #1D1B18;
  --ink-soft: #6B625A;
  --primary: #14555B;
  --primary-dark: #0F4348;
  --cat-red: #C25B2E;
  --cat-green: #4A6B3E;
  --cat-blue: #2C4B7C;
  --notice-bg: #FBEEE3;
  --line: #DDD6C9;
  --panel: #FFFDF8;
  --band: #EFEAE0;
  --wrap: 1120px;
  --wrap-legal: 820px;
  --radius: 6px;
}

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

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.75;
  font-variant-numeric: tabular-nums;
}

h1,
h2,
h3,
h4 {
  margin: 0;
  font-weight: 600;
  line-height: 1.35;
  color: var(--ink);
}

h1 {
  font-size: 30px;
}

h2 {
  font-size: 20px;
}

h3 {
  font-size: 17px;
}

h4 {
  font-size: 15px;
}

p {
  margin: 0 0 12px;
}

ul,
ol {
  margin: 0;
  padding: 0;
  list-style: none;
}

dl,
dt,
dd {
  margin: 0;
}

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

figure {
  margin: 0;
}

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

a:hover,
a:focus {
  text-decoration: underline;
}

a:focus-visible,
button:focus-visible,
summary:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
}

button {
  font: inherit;
  color: inherit;
}

figcaption {
  margin-top: 8px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.6;
}

/* ---------------------------------------------------------
   2. layout：骨架容器、页头、页脚、内页外壳
   --------------------------------------------------------- */
.site-body {
  background: var(--bg);
  color: var(--ink);
  min-height: 100%;
}

.site-header {
  background: var(--panel);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 40;
}

.header-inner {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 24px;
  min-height: 64px;
  display: flex;
  align-items: center;
  gap: 24px;
}

.brand {
  flex: none;
  font-size: 18px;
  font-weight: 600;
  color: var(--ink);
  padding: 10px 0;
}

.brand:hover,
.brand:focus {
  color: var(--primary);
  text-decoration: none;
}

.site-nav {
  margin-left: auto;
}

.nav-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 2px;
}

.nav-list li {
  display: block;
}

.nav-list a {
  display: block;
  padding: 10px 12px;
  font-size: 15px;
  color: var(--ink);
  border-bottom: 2px solid transparent;
  white-space: nowrap;
}

.nav-list a:hover,
.nav-list a:focus {
  color: var(--primary);
  border-bottom-color: var(--line);
  text-decoration: none;
}

.nav-list a.is-current {
  color: #FFFFFF;
  background: var(--primary);
  border-bottom-color: var(--primary);
}

.nav-toggle {
  display: none;
  margin-left: auto;
  width: 44px;
  height: 44px;
  padding: 0;
  background: none;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  cursor: pointer;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
}

.nav-toggle-bar {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--ink);
}

.mobile-nav {
  display: none;
  background: var(--panel);
  border-top: 1px solid var(--line);
}

.mobile-nav-list {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 8px 24px 16px;
}

.mobile-nav-list li {
  border-bottom: 1px solid var(--line);
}

.mobile-nav-list a {
  display: block;
  padding: 14px 0;
  min-height: 48px;
  color: var(--ink);
  font-size: 16px;
}

.mobile-nav-list a:hover,
.mobile-nav-list a:focus {
  color: var(--primary);
  text-decoration: none;
}

.mobile-nav-note {
  display: block;
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.6;
}

.site-main {
  display: block;
}

.inner-main {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 24px 24px 56px;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--ink-soft);
  margin-bottom: 16px;
}

.breadcrumb a {
  color: var(--ink-soft);
}

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

.breadcrumb-sep {
  color: var(--line);
}

.breadcrumb-current {
  color: var(--ink);
}

.page-header {
  margin-bottom: 16px;
}

.page-title {
  font-size: 30px;
  font-weight: 600;
  color: var(--ink);
}

.site-footer {
  background: var(--band);
  border-top: 1px solid var(--line);
  margin-top: 32px;
}

.footer-inner {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 40px 24px 24px;
}

