/* =========================================================
   免费吃瓜 · 企业话题内容策划服务官网
   全站样式表（单文件）
   分组：base / layout / components / pages / responsive
   ========================================================= */

/* ---------------------------------------------------------
   1. base — 变量、重置、排版基础
   --------------------------------------------------------- */
:root {
  --ink: #14120F;
  --paper: #F5F1E8;
  --white: #FFFFFF;
  --brick: #E8442A;
  --signal: #FFC300;
  --hemp: #8A8378;

  --border-w: 2px;
  --shadow-x: 4px;
  --shadow-y: 4px;

  --radius-sm: 4px;
  --radius-xs: 3px;

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

  --shell-max: 1180px;
  --pad-x: 32px;
  --gap-block: 64px;

  --header-h: 64px;
  --side-w: 132px;
}

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

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

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  font-weight: 400;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4 {
  margin: 0;
  font-weight: 800;
  line-height: 1.25;
  color: var(--ink);
}

p {
  margin: 0;
}

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

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

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

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

figure {
  margin: 0;
}

button {
  font: inherit;
  color: inherit;
}

dl,
dt,
dd {
  margin: 0;
}

:focus-visible {
  outline: 3px solid var(--brick);
  outline-offset: 2px;
}

/* 通用标签 */
.tag {
  display: inline-flex;
  align-items: center;
  padding: 3px 10px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--white);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  line-height: 1.6;
  white-space: nowrap;
}

.tag-yellow {
  background: var(--signal);
}

.tag-signal {
  background: var(--signal);
}

.info-tag {
  display: inline-flex;
  align-items: center;
  padding: 3px 10px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--white);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  white-space: nowrap;
}

/* 跳转链接：默认移出视口，聚焦时回到视口内 */
.skip-link {
  position: absolute;
  top: -100px;
  left: 8px;
  z-index: 200;
  padding: 8px 14px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--signal);
  font-family: var(--font-mono);
  font-size: 13px;
}

.skip-link:focus {
  top: 8px;
}

/* ---------------------------------------------------------
   2. layout — 页头、侧栏外壳、主内容、页脚
   --------------------------------------------------------- */

/* 2.1 页头（全站统一） */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  height: var(--header-h);
  background: var(--paper);
  border-bottom: var(--border-w) solid var(--ink);
}

.header-inner {
  display: flex;
  align-items: center;
  gap: 20px;
  height: 100%;
  max-width: var(--shell-max);
  margin: 0 auto;
  padding: 0 var(--pad-x);
}

.brand {
  display: inline-flex;
  align-items: center;
  flex: 0 0 auto;
  padding: 4px 10px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--ink);
}

.brand-name {
  font-size: 16px;
  font-weight: 800;
  color: var(--paper);
  white-space: nowrap;
}

.brand:hover .brand-name {
  color: var(--signal);
}

.header-tagline {
  flex: 1 1 auto;
  min-width: 0;
  font-size: 13px;
  color: var(--hemp);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
}

.header-link {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  padding: 0 14px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--brick);
  color: var(--ink);
  font-size: 14px;
  font-weight: 700;
  white-space: nowrap;
}

.header-link:hover {
  color: var(--ink);
  box-shadow: var(--shadow-x) var(--shadow-y) 0 var(--ink);
}

.header-link.is-current {
  background: var(--ink);
  color: var(--paper);
}

.header-link.is-current:hover {
  color: var(--signal);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
  width: 44px;
  height: 44px;
  padding: 0 10px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--white);
  cursor: pointer;
}

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

/* 2.2 侧栏 + 主内容外壳 */
.layout-shell {
  display: grid;
  grid-template-columns: var(--side-w) minmax(0, 1fr);
  align-items: start;
  max-width: var(--shell-max);
  margin: 0 auto;
  padding: 0 var(--pad-x);
  gap: 0 32px;
}

.side-nav {
  position: sticky;
  top: var(--header-h);
  align-self: start;
  padding: 24px 0;
}

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

.side-nav-item,
.side-nav-link,
.side-item {
  display: flex;
  align-items: center;
  gap: 8px;
  min-height: 44px;
  padding: 6px 8px;
  border: var(--border-w) solid transparent;
  border-radius: var(--radius-xs);
  font-size: 14px;
  font-weight: 600;
  color: var(--ink);
}

.side-nav-item:hover,
.side-nav-link:hover,
.side-item:hover {
  border-color: var(--ink);
  background: var(--white);
  color: var(--ink);
}

.side-nav-item.is-current,
.side-nav-link.is-current,
.side-item.is-current {
  background: var(--brick);
  border-color: var(--ink);
  color: var(--ink);
}

