/* =========================================================
   国产吃瓜 nongchengjiancai.com
   全站样式表
   分组：base / layout / components / pages / responsive
   ========================================================= */

/* ---------------------------------------------------------
   base · 变量与基础排版
   --------------------------------------------------------- */

:root {
  --ink: #17202b;
  --ink-soft: #5b6470;
  --brand: #1b3a5c;
  --brand-deep: #12283f;
  --accent: #b8552f;
  --paper: #f6f5f2;
  --surface: #ffffff;
  --line: #d9d6cf;
  --line-soft: #e8e5de;

  --font-sans: "Source Han Sans SC", "Noto Sans SC", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --font-mono: "SFMono-Regular", "Menlo", "Consolas", "Liberation Mono", monospace;

  --wrap: 1120px;
  --wrap-narrow: 900px;
  --wrap-read: 760px;
  --aside-w: 240px;

  --header-h: 76px;
  --header-h-tight: 58px;
}

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

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

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.75;
  font-weight: 400;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

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

h1 {
  font-size: 30px;
}

h2 {
  font-size: 22px;
}

h3 {
  font-size: 17px;
}

h4 {
  font-size: 15px;
}

p {
  margin: 0 0 1.1em;
}

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

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

dl {
  margin: 0;
}

dt,
dd {
  margin: 0;
}

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

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

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

figure {
  margin: 0;
}

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

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* 图片与图注通用约束 */
figure img {
  width: 100%;
  height: auto;
  object-fit: cover;
  background: var(--line-soft);
  border: 1px solid var(--line);
  border-radius: 6px;
}

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

/* ---------------------------------------------------------
   layout · 页头骨架
   --------------------------------------------------------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: var(--surface);
  border-bottom: 1px solid var(--line);
  transition: box-shadow 0.2s ease;
}

.site-header.is-tight {
  box-shadow: 0 1px 0 rgba(23, 32, 43, 0.06), 0 6px 18px rgba(23, 32, 43, 0.06);
}

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

.site-header.is-tight .header-inner {
  min-height: var(--header-h-tight);
}

.brand {
  display: flex;
  flex-direction: column;
  gap: 2px;
  flex: 0 0 auto;
  color: var(--ink);
}

.brand:hover,
.brand:focus-visible {
  color: var(--ink);
}

.brand-name {
  font-size: 20px;
  font-weight: 600;
  line-height: 1.2;
  color: var(--brand);
}

.brand-tag {
  font-size: 12px;
  line-height: 1.4;
  color: var(--ink-soft);
  transition: opacity 0.2s ease, max-height 0.2s ease;
}

.site-header.is-tight .brand-tag {
  opacity: 0;
  max-height: 0;
  overflow: hidden;
}

.site-nav {
  flex: 1 1 auto;
  display: flex;
  justify-content: flex-end;
}

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

.site-nav a {
  display: block;
  padding: 8px 12px;
  color: var(--ink);
  font-size: 15px;
  line-height: 1.5;
  border-bottom: 2px solid transparent;
}

.site-nav a:hover,
.site-nav a:focus-visible {
  color: var(--brand);
  border-bottom-color: var(--line);
}

.site-nav a.is-current {
  color: var(--brand);
  font-weight: 600;
  border-bottom-color: var(--brand);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 0 10px;
  margin-left: auto;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--surface);
}

.nav-toggle-bar {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--ink);
}

/* ---------------------------------------------------------
   layout · 主区与容器
   --------------------------------------------------------- */

.site-main {
  display: block;
}

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

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

.page-layout {
  display: block;
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 24px 56px;
}

.page-layout.layout-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr) var(--aside-w);
  gap: 48px;
  align-items: start;
}

.page-layout.layout-shell .inner-main {
  max-width: var(--wrap-read);
  margin: 0;
  padding: 0;
}

/* 左侧栏：aside 先于 main 出现在 DOM 中 */
.sidebar-left .page-layout,
.page-layout.sidebar-left {
  display: grid;
  grid-template-columns: var(--aside-w) minmax(0, 1fr);
  gap: 48px;
  align-items: start;
}

.sidebar-left .page-layout .inner-main,
.page-layout.sidebar-left .inner-main {
  max-width: var(--wrap-read);
  margin: 0;
  padding: 0;
}