.footer-cols {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 32px;
}

.footer-col-brand .footer-brand {
  font-size: 17px;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 8px;
}

.footer-col-brand .footer-desc {
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
  max-width: 34em;
}

.footer-col-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 10px;
}

.footer-links li {
  margin-bottom: 6px;
}

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

.footer-links a:hover,
.footer-links a:focus {
  color: var(--primary);
}

.footer-bottom {
  margin-top: 28px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px 24px;
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.7;
}

.footer-bottom p {
  margin: 0;
}

/* ---------------------------------------------------------
   3. components：通用区块、字段表、提示条、入口、折叠问答
   --------------------------------------------------------- */
.section,
.content-section,
.section-block,
.faq-group,
.services-overview,
.service-combos,
.service-exclusions,
.section-stages,
.section-materials,
.section-changes,
.section-diff,
.section-notfit,
.section-next,
.about-scope,
.about-method,
.about-contact,
.next-steps,
.next-step,
.next-entry,
.related-links {
  margin-top: 48px;
}

.section-head {
  margin-bottom: 20px;
}

.section-head h2,
.section-title {
  font-size: 20px;
  font-weight: 600;
}

.section-desc,
.section-lead,
.section-intro,
.section-note,
.faq-group-desc {
  margin-top: 8px;
  color: var(--ink-soft);
  font-size: 15px;
  line-height: 1.75;
  max-width: 78ch;
}

.section-index {
  display: inline-block;
  margin-right: 8px;
  color: var(--cat-blue);
  font-size: 14px;
  font-weight: 600;
}

.section-more {
  margin-top: 16px;
}

.text-link {
  font-size: 15px;
  color: var(--primary);
  border-bottom: 1px solid var(--line);
}

.text-link:hover,
.text-link:focus {
  border-bottom-color: var(--primary);
  text-decoration: none;
}

.section-media,
.content-figure,
.faq-figure,
.scenario-media,
.method-figure,
.process-figure,
.quality-figure,
.stage-figure {
  margin: 20px 0;
}

.section-media img,
.content-figure img,
.faq-figure img,
.scenario-media img,
.method-figure img,
.process-figure img,
.quality-figure img,
.stage-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #E7E1D5;
}

/* 字段化说明 */
.field-list,
.field-table {
  border-top: 1px solid var(--line);
}

.field-list dt,
.field-table .field-name {
  font-size: 14px;
  color: var(--ink-soft);
  font-weight: 400;
  padding-top: 10px;
}

.field-list dd,
.field-table .field-value {
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  color: var(--ink);
}

.field-list dt,
.field-list dd {
  display: block;
}

.field-row {
  display: grid;
  grid-template-columns: 140px minmax(0, 1fr);
  gap: 0 20px;
  border-bottom: 1px solid var(--line);
}

.field-row .field-name,
.field-row dt {
  padding: 12px 0;
  color: var(--ink-soft);
  font-size: 14px;
}

.field-row .field-value,
.field-row dd {
  padding: 12px 0;
  border-bottom: none;
  min-width: 0;
}

/* 提示条 */
.notice-bar,
.boundary-note {
  background: var(--notice-bg);
  border-left: 3px solid var(--cat-red);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 14px 16px;
  margin: 20px 0;
  color: var(--ink);
  font-size: 15px;
}

.notice-bar p,
.boundary-note p {
  margin: 0 0 8px;
}

.notice-bar p:last-child,
.boundary-note p:last-child {
  margin-bottom: 0;
}

.notice-title,
.boundary-note-title {
  font-weight: 600;
}

.notice-list {
  margin-top: 8px;
}

.notice-list li {
  position: relative;
  padding-left: 16px;
  margin-bottom: 4px;
}

.notice-list li::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 0.75em;
  width: 5px;
  height: 1px;
  background: var(--cat-red);
}

.trailing-note {
  color: var(--ink-soft);
  font-size: 14px;
}

/* 通用条目列表 */
.exclusion-list,
.notfit-list,
.change-list,
.diff-list,
.standard-list,
.quality-list,
.check-list {
  border-top: 1px solid var(--line);
}