.side-nav-icon,
.side-icon {
  flex: 0 0 auto;
  width: 20px;
  height: 20px;
}

.side-nav-text,
.side-label {
  display: block;
  line-height: 1.4;
}

.site-main {
  min-width: 0;
  padding: 32px 0 56px;
}

/* 移动端抽屉：默认隐藏，靠 hidden 属性控制 */
.drawer-backdrop,
.mobile-drawer {
  display: none;
}

.drawer-nav,
.drawer-list {
  display: block;
}

.drawer-item,
.drawer-link {
  display: flex;
  align-items: center;
  min-height: 48px;
  padding: 8px 12px;
  border-bottom: var(--border-w) solid var(--ink);
  font-size: 15px;
  font-weight: 600;
}

.drawer-item.is-current,
.drawer-link.is-current {
  background: var(--brick);
}

/* 2.3 内页骨架：面包屑、页面标题区、内容容器 */
.inner-main {
  max-width: var(--shell-max);
  margin: 0 auto;
  padding: 28px var(--pad-x) 56px;
}

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 20px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--hemp);
}

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

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

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

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

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

.page-title {
  font-size: 38px;
  font-weight: 800;
  line-height: 1.2;
  color: var(--ink);
}

.page-title-desc,
.page-intro {
  max-width: 760px;
  margin-top: 12px;
  font-size: 16px;
  color: var(--ink);
}

.page-title-tags,
.page-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 16px;
}

.page-title {
  margin-bottom: 0;
}

section.page-title {
  margin-bottom: var(--gap-block);
}

/* 2.4 页脚（全站统一） */
.site-footer {
  background: var(--ink);
  color: var(--paper);
  border-top: var(--border-w) solid var(--ink);
}

.footer-inner {
  max-width: var(--shell-max);
  margin: 0 auto;
  padding: 48px var(--pad-x) 28px;
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 32px;
}

.footer-title {
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--signal);
}

.footer-links li + li {
  margin-top: 8px;
}

.footer-links a {
  display: inline-block;
  min-height: 24px;
  font-size: 14px;
  color: var(--paper);
}

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

.footer-brand {
  margin-top: 40px;
  padding-top: 20px;
  border-top: 1px solid var(--hemp);
}

.footer-brand-name {
  font-size: 18px;
  font-weight: 800;
  color: var(--paper);
}

.footer-brand-desc {
  margin-top: 6px;
  max-width: 720px;
  font-size: 14px;
  color: var(--hemp);
}

.footer-copy {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--hemp);
}

/* ---------------------------------------------------------
   3. components — 通用区块、卡片、列表、步骤、FAQ
   --------------------------------------------------------- */

/* 3.1 区块标题 */
.section-head {
  margin-bottom: 24px;
}

.section-head h2 {
  font-size: 26px;
}

.section-head p {
  margin-top: 10px;
  max-width: 760px;
  font-size: 15px;
  color: var(--ink);
}

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

.section-desc,
.section-intro,
.section-lead {
  margin-top: 10px;
  max-width: 780px;
  font-size: 15px;
  color: var(--ink);
}

.section-more {
  margin-top: 20px;
}

.link-more {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 16px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--white);
  font-size: 14px;
  font-weight: 700;
}

.link-more:hover {
  background: var(--signal);
  color: var(--ink);
  box-shadow: var(--shadow-x) var(--shadow-y) 0 var(--ink);
}

/* 3.2 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 20px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  font-size: 15px;
  font-weight: 700;
}

.btn-primary {
  background: var(--brick);
  color: var(--ink);
}

.btn-primary:hover {
  color: var(--ink);
  box-shadow: var(--shadow-x) var(--shadow-y) 0 var(--ink);
}

.btn-ghost {
  background: var(--white);
  color: var(--ink);
}

.btn-ghost:hover {
  color: var(--ink);
  box-shadow: var(--shadow-x) var(--shadow-y) 0 var(--ink);
}

/* 3.3 图片容器统一约束 */
.hero-figure,
.archive-figure,
.page-figure,
.method-figure,
.service-detail-media,
.coop-figure,
.section-media,
.section-figure {
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
  overflow: hidden;
}

.hero-figure img,
.archive-figure img,
.page-figure img,
.method-figure img,
.service-detail-media img,
.coop-figure img,
.section-media img,
.section-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 10;
  object-fit: cover;
}

.hero-figure figcaption,
.archive-figure figcaption,
.page-figure figcaption,
.figure-caption,
.media-caption,
.coop-figure figcaption,
.section-media figcaption,
.section-figure figcaption {
  padding: 10px 14px;
  border-top: var(--border-w) solid var(--ink);
  background: var(--white);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--hemp);
}