/* ---------------------------------------------------------
   layout · 面包屑与页标题区
   --------------------------------------------------------- */

.breadcrumb {
  padding: 20px 0 0;
}

.page-layout > .breadcrumb,
.page-layout .inner-main > .breadcrumb {
  padding: 20px 0 0;
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--ink-soft);
}

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

.breadcrumb a:hover,
.breadcrumb a:focus-visible {
  color: var(--accent);
  text-decoration: underline;
}

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

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

.page-header {
  padding: 14px 0 0;
}

.page-title {
  font-size: 30px;
  font-weight: 600;
  line-height: 1.3;
  color: var(--ink);
}

.page-title + .page-title,
.page-header + .page-title {
  padding-top: 8px;
}

.page-title p,
.page-lead,
.page-desc,
.page-title-lead {
  margin: 10px 0 0;
  max-width: 62ch;
  color: var(--ink-soft);
  font-size: 15px;
  line-height: 1.75;
}

.page-scope,
.page-title-scope {
  margin: 8px 0 0;
  max-width: 62ch;
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.6;
}

.page-title-inner {
  padding: 0 0 4px;
}

section.page-title {
  padding: 0 0 28px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 32px;
}

/* ---------------------------------------------------------
   layout · 页脚
   --------------------------------------------------------- */

.site-footer {
  margin-top: 24px;
  background: var(--surface);
  border-top: 1px solid var(--line);
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 28px;
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 20px 24px;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 2px;
  flex: 0 0 auto;
}

.footer-name {
  font-size: 15px;
  font-weight: 600;
  color: var(--brand);
}

.footer-slogan {
  font-size: 13px;
  color: var(--ink-soft);
}

.footer-nav {
  flex: 1 1 auto;
}

.footer-nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 20px;
}

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

.footer-nav a:hover,
.footer-nav a:focus-visible {
  color: var(--accent);
  text-decoration: underline;
}

.footer-note {
  flex: 1 1 240px;
  margin: 0;
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.6;
}

.footer-copy {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 24px 20px;
  color: var(--ink-soft);
  font-size: 13px;
}

/* ---------------------------------------------------------
   components · 通用文本与链接
   --------------------------------------------------------- */

.section-title {
  font-size: 22px;
  font-weight: 600;
  color: var(--ink);
}

.section-intro {
  margin: 10px 0 0;
  max-width: 66ch;
  color: var(--ink-soft);
  font-size: 15px;
}

.text-link {
  color: var(--brand);
  font-size: 14px;
  border-bottom: 1px solid var(--line);
  padding-bottom: 1px;
}

.text-link:hover,
.text-link:focus-visible {
  color: var(--accent);
  border-bottom-color: var(--accent);
  font-weight: 600;
}

.more-link-row {
  margin: 24px 0 0;
}

.table-footnote,
.block-note {
  margin: 14px 0 0;
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.65;
}

/* ---------------------------------------------------------
   components · 按钮
   --------------------------------------------------------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 22px;
  border-radius: 6px;
  font-size: 15px;
  font-weight: 600;
  line-height: 1.4;
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--brand-deep);
  color: #fff;
  border-color: var(--brand-deep);
}

.btn-primary:hover,
.btn-primary:focus-visible {
  background: var(--brand);
  border-color: var(--brand);
  color: #fff;
}

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

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

/* ---------------------------------------------------------
   components · 表格
   --------------------------------------------------------- */

.table-wrap {
  margin-top: 22px;
  width: 100%;
  overflow-x: auto;
}

.data-table,
.compare-table,
.spec-table {
  width: 100%;
  min-width: 560px;
  background: var(--surface);
  border: 1px solid var(--line);
  font-size: 14px;
}

.data-table caption,
.compare-table caption,
.spec-table caption {
  text-align: left;
  color: var(--ink-soft);
  font-size: 13px;
  padding-bottom: 8px;
}

.data-table th,
.data-table td,
.compare-table th,
.compare-table td,
.spec-table th,
.spec-table td {
  padding: 12px 14px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--line-soft);
  line-height: 1.65;
}