.exclusion-list li,
.notfit-item,
.diff-item,
.standard-item,
.quality-item,
.check-item {
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.exclusion-list li {
  position: relative;
  padding-left: 18px;
}

.exclusion-list li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 1.55em;
  width: 8px;
  height: 1px;
  background: var(--cat-red);
}

.diff-item h3,
.notfit-item h3,
.standard-item h3,
.quality-item h3,
.change-item h3 {
  margin-bottom: 6px;
}

.diff-item p,
.notfit-item p,
.standard-item p,
.quality-item p,
.change-item p {
  color: var(--ink-soft);
  margin: 0;
}

.check-list {
  counter-reset: checknum;
}

.check-item {
  position: relative;
  padding-left: 34px;
}

.check-item::before {
  counter-increment: checknum;
  content: counter(checknum);
  position: absolute;
  left: 0;
  top: 16px;
  width: 20px;
  height: 20px;
  line-height: 20px;
  text-align: center;
  font-size: 12px;
  color: #FFFFFF;
  background: var(--cat-blue);
  border-radius: 2px;
}

/* 下一步入口 */
.next-steps,
.next-step,
.next-entry,
.section-next {
  border-top: 1px solid var(--line);
  padding-top: 28px;
}

.next-grid,
.next-links,
.next-step-list,
.next-step-grid,
.next-entry-list,
.cta-entries {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-top: 16px;
}

.next-card,
.next-link,
.next-step-item,
.next-step-card,
.next-entry-item,
.cta-entry,
.next-item {
  display: block;
  padding: 16px 18px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--ink);
}

.next-card:hover,
.next-link:hover,
.next-step-item:hover,
.next-step-card:hover,
.next-entry-item:hover,
.cta-entry:hover {
  border-color: var(--primary);
  text-decoration: none;
}

.next-card-title,
.next-card-name,
.next-link-title,
.next-step-name,
.next-entry-title,
.cta-entry-title,
.next-name {
  display: block;
  font-size: 17px;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 4px;
}

.next-card-desc,
.next-link-desc,
.next-step-desc,
.next-entry-desc,
.cta-entry-desc,
.next-desc {
  display: block;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

/* 相关内容条 */
.related-links {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 16px;
  padding: 14px 16px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.related-links-label {
  color: var(--ink-soft);
  font-size: 14px;
}

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

/* 折叠问答 */
.faq-list {
  border-top: 1px solid var(--line);
}

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

.faq-question {
  position: relative;
  padding: 16px 40px 16px 0;
  font-size: 17px;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
}

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

.faq-question::after {
  content: "+";
  position: absolute;
  right: 6px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--primary);
  font-size: 20px;
  line-height: 1;
}

.faq-item[open] .faq-question::after {
  content: "–";
}

.faq-answer {
  padding: 0 0 16px;
  color: var(--ink-soft);
}

.faq-answer p {
  margin: 0 0 10px;
}

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

.faq-link a {
  font-size: 14px;
}

/* 按钮 */
.btn {
  display: inline-block;
  padding: 11px 20px;
  border-radius: var(--radius);
  font-size: 15px;
  border: 1px solid transparent;
  min-height: 44px;
  line-height: 1.4;
}

.btn:hover,
.btn:focus {
  text-decoration: none;
}

.btn-primary {
  background: var(--primary);
  color: #FFFFFF;
  border-color: var(--primary);
}

.btn-primary:hover,
.btn-primary:focus {
  background: var(--primary-dark);
  border-color: var(--primary-dark);
}

.btn-ghost {
  background: transparent;
  color: var(--primary);
  border-color: var(--primary);
}

.btn-ghost:hover,
.btn-ghost:focus {
  background: rgba(20, 85, 91, 0.08);
}

/* 侧栏：主内容在前，aside 在后 */
.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 2fr) minmax(0, 1fr);
  gap: 40px;
  align-items: start;
  margin-top: 32px;
}

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

.page-aside,
.content-aside {
  min-width: 0;
  padding: 18px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.aside-title {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 12px;
}