/* 3.4 折叠问答（首页摘要与 FAQ 页共用结构） */
.faq-list {
  display: grid;
  gap: 12px;
}

.faq-item {
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.faq-item + .faq-item {
  margin-top: 12px;
}

.faq-q,
.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-height: 52px;
  padding: 12px 16px;
  font-size: 16px;
  font-weight: 700;
  cursor: pointer;
  list-style: none;
}

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

.faq-q::after,
.faq-question::after {
  content: "+";
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 20px;
  line-height: 1;
  color: var(--brick);
}

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

.faq-a,
.faq-answer {
  padding: 0 16px 16px;
  border-top: 1px solid var(--hemp);
}

.faq-a p,
.faq-answer p {
  margin-top: 12px;
  font-size: 15px;
}

/* 3.5 相关入口块 */
.related-links {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
}

.related-links-label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--hemp);
}

.related-links-item {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  padding: 0 14px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--white);
  font-size: 14px;
}

.related-links-item:hover {
  background: var(--signal);
  color: var(--ink);
}

/* ---------------------------------------------------------
   4. pages — 首页与各内页专属模块
   --------------------------------------------------------- */

/* 4.1 首页 */
.home-main {
  padding-top: 32px;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
  gap: 40px;
  align-items: start;
  padding-bottom: var(--gap-block);
  border-bottom: var(--border-w) solid var(--ink);
}

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

.hero-kicker {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--hemp);
}

.hero-copy h1 {
  margin-top: 14px;
  font-size: 38px;
}

.hero-lead {
  margin-top: 16px;
  max-width: 560px;
  font-size: 16px;
}

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

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 24px;
}

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

.services,
.archive,
.method,
.cooperation,
.faq,
.entry {
  padding: var(--gap-block) 0 0;
}

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

.service-card {
  padding: 20px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.service-card:hover {
  box-shadow: var(--shadow-x) var(--shadow-y) 0 var(--ink);
}

.card-index {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--hemp);
}

.card-title {
  margin-top: 8px;
  font-size: 18px;
}

.card-desc {
  margin-top: 10px;
  font-size: 15px;
}

.card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 16px;
}

/* 首页项目档案预览 */
.category-tags {
  margin-bottom: 20px;
}

.category-tags .tag-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.category-tags > .tag-link {
  margin: 0 8px 8px 0;
}

.tag-link {
  display: inline-flex;
  align-items: center;
  min-height: 38px;
  padding: 0 14px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--signal);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
}

.tag-link:hover {
  background: var(--brick);
  color: var(--ink);
}

.archive-body {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
  gap: 28px;
  align-items: start;
}

.row-list {
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
  overflow: hidden;
}

.row {
  display: grid;
  grid-template-columns: 1.1fr 1.6fr 1.6fr 1.1fr;
  border-top: 1px solid var(--hemp);
}

.row:first-child {
  border-top: 0;
}

.row-head {
  background: var(--ink);
}

.row-head .cell {
  color: var(--paper);
}

.cell {
  min-width: 0;
  padding: 12px 14px;
  font-size: 14px;
  border-left: 1px solid var(--hemp);
  overflow-wrap: break-word;
}

.cell:first-child {
  border-left: 0;
}

.cell-head {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.cell-key {
  font-weight: 700;
}

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

/* 首页策划方法条 */
.method-steps {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.method-step {
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.step-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 28px;
  height: 28px;
  padding: 0 8px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--brick);
  font-family: var(--font-mono);
  font-size: 12px;
}

.method-step .step-name {
  margin-top: 12px;
  font-size: 18px;
}

.step-desc {
  margin-top: 8px;
  font-size: 14px;
}

/* 首页合作流程 */
.coop-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.coop-step {
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-left-width: 6px;
  border-radius: var(--radius-sm);
  background: var(--white);
}

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

.coop-own,
.coop-you,
.coop-confirm {
  margin-top: 10px;
  font-size: 14px;
}

.coop-own::before,
.coop-you::before,
.coop-confirm::before {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--hemp);
  margin-right: 6px;
}

.coop-own::before {
  content: "我方";
}

.coop-you::before {
  content: "客户";
}

.coop-confirm::before {
  content: "确认";
}

/* 首页合作入口 */
.entry {
  padding-bottom: 0;
}

.entry h2 {
  font-size: 26px;
}

.entry > p {
  margin-top: 10px;
  max-width: 780px;
  font-size: 15px;
}

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

.entry-card {
  display: block;
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.entry-card:hover {
  background: var(--signal);
  color: var(--ink);
  box-shadow: var(--shadow-x) var(--shadow-y) 0 var(--ink);
}