.data-table thead th,
.compare-table thead th,
.spec-table thead th {
  background: #f0efeb;
  color: var(--brand);
  font-weight: 600;
  border-bottom: 1px solid var(--line);
  white-space: nowrap;
}

.data-table tbody tr:hover,
.compare-table tbody tr:hover,
.spec-table tbody tr:hover {
  background: #faf9f6;
}

.data-table tbody tr:last-child td,
.compare-table tbody tr:last-child td,
.spec-table tbody tr:last-child td {
  border-bottom: 0;
}

.data-table td:first-child,
.compare-table td:first-child,
.spec-table td:first-child {
  font-weight: 600;
  color: var(--ink);
}

/* 等宽数字用于编号列 */
.data-table td:first-child,
.compare-table td:first-child,
.spec-table td:first-child,
.step-no,
.step-num,
.step-index,
.index-num,
.process-no {
  font-variant-numeric: tabular-nums;
}

/* ---------------------------------------------------------
   components · 步骤编号条（首页 / 内页各自限定）
   --------------------------------------------------------- */

.step-row,
.process-row,
.step-bar,
.step-list,
.revision-steps {
  display: grid;
  gap: 18px;
  margin-top: 22px;
}

/* 首页观察方法预览：三步 */
.step-row {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.step-row .step-item {
  padding: 18px 18px 20px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.step-row .step-no {
  display: block;
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
}

.step-row .step-item h3 {
  margin-top: 8px;
}

.step-row .step-item p {
  margin: 8px 0 0;
  color: var(--ink-soft);
  font-size: 14px;
}

/* 首页合作流程五步 */
.process-row {
  grid-template-columns: repeat(5, minmax(0, 1fr));
}

.process-row .process-item {
  padding: 16px 14px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.process-row .process-no {
  display: block;
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
}

.process-row .process-item h3 {
  margin-top: 8px;
  font-size: 16px;
}

.process-row .process-item p {
  margin: 6px 0 0;
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.65;
}

/* 观察方法页：四步纵向列表 */
.step-list {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.step-list .step-item {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 4px 14px;
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.step-list .step-num {
  grid-row: 1 / span 2;
  color: var(--accent);
  font-size: 20px;
  font-weight: 600;
  line-height: 1.3;
}

.step-list .step-item h3 {
  margin: 0;
}

.step-list .step-item p {
  margin: 6px 0 0;
  color: var(--ink-soft);
  font-size: 14px;
}

/* 合作流程页：五阶段总览 */
.step-bar {
  grid-template-columns: repeat(5, minmax(0, 1fr));
}

.step-bar .step-item {
  padding: 16px 14px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.step-bar .step-index {
  display: block;
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
}

.step-bar .step-item h3 {
  margin-top: 8px;
  font-size: 16px;
}

.step-bar .step-item p {
  margin: 6px 0 0;
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.65;
}

/* 交付标准页：修改反馈三步 */
.revision-steps {
  grid-template-columns: repeat(3, minmax(0, 1fr));
  counter-reset: revision;
}

.revision-rule .revision-step {
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.revision-rule .revision-step h3 {
  margin: 0 0 8px;
}

.revision-rule .revision-step p {
  color: var(--ink-soft);
  font-size: 14px;
}

/* ---------------------------------------------------------
   components · 内容区块与说明块
   --------------------------------------------------------- */

.home-main section,
.inner-main section,
.page-layout section {
  scroll-margin-top: calc(var(--header-h-tight) + 16px);
}

.content-block {
  padding: 0 0 8px;
  margin-bottom: 40px;
}

.content-block > h2,
.content-block > p {
  margin-top: 0;
}

.content-block > p {
  margin: 10px 0 0;
  color: var(--ink-soft);
}

.content-figure,
.section-figure,
.diagram-figure,
.process-figure,
.page-figure {
  margin-top: 22px;
}

/* ---------------------------------------------------------
   components · 字段列表 / 服务索引 / 列表条目
   --------------------------------------------------------- */

.field-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  margin-top: 22px;
}

.field-item {
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.field-item h3 {
  margin: 0 0 8px;
}