.aside-links li {
  border-top: 1px solid var(--line);
}

.aside-links li:first-child {
  border-top: none;
}

.aside-links a {
  display: block;
  padding: 10px 0;
  font-size: 15px;
}

.aside-note {
  display: block;
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.6;
}

/* ---------------------------------------------------------
   4. pages：首页
   --------------------------------------------------------- */
.home-main {
  display: block;
}

.hero {
  border-bottom: 1px solid var(--line);
  background: var(--panel);
}

.hero-inner {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 48px 24px 40px;
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
  gap: 40px;
  align-items: start;
}

.hero-copy {
  min-width: 0;
}

.hero-eyebrow {
  margin: 0 0 10px;
  color: var(--cat-red);
  font-size: 14px;
  font-weight: 600;
}

.hero-copy h1 {
  font-size: 36px;
  font-weight: 600;
  line-height: 1.3;
  margin-bottom: 16px;
}

.hero-lead {
  color: var(--ink-soft);
  font-size: 16px;
  line-height: 1.8;
  max-width: 44em;
}

.hero-points {
  margin: 20px 0 24px;
  border-top: 1px solid var(--line);
}

.hero-points li {
  position: relative;
  padding: 10px 0 10px 18px;
  border-bottom: 1px solid var(--line);
  font-size: 15px;
}

.hero-points li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 1.35em;
  width: 8px;
  height: 1px;
  background: var(--primary);
}

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

.hero-side {
  min-width: 0;
}

.hero-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #E7E1D5;
}

.boundary-card {
  margin-top: 20px;
  padding: 16px 18px;
  background: var(--notice-bg);
  border-left: 3px solid var(--cat-red);
  border-radius: 0 var(--radius) var(--radius) 0;
}

.boundary-title {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 8px;
}

.boundary-card p {
  color: var(--ink);
  font-size: 15px;
  margin-bottom: 10px;
}

/* 快捷索引条 */
.quick-index {
  position: sticky;
  top: 64px;
  z-index: 30;
  background: var(--band);
  border-bottom: 1px solid var(--line);
}

.quick-index-list {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 4px 8px;
}

.quick-index-list a {
  display: block;
  padding: 12px 10px;
  font-size: 15px;
  color: var(--ink);
  border-bottom: 2px solid transparent;
}

.quick-index-list a:hover,
.quick-index-list a:focus {
  color: var(--primary);
  border-bottom-color: var(--primary);
  text-decoration: none;
}

.section-services,
.section-scenarios,
.section-process,
.section-quality,
.section-faq,
.section-cta {
  width: 100%;
  max-width: var(--wrap);
  margin-left: auto;
  margin-right: auto;
  padding: 0 24px;
}

/* 服务条目总览表 */
.service-rows {
  border-top: 1px solid var(--line);
}

.service-row {
  display: grid;
  grid-template-columns: 4px minmax(0, 1fr) 180px;
  gap: 0 18px;
  align-items: start;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

.cat-mark {
  display: block;
  width: 4px;
  height: 100%;
  min-height: 28px;
  background: var(--cat-red);
  border-radius: 2px;
}

.service-row-main {
  min-width: 0;
}

.service-name {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 4px;
}

.service-note {
  margin: 0;
  color: var(--ink-soft);
  font-size: 15px;
}

.service-deliver {
  margin: 0;
  padding-top: 2px;
  color: var(--ink-soft);
  font-size: 14px;
  text-align: right;
}

/* 适用场景分组 */
.scenario-groups {
  display: grid;
  gap: 24px;
}

.scenario-group {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr);
  gap: 24px;
  align-items: start;
  padding: 20px 0;
  border-top: 1px solid var(--line);
}

.scenario-copy {
  min-width: 0;
}

.scenario-name {
  position: relative;
  padding-left: 14px;
  margin-bottom: 10px;
  font-size: 17px;
  font-weight: 600;
}

.scenario-name::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.35em;
  width: 6px;
  height: 16px;
  background: var(--cat-green);
  border-radius: 2px;
}