.entry-name {
  display: block;
  font-size: 17px;
  font-weight: 800;
}

.entry-desc {
  display: block;
  margin-top: 8px;
  font-size: 14px;
}

.related-links[aria-label="相关内容"] {
  margin-top: 40px;
  padding-top: 20px;
  border-top: var(--border-w) solid var(--ink);
}

/* 4.2 服务能力页 */
.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 288px;
  gap: 40px;
  align-items: start;
}

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

.service-overview {
  margin-bottom: var(--gap-block);
}

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

.overview-card {
  padding: 20px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.overview-num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--hemp);
}

.overview-name {
  margin-top: 8px;
  font-size: 18px;
}

.overview-desc {
  margin-top: 10px;
  font-size: 15px;
}

.service-detail {
  margin-bottom: var(--gap-block);
}

.service-detail-head {
  padding-bottom: 16px;
  border-bottom: var(--border-w) solid var(--ink);
}

.service-detail-num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--hemp);
}

.service-detail-title {
  margin-top: 8px;
  font-size: 26px;
}

.service-detail-lead {
  margin-top: 10px;
  max-width: 780px;
  font-size: 15px;
}

.service-detail-media {
  margin-top: 20px;
}

.service-detail-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  margin-top: 24px;
}

.detail-block {
  min-width: 0;
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.detail-block-title {
  font-size: 18px;
}

.detail-list {
  margin-top: 12px;
}

.detail-list li {
  position: relative;
  padding-left: 18px;
  margin-top: 8px;
  font-size: 15px;
}

.detail-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 8px;
  height: 8px;
  background: var(--brick);
  border: 1px solid var(--ink);
}

.service-boundary {
  margin-bottom: var(--gap-block);
}

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

.boundary-block {
  min-width: 0;
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.boundary-title {
  font-size: 18px;
}

.boundary-list {
  margin-top: 12px;
}

.boundary-list li {
  position: relative;
  padding-left: 18px;
  margin-top: 8px;
  font-size: 15px;
}

.boundary-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 8px;
  height: 8px;
  background: var(--signal);
  border: 1px solid var(--ink);
}

.related {
  min-width: 0;
}

.related-group + .related-group {
  margin-top: 28px;
}

.related-title {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink);
  padding-bottom: 10px;
  border-bottom: var(--border-w) solid var(--ink);
}

.related-list {
  margin-top: 12px;
}

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

.related-list a {
  display: block;
  min-height: 40px;
  padding: 8px 12px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--white);
  font-size: 14px;
}

.related-list a:hover {
  background: var(--signal);
  color: var(--ink);
}

/* 4.3 项目档案页 */
.page-figure {
  margin-bottom: var(--gap-block);
}

.category-tags .tag-bar {
  margin-top: 16px;
}

.project-rows {
  margin-bottom: var(--gap-block);
}

.project-row {
  padding: 20px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.project-row + .project-row {
  margin-top: 18px;
}

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

.project-fields {
  display: grid;
  grid-template-columns: 140px minmax(0, 1fr);
  gap: 0;
  margin-top: 14px;
  border-top: 1px solid var(--hemp);
}

.field-label {
  padding: 10px 0;
  border-bottom: 1px solid var(--hemp);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--hemp);
}

.field-value {
  padding: 10px 0;
  border-bottom: 1px solid var(--hemp);
  font-size: 15px;
}

.module-map {
  margin-bottom: var(--gap-block);
}

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

.map-col {
  min-width: 0;
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.map-col-title {
  font-size: 18px;
}

.map-list {
  margin-top: 12px;
}

.map-list li {
  position: relative;
  padding-left: 18px;
  margin-top: 8px;
  font-size: 15px;
}

.map-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 8px;
  height: 8px;
  background: var(--brick);
  border: 1px solid var(--ink);
}

.archive-entry {
  margin-bottom: var(--gap-block);
}

.entry-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
  margin-top: 20px;
}

.entry-grid .entry-card {
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.entry-grid .entry-name {
  font-size: 17px;
}

.entry-grid .entry-name a {
  display: inline-block;
  min-height: 28px;
}

.entry-grid .entry-desc {
  margin-top: 8px;
  font-size: 14px;
}

/* 4.4 策划方法页 */
.method-index {
  margin-bottom: 40px;
}

.method-index-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.method-index-link {
  display: inline-flex;
  align-items: center;
  min-height: 42px;
  padding: 0 14px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--white);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
}