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

.reason-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin-top: 22px;
}

.reason-item {
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: 6px;
}

.reason-item h3 {
  margin: 0 0 8px;
  font-size: 16px;
}

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

.index-list {
  display: grid;
  gap: 10px;
  margin-top: 22px;
}

.index-list a {
  display: grid;
  grid-template-columns: 44px minmax(140px, 0.5fr) minmax(0, 1fr);
  gap: 6px 16px;
  align-items: baseline;
  padding: 14px 16px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
  color: var(--ink);
}

.index-list a:hover,
.index-list a:focus-visible {
  border-color: var(--brand);
  color: var(--ink);
}

.index-list .index-num {
  color: var(--accent);
  font-weight: 600;
}

.index-list .index-name {
  font-weight: 600;
  color: var(--brand);
}

.index-list .index-desc {
  color: var(--ink-soft);
  font-size: 14px;
}

/* 包含项 / 不包含项 */
.boundary-cols,
.boundary-columns {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  margin-top: 22px;
}

.boundary-col {
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.boundary-col h3,
.boundary-col h4 {
  margin: 0 0 12px;
  font-size: 16px;
}

.boundary-include h3,
.boundary-include h4 {
  color: var(--brand);
}

.boundary-exclude h3,
.boundary-exclude h4 {
  color: var(--accent);
}

.boundary-col ul {
  display: grid;
  gap: 8px;
}

.boundary-col li {
  position: relative;
  padding-left: 16px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

.boundary-col li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--line);
}

.boundary-include li::before {
  background: var(--brand);
}

.boundary-exclude li::before {
  background: var(--accent);
}

/* 服务分组（服务矩阵页） */
.service-group {
  margin-top: 28px;
  padding-top: 22px;
  border-top: 1px solid var(--line);
}

.service-group > h3 {
  font-size: 18px;
}

.service-group .boundary-columns {
  margin-top: 16px;
}

/* ---------------------------------------------------------
   components · 侧栏
   --------------------------------------------------------- */

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

.sidebar {
  display: grid;
  gap: 26px;
  align-content: start;
}

.layout-aside {
  display: grid;
  gap: 26px;
  align-content: start;
}

.anchor-nav,
.related-nav {
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.sidebar-title,
.aside-title,
.anchor-nav-title,
.related-nav-title {
  margin: 0 0 12px;
  color: var(--brand);
  font-size: 14px;
  font-weight: 600;
}

.anchor-nav ul,
.related-nav ul {
  display: grid;
  gap: 4px;
}

.anchor-nav a,
.related-nav a {
  display: block;
  padding: 8px 0;
  color: var(--ink);
  font-size: 14px;
  line-height: 1.6;
  border-bottom: 1px solid var(--line-soft);
}

.anchor-nav li:last-child a,
.related-nav li:last-child a {
  border-bottom: 0;
}

.anchor-nav a:hover,
.anchor-nav a:focus-visible,
.related-nav a:hover,
.related-nav a:focus-visible {
  color: var(--accent);
}

.anchor-nav a.is-active {
  color: var(--accent);
  font-weight: 600;
  border-bottom-color: var(--accent);
}

/* ---------------------------------------------------------
   components · 时间列表与清单（合作流程页）
   --------------------------------------------------------- */

.timeline-list {
  display: grid;
  gap: 22px;
  margin-top: 22px;
}

.timeline-group {
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.timeline-date {
  margin: 0 0 12px;
  color: var(--brand);
  font-size: 15px;
  font-weight: 600;
}

.timeline-nodes {
  display: grid;
  gap: 12px;
}

.timeline-node {
  display: grid;
  grid-template-columns: 120px minmax(0, 1fr);
  gap: 4px 16px;
  align-items: baseline;
  padding-top: 12px;
  border-top: 1px solid var(--line-soft);
}

.timeline-node:first-child {
  padding-top: 0;
  border-top: 0;
}

.timeline-node .node-stage {
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
}

.timeline-node p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 14px;
}

.checklist-group {
  margin-top: 28px;
  padding-top: 22px;
  border-top: 1px solid var(--line);
}

.checklist-stage {
  margin: 0 0 14px;
  color: var(--brand);
  font-size: 17px;
}

.checklist-columns {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
}

.checklist-col {
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.checklist-col h4 {
  margin: 0 0 12px;
  font-size: 15px;
  color: var(--ink);
}