.scenario-line {
  color: var(--ink-soft);
  font-size: 15px;
}

.scenario-figure {
  min-width: 0;
}

.scenario-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #E7E1D5;
}

/* 合作流程阶段条 */
.stage-list {
  border-top: 1px solid var(--line);
}

.section-process .stage-item {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 0 16px;
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
}

.section-process .stage-num {
  grid-row: 1 / span 3;
  font-size: 20px;
  font-weight: 600;
  color: var(--cat-blue);
  line-height: 1.4;
}

.section-process .stage-name {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 8px;
}

.stage-body {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-bottom: 8px;
}

.stage-col {
  min-width: 0;
}

.stage-col-title {
  font-size: 14px;
  color: var(--ink-soft);
  font-weight: 600;
  margin-bottom: 4px;
}

.stage-col p {
  margin: 0;
  font-size: 15px;
}

.section-process .stage-meta {
  margin: 0;
  color: var(--ink-soft);
  font-size: 14px;
}

/* 交付与协作标准区 */
.quality-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 0.6fr);
  gap: 32px;
  align-items: start;
}

.quality-list {
  min-width: 0;
}

.quality-figure {
  min-width: 0;
  margin: 0;
}

.quality-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #E7E1D5;
}

/* 首页 CTA */
.cta-entry {
  border-left: 3px solid var(--primary);
}

/* ---------------------------------------------------------
   5. pages：内页模块
   --------------------------------------------------------- */
/* 内页标题区 */
.page-hero {
  margin-bottom: 8px;
}

.page-hero-inner {
  min-width: 0;
}

.page-hero-cat,
.page-hero-mark {
  display: inline-block;
  margin: 0 0 8px;
  color: var(--cat-red);
  font-size: 14px;
  font-weight: 600;
}

.page-hero-mark--legal {
  color: var(--cat-blue);
}

.page-hero-bar,
.page-head-bar {
  display: inline-block;
  width: 32px;
  height: 3px;
  margin-bottom: 10px;
  background: var(--cat-blue);
  border-radius: 2px;
}

.page-hero-desc,
.page-hero-lead,
.page-hero-note,
.page-head-desc {
  margin: 0;
  color: var(--ink-soft);
  font-size: 15px;
  line-height: 1.75;
  max-width: 78ch;
}

.page-head {
  margin-bottom: 24px;
}

/* 服务范围页 */
.services-overview .service-item {
  padding: 20px 0;
  border-bottom: 1px solid var(--line);
}

.services-overview .service-item h3 {
  margin: 8px 0 10px;
  font-size: 17px;
}

.tag {
  display: inline-block;
  padding: 2px 8px;
  font-size: 12px;
  border-radius: 2px;
  background: var(--notice-bg);
  color: var(--cat-red);
}

.tag-red {
  border-left: 3px solid var(--cat-red);
}

.combo-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
  margin-top: 16px;
}

.combo-col {
  min-width: 0;
  padding: 16px 18px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-top: 3px solid var(--cat-blue);
  border-radius: var(--radius);
}

.combo-col h3 {
  margin-bottom: 8px;
}

.combo-col p {
  color: var(--ink-soft);
  font-size: 15px;
}

.combo-list {
  margin-top: 10px;
}

.combo-list li {
  position: relative;
  padding-left: 16px;
  margin-bottom: 4px;
  font-size: 14px;
  color: var(--ink-soft);
}

.combo-list li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 0.8em;
  width: 6px;
  height: 1px;
  background: var(--cat-blue);
}

/* 适用场景页 */
.scenario-block {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr);
  gap: 28px;
  align-items: start;
  padding: 24px 0;
  border-top: 1px solid var(--line);
}

.scenario-body {
  min-width: 0;
}

.scenario-body h3 {
  position: relative;
  padding-left: 14px;
  margin-bottom: 12px;
  font-size: 17px;
  font-weight: 600;
}

.scenario-body h3::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.35em;
  width: 6px;
  height: 16px;
  background: var(--cat-green);
  border-radius: 2px;
}

.scenario-media {
  min-width: 0;
  margin: 0;
}

.scenario-media img {
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #E7E1D5;
}

/* 合作流程页 */
.section-stages .stage-item {
  border-top: 1px solid var(--line);
}

.stage-card {
  display: grid;
  grid-template-columns: 60px minmax(0, 1fr);
  gap: 0 20px;
  padding: 22px 0;
  border-bottom: 1px solid var(--line);
}

.stage-index {
  grid-row: 1 / span 3;
  margin: 0;
  font-size: 15px;
  font-weight: 600;
  color: var(--cat-blue);
  line-height: 1.6;
}

.stage-card .stage-name {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 10px;
}

.stage-card .stage-body {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  margin-bottom: 10px;
}

.stage-card .stage-col {
  min-width: 0;
}

.stage-card .stage-col h4 {
  font-size: 14px;
  color: var(--ink-soft);
  margin-bottom: 4px;
}

.stage-card .stage-col p {
  margin: 0;
  font-size: 15px;
}

.stage-card .stage-meta {
  display: grid;
  grid-template-columns: 88px minmax(0, 1fr);
  gap: 4px 16px;
  font-size: 14px;
}

.stage-card .stage-meta dt {
  color: var(--ink-soft);
}

.stage-card .stage-meta dd {
  color: var(--ink);
}

.material-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
  margin-top: 16px;
}

.material-item {
  min-width: 0;
  padding: 16px 18px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.material-name {
  margin-bottom: 6px;
}

.material-desc {
  color: var(--ink-soft);
  font-size: 15px;
}

.material-points {
  margin-top: 10px;
  border-top: 1px solid var(--line);
  padding-top: 8px;
}

.material-points li {
  position: relative;
  padding-left: 16px;
  margin-bottom: 4px;
  font-size: 14px;
  color: var(--ink-soft);
}

.material-points li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 0.8em;
  width: 6px;
  height: 1px;
  background: var(--cat-green);
}

/* 交付与协作标准页 */
.page-quality .field-table {
  margin-top: 16px;
  border-top: 1px solid var(--line);
}

.page-quality .field-row {
  grid-template-columns: 160px minmax(0, 1fr);
}

.page-quality .field-name {
  padding: 12px 0;
  color: var(--ink-soft);
  font-size: 14px;
}

.page-quality .field-value {
  padding: 12px 0;
  border-bottom: none;
}

.page-quality .content-figure img {
  aspect-ratio: 16 / 9;
}

/* 常见问题页 */
.page-faq .faq-body {
  margin-top: 8px;
}

.page-faq .faq-group {
  margin-top: 40px;
}

.page-faq .faq-group:first-child {
  margin-top: 0;
}

.page-faq .faq-group-head {
  margin-bottom: 12px;
}

.page-faq .faq-figure img {
  aspect-ratio: 16 / 9;
}

/* 关于我们页 */
.content-shell {
  margin-top: 8px;
}

.about-scope .scope-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
  margin-top: 16px;
}

.scope-col {
  min-width: 0;
  padding: 18px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.scope-col-do {
  border-top: 3px solid var(--cat-green);
}

.scope-col-dont {
  border-top: 3px solid var(--cat-red);
}

.scope-col-title {
  margin-bottom: 10px;
}

.scope-list {
  border-top: 1px solid var(--line);
}

.scope-item {
  position: relative;
  padding: 10px 0 10px 16px;
  border-bottom: 1px solid var(--line);
  font-size: 15px;
}

.scope-item::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 1.25em;
  width: 6px;
  height: 1px;
  background: var(--ink-soft);
}

.scope-col-do .scope-item::before {
  background: var(--cat-green);
}

.scope-col-dont .scope-item::before {
  background: var(--cat-red);
}

.method-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(0, 0.7fr);
  gap: 32px;
  align-items: start;
  margin-top: 16px;
}

.method-list {
  min-width: 0;
  border-top: 1px solid var(--line);
}

.method-item {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 0 16px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

.method-num {
  font-size: 15px;
  font-weight: 600;
  color: var(--cat-blue);
}

.method-body {
  min-width: 0;
}

.method-name {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 4px;
}

.method-desc {
  margin: 0;
  color: var(--ink-soft);
  font-size: 15px;
}

.method-figure {
  min-width: 0;
  margin: 0;
}

.method-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #E7E1D5;
}

.contact-layout {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
  margin-top: 16px;
}