.checklist-col ul {
  display: grid;
  gap: 8px;
}

.checklist-col li {
  position: relative;
  padding-left: 16px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

.checklist-col li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--brand);
}

.boundary-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin-top: 22px;
}

.boundary-item {
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: 6px;
}

.boundary-item h3 {
  margin: 0 0 8px;
  font-size: 16px;
}

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

.section-next {
  margin: 26px 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
}

.section-next a {
  color: var(--brand);
  font-size: 14px;
  border-bottom: 1px solid var(--line);
}

.section-next a:hover,
.section-next a:focus-visible {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* ---------------------------------------------------------
   components · 交付清单与规范（交付标准页）
   --------------------------------------------------------- */

.section-head {
  margin-bottom: 18px;
}

.section-head h2 {
  margin: 0;
}

.section-head p {
  margin: 10px 0 0;
  max-width: 66ch;
  color: var(--ink-soft);
  font-size: 15px;
}

.deliverable-list,
.include-exclude-table,
.service-rules,
.revision-rule {
  margin-bottom: 40px;
}

.deliverable-item {
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
  margin-top: 16px;
}

.deliverable-item h3 {
  margin: 0 0 12px;
  font-size: 17px;
  color: var(--brand);
}

.deliverable-meta {
  display: grid;
  grid-template-columns: 96px minmax(0, 1fr);
  gap: 8px 16px;
}

.deliverable-meta dt {
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.7;
}

.deliverable-meta dd {
  color: var(--ink);
  font-size: 14px;
  line-height: 1.7;
}

.rule-list {
  display: grid;
  gap: 14px;
  margin-top: 6px;
}

.rule-item {
  padding: 16px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.rule-item h3 {
  margin: 0 0 8px;
  font-size: 16px;
}

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

/* ---------------------------------------------------------
   components · 答疑（分类入口 + 手风琴）
   --------------------------------------------------------- */

.faq-grid,
.category-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  margin-top: 22px;
}

.faq-cat,
.category-item {
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.faq-cat h3,
.category-item h3 {
  margin: 0 0 8px;
  font-size: 16px;
}

.faq-cat h3 a,
.category-item h3 a {
  color: var(--brand);
}

.faq-cat p,
.category-item p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 14px;
}

.faq-group {
  margin-top: 26px;
}

.faq-group-title {
  margin: 0 0 12px;
  padding-bottom: 8px;
  color: var(--brand);
  font-size: 17px;
  border-bottom: 1px solid var(--line);
}

.faq-item {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
  margin-bottom: 10px;
}

.faq-item summary {
  position: relative;
  padding: 14px 44px 14px 18px;
  color: var(--ink);
  font-size: 15px;
  font-weight: 600;
  line-height: 1.6;
  cursor: pointer;
  list-style: none;
}

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

.faq-item summary::after {
  content: "";
  position: absolute;
  right: 18px;
  top: 50%;
  width: 9px;
  height: 9px;
  margin-top: -7px;
  border-right: 2px solid var(--brand);
  border-bottom: 2px solid var(--brand);
  transform: rotate(45deg);
  transition: transform 0.2s ease;
}

.faq-item[open] summary::after {
  transform: rotate(-135deg);
  margin-top: -2px;
}

.faq-item summary:hover,
.faq-item summary:focus-visible {
  color: var(--accent);
}

.faq-answer {
  padding: 14px 18px 16px;
  border-top: 1px solid var(--line-soft);
}

.faq-answer p {
  margin: 0 0 10px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.75;
}

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

/* 提问前准备清单 */
.prep-items {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  margin-top: 22px;
}

.prep-item {
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.prep-item h3 {
  margin: 0 0 8px;
  font-size: 16px;
}

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

/* ---------------------------------------------------------
   components · 下一步入口
   --------------------------------------------------------- */

.next-step {
  padding: 26px 0 8px;
  border-top: 1px solid var(--line);
}

.next-step h2 {
  margin: 0;
}

.next-step > p {
  margin: 10px 0 0;
  max-width: 66ch;
  color: var(--ink-soft);
  font-size: 15px;
}

.next-links,
.next-step-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 26px;
  margin-top: 16px;
}