.contact-guide,
.contact-entry {
  min-width: 0;
  padding: 18px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 3px solid var(--cat-blue);
  border-radius: var(--radius);
}

.contact-guide-title,
.contact-entry-title {
  margin-bottom: 10px;
}

.contact-guide-list {
  border-top: 1px solid var(--line);
}

.contact-guide-item {
  position: relative;
  padding: 10px 0 10px 16px;
  border-bottom: 1px solid var(--line);
  font-size: 15px;
}

.contact-guide-item::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 1.25em;
  width: 6px;
  height: 1px;
  background: var(--cat-blue);
}

.contact-entry-desc {
  color: var(--ink-soft);
  font-size: 15px;
}

.contact-entry-links {
  margin-top: 10px;
}

.contact-entry-links li {
  margin-bottom: 6px;
}

/* 隐私与条款页 */
.page-layout.layout-legal {
  grid-template-columns: minmax(0, 2fr) minmax(0, 1fr);
}

.page-privacy .content-section {
  margin-top: 32px;
}

.page-privacy .content-section:first-child {
  margin-top: 0;
}

.page-privacy .content-section h2 {
  margin-bottom: 10px;
}

.page-privacy .content-section .field-table {
  margin-top: 12px;
}

.page-privacy .content-section .field-row {
  grid-template-columns: 150px minmax(0, 1fr);
}

.page-privacy .content-section .field-row dt {
  padding: 12px 0;
  color: var(--ink-soft);
  font-size: 14px;
}

.page-privacy .content-section .field-row dd {
  padding: 12px 0;
}

.page-privacy .content-figure img {
  aspect-ratio: 16 / 9;
}

/* 辅助功能声明页 */
.page-accessibility .section-block {
  margin-top: 40px;
}

.page-accessibility .section-block:first-of-type {
  margin-top: 24px;
}

.page-accessibility .field-table {
  margin-top: 14px;
}

.page-accessibility .field-row {
  grid-template-columns: 150px minmax(0, 1fr);
}

.page-accessibility .field-name {
  padding: 12px 0;
  color: var(--ink-soft);
  font-size: 14px;
}

.page-accessibility .field-value {
  padding: 12px 0;
}

.page-accessibility .content-figure img {
  aspect-ratio: 16 / 9;
}

.page-accessibility .section-text {
  color: var(--ink-soft);
  font-size: 15px;
  max-width: 78ch;
}

/* 404 */
.error-main {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 56px 24px 64px;
}

.error-hero {
  border-bottom: 1px solid var(--line);
  padding-bottom: 32px;
}

.error-inner {
  min-width: 0;
}

.error-code {
  margin: 0 0 8px;
  color: var(--cat-red);
  font-size: 14px;
  font-weight: 600;
}

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

.error-text {
  color: var(--ink-soft);
  max-width: 60ch;
  margin-bottom: 20px;
}

.error-home-link {
  display: inline-block;
  min-height: 44px;
  padding: 11px 20px;
  background: var(--primary);
  color: #FFFFFF;
  border-radius: var(--radius);
}

.error-home-link:hover,
.error-home-link:focus {
  background: var(--primary-dark);
  text-decoration: none;
}

.error-paths {
  margin-top: 32px;
}

.error-paths-title {
  margin-bottom: 12px;
}

.error-paths-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.error-path-item {
  min-width: 0;
  padding: 16px 18px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.error-path-item a {
  display: block;
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 4px;
}

.error-path-item p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 14px;
}

/* ---------------------------------------------------------
   6. responsive：900px / 600px 断点
   --------------------------------------------------------- */
@media (max-width: 900px) {
  .header-inner {
    padding: 0 18px;
    gap: 12px;
  }