.next-links a,
.next-step-links a {
  color: var(--brand);
  font-size: 14px;
  border-bottom: 1px solid var(--line);
  padding-bottom: 1px;
}

.next-links a:hover,
.next-links a:focus-visible,
.next-step-links a:hover,
.next-step-links a:focus-visible {
  color: var(--accent);
  border-bottom-color: var(--accent);
  font-weight: 600;
}

/* ---------------------------------------------------------
   pages · 首页
   --------------------------------------------------------- */

.home-main {
  padding-bottom: 56px;
}

.home-main section {
  padding: 40px 0;
}

.home-main section + section {
  border-top: 1px solid var(--line);
}

.hero {
  padding: 44px 0 40px;
}

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 44px;
  align-items: start;
}

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

.hero-eyebrow {
  margin: 0 0 12px;
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.06em;
}

.hero-copy h1 {
  font-size: 40px;
  font-weight: 600;
  line-height: 1.25;
  color: var(--ink);
}

.hero-lead {
  margin: 16px 0 0;
  max-width: 44ch;
  color: var(--ink-soft);
  font-size: 16px;
  line-height: 1.75;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

.hero-note {
  margin: 18px 0 0;
  max-width: 46ch;
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.65;
}

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

.hero-media img {
  aspect-ratio: 4 / 3;
}

.content-media-primary {
  margin-top: 34px;
}

.content-media-primary img {
  aspect-ratio: 16 / 7;
}

/* 三条浏览路径 */
.path-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin-top: 22px;
}

.path-item {
  display: flex;
  flex-direction: column;
  padding: 20px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.path-item h3 {
  margin: 0 0 10px;
  font-size: 17px;
}

.path-item p {
  margin: 0 0 16px;
  color: var(--ink-soft);
  font-size: 14px;
}

.path-item .text-link {
  margin-top: auto;
  align-self: flex-start;
}

/* 首页各 section 标题区 */
.home-main .section-title {
  margin: 0;
}

.home-main .section-intro {
  margin: 10px 0 0;
}

/* ---------------------------------------------------------
   pages · 404
   --------------------------------------------------------- */

.error-main {
  padding: 60px 24px 72px;
}

.error-panel {
  max-width: 720px;
  margin: 0 auto;
  padding: 32px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.error-code {
  margin: 0;
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.08em;
}

.error-panel h1 {
  margin: 10px 0 0;
  font-size: 30px;
}

.error-desc {
  margin: 14px 0 0;
  color: var(--ink-soft);
  font-size: 15px;
}

.error-home-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  margin-top: 20px;
  padding: 10px 22px;
  background: var(--brand-deep);
  color: #fff;
  border-radius: 6px;
  font-size: 15px;
  font-weight: 600;
}

.error-home-link:hover,
.error-home-link:focus-visible {
  background: var(--brand);
  color: #fff;
}

.error-links {
  margin-top: 26px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}

.error-links ul {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 24px;
}

.error-links a {
  color: var(--brand);
  font-size: 14px;
  border-bottom: 1px solid var(--line);
}

.error-links a:hover,
.error-links a:focus-visible {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* ---------------------------------------------------------
   pages · 内页通用间距
   --------------------------------------------------------- */

.inner-main > section,
.page-layout .inner-main > section {
  margin-bottom: 40px;
}

.inner-main > section:last-child,
.page-layout .inner-main > section:last-child {
  margin-bottom: 0;
}

.page-layout > .breadcrumb + .inner-main,
.page-layout .inner-main {
  min-width: 0;
}

/* 服务矩阵页：对照表与图示 */
.service-index,
.service-compare,
.include-exclude,
.service-diagram {
  margin-bottom: 40px;
}

.service-index h2,
.service-compare h2,
.include-exclude h2,
.service-diagram h2 {
  margin: 0;
}

.service-index > p,
.service-compare > p,
.include-exclude > p,
.service-diagram > p {
  margin: 10px 0 0;
  max-width: 66ch;
  color: var(--ink-soft);
}

/* 观察方法页 */
.method-steps,
.filter-dimensions,
.avoid-topics,
.brief-structure {
  margin-bottom: 40px;
}

/* 合作流程页 */
.process-overview,
.timeline,
.material-checklist,
.pre-start {
  margin-bottom: 40px;
}

.inner-main:not(.page-layout .inner-main) {
  min-width: 0;
}

/* ---------------------------------------------------------
   responsive · 1080px
   --------------------------------------------------------- */

@media (max-width: 1080px) {
  .page-layout.layout-shell,
  .sidebar-left .page-layout,
  .page-layout.sidebar-left {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
  }

  .page-layout.layout-shell .inner-main,
  .sidebar-left .page-layout .inner-main,
  .page-layout.sidebar-left .inner-main {
    max-width: none;
    order: 1;
  }

  .page-layout.layout-shell .layout-aside,
  .page-layout.layout-shell .sidebar,
  .sidebar-left .page-layout .sidebar,
  .page-layout.sidebar-left .sidebar {
    order: 2;
  }

  /* 侧栏转为横向索引条 */
  .sidebar,
  .layout-aside {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }

  .anchor-nav ul,
  .related-nav ul {
    grid-auto-flow: column;
    grid-auto-columns: max-content;
    gap: 0 18px;
    overflow-x: auto;
    padding-bottom: 4px;
  }

  .anchor-nav a,
  .related-nav a {
    padding: 8px 0;
    border-bottom: 0;
    white-space: nowrap;
  }

  .process-row,
  .step-bar {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .reason-list,
  .boundary-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ---------------------------------------------------------
   responsive · 720px
   --------------------------------------------------------- */

@media (max-width: 720px) {
  .header-inner {
    min-height: 60px;
    padding: 0 16px;
    gap: 12px;
  }

  .site-header.is-tight .header-inner {
    min-height: 56px;
  }

  .brand-name {
    font-size: 18px;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    display: block;
    background: var(--surface);
    border-bottom: 1px solid var(--line);
    box-shadow: 0 12px 22px rgba(23, 32, 43, 0.1);
  }

  .site-nav ul {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 6px 16px 12px;
  }

  .site-nav ul.is-open {
    display: flex;
  }

  .site-nav a {
    min-height: 44px;
    display: flex;
    align-items: center;
    padding: 10px 4px;
    border-bottom: 1px solid var(--line-soft);
  }

  .site-nav a.is-current {
    border-bottom-color: var(--brand);
  }

  .section-inner,
  .inner-main,
  .page-layout {
    padding-left: 16px;
    padding-right: 16px;
  }

  .page-layout {
    padding-bottom: 40px;
  }

  .inner-main {
    padding-bottom: 40px;
  }

  .page-title,
  .error-panel h1 {
    font-size: 24px;
  }

  .hero-copy h1 {
    font-size: 28px;
  }

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

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

  .hero {
    padding: 28px 0 24px;
  }

  .hero-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
  }

  .hero-media {
    order: 2;
  }

  .hero-actions {
    gap: 10px;
  }

  .btn {
    flex: 1 1 auto;
  }

  .home-main section {
    padding: 28px 0;
  }

  .path-grid,
  .faq-grid,
  .category-grid,
  .prep-items,
  .field-list,
  .boundary-cols,
  .boundary-columns,
  .checklist-columns,
  .step-row,
  .step-list,
  .reason-list,
  .boundary-list,
  .revision-steps {
    grid-template-columns: minmax(0, 1fr);
  }

  .process-row,
  .step-bar {
    grid-template-columns: minmax(0, 1fr);
  }

  .step-list .step-item {
    grid-template-columns: 36px minmax(0, 1fr);
  }

  /* 表格转字段卡片 */
  .table-wrap {
    overflow-x: visible;
  }

  .data-table,
  .compare-table,
  .spec-table {
    min-width: 0;
    border: 0;
    background: transparent;
  }

  .data-table thead,
  .compare-table thead,
  .spec-table thead {
    display: none;
  }

  .data-table tbody,
  .compare-table tbody,
  .spec-table tbody {
    display: grid;
    gap: 14px;
  }

  .data-table tr,
  .compare-table tr,
  .spec-table tr {
    display: block;
    padding: 14px 16px;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: 6px;
  }

  .data-table td,
  .compare-table td,
  .spec-table td {
    display: block;
    padding: 0 0 10px;
    border-bottom: 1px solid var(--line-soft);
    font-size: 14px;
  }