  .nav-toggle {
    display: flex;
  }

  .nav-list {
    display: none;
  }

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

  .mobile-nav.is-open {
    display: block;
  }

  .mobile-nav-list {
    padding: 8px 18px 16px;
  }

  .inner-main {
    padding: 20px 18px 48px;
  }

  .hero-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 28px;
    padding: 32px 18px 28px;
  }

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

  .quick-index {
    position: static;
  }

  .quick-index-list {
    padding: 0 18px;
    flex-wrap: nowrap;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }

  .quick-index-list li {
    flex: none;
  }

  .section-services,
  .section-scenarios,
  .section-process,
  .section-quality,
  .section-faq,
  .section-cta {
    padding: 0 18px;
  }

  .service-row {
    grid-template-columns: 4px minmax(0, 1fr);
    gap: 0 14px;
  }

  .service-deliver {
    grid-column: 2 / -1;
    text-align: left;
    margin-top: 6px;
  }

  .scenario-group,
  .scenario-block {
    grid-template-columns: minmax(0, 1fr);
    gap: 16px;
  }

  .stage-body,
  .stage-card .stage-body {
    grid-template-columns: minmax(0, 1fr);
    gap: 12px;
  }

  .quality-layout,
  .method-layout {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
  }

  .quality-figure img,
  .method-figure img {
    aspect-ratio: 16 / 9;
  }

  .combo-grid,
  .material-grid,
  .error-paths-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-layout,
  .page-layout.layout-legal {
    grid-template-columns: minmax(0, 1fr);
    gap: 28px;
  }

  .page-aside,
  .content-aside {
    padding: 14px 16px;
  }

  .aside-links {
    display: flex;
    flex-wrap: wrap;
    gap: 8px 20px;
  }

  .aside-links li {
    border-top: none;
  }

  .aside-links a {
    padding: 6px 0;
  }

  .footer-cols {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px;
  }

  .footer-col-brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 600px) {
  body {
    font-size: 15px;
  }

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

  .hero-copy h1 {
    font-size: 24px;
  }

  .header-inner {
    padding: 0 14px;
    min-height: 58px;
  }

  .inner-main,
  .error-main {
    padding-left: 14px;
    padding-right: 14px;
  }

  .hero-inner {
    padding: 24px 14px 24px;
  }

  .section-services,
  .section-scenarios,
  .section-process,
  .section-quality,
  .section-faq,
  .section-cta {
    padding: 0 14px;
  }

  .quick-index-list {
    padding: 0 14px;
  }

  .next-grid,
  .next-links,
  .next-step-list,
  .next-step-grid,
  .next-entry-list,
  .cta-entries,
  .combo-grid,
  .material-grid,
  .about-scope .scope-grid,
  .contact-layout,
  .error-paths-list {
    grid-template-columns: minmax(0, 1fr);
  }

  .field-row,
  .page-quality .field-row,
  .page-privacy .content-section .field-row,
  .page-accessibility .field-row {
    grid-template-columns: minmax(0, 1fr);
    gap: 0;
  }

  .field-row dt,
  .field-row .field-name {
    padding-bottom: 0;
  }

  .stage-card {
    grid-template-columns: minmax(0, 1fr);
    gap: 0;
  }

  .stage-index {
    grid-row: auto;
    margin-bottom: 4px;
  }

  .stage-card .stage-meta {
    grid-template-columns: minmax(0, 1fr);
    gap: 0;
  }

  .stage-card .stage-meta dd {
    margin-bottom: 6px;
  }

  .section-process .stage-item {
    grid-template-columns: 32px minmax(0, 1fr);
    gap: 0 12px;
  }

  .footer-cols {
    grid-template-columns: minmax(0, 1fr);
    gap: 20px;
  }

  .footer-bottom {
    flex-direction: column;
  }
}

/* ---------------------------------------------------------
   7. 打印与动效偏好
   --------------------------------------------------------- */
@media print {
  .site-header,
  .quick-index,
  .nav-toggle,
  .mobile-nav,
  .next-steps,
  .next-step,
  .next-entry,
  .related-links {
    display: none;
  }

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

  .site-footer {
    background: #FFFFFF;
    border-top: 1px solid #999999;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    transition-duration: 0.001ms !important;
  }
}