  .data-table td:last-child,
  .compare-table td:last-child,
  .spec-table td:last-child {
    padding-bottom: 0;
    border-bottom: 0;
  }

  .data-table td:first-child,
  .compare-table td:first-child,
  .spec-table td:first-child {
    padding-bottom: 10px;
    color: var(--brand);
    font-size: 16px;
  }

  .index-list a {
    grid-template-columns: 36px minmax(0, 1fr);
    gap: 4px 12px;
  }

  .index-list .index-desc {
    grid-column: 2 / -1;
  }

  .timeline-node {
    grid-template-columns: minmax(0, 1fr);
    gap: 4px;
  }

  .deliverable-meta {
    grid-template-columns: minmax(0, 1fr);
    gap: 2px;
  }

  .deliverable-meta dt {
    margin-top: 8px;
  }

  .deliverable-meta dt:first-of-type {
    margin-top: 0;
  }

  .sidebar,
  .layout-aside {
    grid-template-columns: minmax(0, 1fr);
  }

  .anchor-nav ul,
  .related-nav ul {
    grid-auto-flow: row;
    grid-auto-columns: auto;
    overflow-x: visible;
  }

  .anchor-nav a,
  .related-nav a {
    padding: 10px 0;
    border-bottom: 1px solid var(--line-soft);
  }

  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 14px;
    padding: 20px 16px;
  }

  .footer-nav ul {
    gap: 4px 18px;
  }

  .footer-nav a {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
  }

  .footer-note {
    flex: 1 1 auto;
  }

  .footer-copy {
    padding: 0 16px 18px;
  }

  .error-main {
    padding: 40px 16px 56px;
  }

  .error-panel {
    padding: 22px;
  }

  .error-links ul {
    flex-direction: column;
    gap: 0;
  }

  .error-links a {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
  }

  .next-links,
  .next-step-links {
    flex-direction: column;
    gap: 0;
  }

  .next-links a,
  .next-step-links a {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
    border-bottom: 1px solid var(--line-soft);
  }

  .section-next {
    flex-direction: column;
    gap: 0;
  }

  .section-next a {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
  }

  .faq-item summary {
    padding: 14px 40px 14px 16px;
  }
}

/* ---------------------------------------------------------
   responsive · 390px
   --------------------------------------------------------- */

@media (max-width: 420px) {
  .hero-copy h1 {
    font-size: 25px;
  }

  .page-title,
  .error-panel h1 {
    font-size: 22px;
  }

  .section-title,
  .home-main .section-title {
    font-size: 19px;
  }

  .step-list .step-item {
    grid-template-columns: minmax(0, 1fr);
  }

  .step-list .step-num {
    grid-row: auto;
  }

  .index-list a {
    grid-template-columns: minmax(0, 1fr);
  }

  .index-list .index-desc {
    grid-column: auto;
  }
}

/* ---------------------------------------------------------
   动效增强（不依赖 JS 显示内容）
   --------------------------------------------------------- */

@media (prefers-reduced-motion: no-preference) {
  .path-item,
  .faq-cat,
  .category-item,
  .step-row .step-item,
  .process-row .process-item,
  .step-bar .step-item,
  .step-list .step-item,
  .reason-item,
  .boundary-item,
  .field-item,
  .prep-item,
  .rule-item,
  .revision-rule .revision-step,
  .deliverable-item {
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
  }

  .path-item:hover,
  .faq-cat:hover,
  .category-item:hover,
  .step-row .step-item:hover,
  .process-row .process-item:hover,
  .step-bar .step-item:hover,
  .step-list .step-item:hover,
  .reason-item:hover,
  .boundary-item:hover,
  .field-item:hover,
  .prep-item:hover,
  .rule-item:hover,
  .revision-rule .revision-step:hover,
  .deliverable-item:hover {
    border-color: var(--brand);
    box-shadow: 0 6px 16px rgba(23, 32, 43, 0.06);
  }

  .is-revealed {
    animation: reveal-up 0.5s ease both;
  }
}

@keyframes reveal-up {
  from {
    transform: translateY(12px);
  }
  to {
    transform: translateY(0);
  }
}

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

  .is-revealed {
    animation: none;
  }
}