.method-index-link:hover {
  background: var(--signal);
  color: var(--ink);
}

.method-figure {
  margin-bottom: var(--gap-block);
}

.method-section {
  margin-bottom: var(--gap-block);
}

.method-section h2 {
  font-size: 26px;
}

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

.judgement-col {
  min-width: 0;
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.col-title {
  font-size: 18px;
}

.col-desc {
  margin-top: 10px;
  font-size: 15px;
}

.check-list {
  margin-top: 12px;
}

.check-item {
  position: relative;
  padding-left: 26px;
  margin-top: 10px;
  font-size: 15px;
}

.check-item::before {
  content: "✓";
  position: absolute;
  left: 0;
  top: 0;
  width: 18px;
  height: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--signal);
  font-size: 12px;
  line-height: 1;
}

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

.structure-col {
  min-width: 0;
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.plain-list {
  margin-top: 12px;
}

.plain-list li {
  position: relative;
  padding-left: 18px;
  margin-top: 8px;
  font-size: 15px;
}

.plain-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 8px;
  height: 8px;
  background: var(--brick);
  border: 1px solid var(--ink);
}

.level-list {
  margin-top: 20px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
  overflow: hidden;
}

.level-item {
  display: grid;
  grid-template-columns: 64px minmax(0, 1fr);
  align-items: start;
  gap: 16px;
  padding: 16px 18px;
  border-top: 1px solid var(--hemp);
}

.level-item:first-child {
  border-top: 0;
}

.level-no {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 40px;
  height: 28px;
  padding: 0 8px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--brick);
  font-family: var(--font-mono);
  font-size: 12px;
}

.level-desc {
  min-width: 0;
  font-size: 15px;
}

.review-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  margin-top: 20px;
}

.review-item {
  min-width: 0;
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.review-title {
  font-size: 18px;
}

.review-desc {
  margin-top: 10px;
  font-size: 15px;
}

.related .related-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  margin-top: 20px;
}

.related .related-list li + li {
  margin-top: 0;
}

/* 4.5 合作方式页 */
.coop-steps,
.coop-preparation,
.coop-boundary,
.coop-related {
  margin-bottom: var(--gap-block);
}

.step-item {
  padding: 20px;
  border: var(--border-w) solid var(--ink);
  border-left-width: 6px;
  border-radius: var(--radius-sm);
  background: var(--white);
}

.step-item + .step-item {
  margin-top: 18px;
}

.step-num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--hemp);
}

.step-item .step-name {
  margin-top: 8px;
  font-size: 20px;
}

.step-fields {
  display: grid;
  grid-template-columns: 120px minmax(0, 1fr);
  margin-top: 14px;
  border-top: 1px solid var(--hemp);
}

.step-fields dt {
  padding: 10px 0;
  border-bottom: 1px solid var(--hemp);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--hemp);
}

.step-fields dd {
  padding: 10px 0;
  border-bottom: 1px solid var(--hemp);
  font-size: 15px;
}

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

.prep-col {
  min-width: 0;
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.prep-title {
  font-size: 18px;
}

.prep-list {
  margin-top: 12px;
}

.prep-list li {
  position: relative;
  padding-left: 18px;
  margin-top: 8px;
  font-size: 15px;
}

.prep-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 8px;
  height: 8px;
  background: var(--signal);
  border: 1px solid var(--ink);
}

.coop-boundary .boundary-list {
  margin-top: 20px;
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

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

.related-card {
  display: block;
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.related-card:hover {
  background: var(--signal);
  color: var(--ink);
  box-shadow: var(--shadow-x) var(--shadow-y) 0 var(--ink);
}

.related-card-title {
  font-size: 17px;
}

.related-card-desc {
  margin-top: 8px;
  font-size: 14px;
}

.coop-figure {
  margin-bottom: 0;
}

/* 4.6 常见问题页 */
.faq-group {
  margin-bottom: var(--gap-block);
}

.faq-group .section-media {
  margin: 20px 0 24px;
}

.related-entry {
  margin-bottom: var(--gap-block);
}

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

.related-entry .related-links li {
  min-width: 0;
}

.related-entry .related-links a {
  display: block;
  min-height: 44px;
  padding: 12px 16px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
  font-size: 15px;
  font-weight: 700;
}

.related-entry .related-links a:hover {
  background: var(--signal);
  color: var(--ink);
  box-shadow: var(--shadow-x) var(--shadow-y) 0 var(--ink);
}

/* 4.7 关于我们页 */
.page-layout .layout-main {
  min-width: 0;
}

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

.positioning,
.principles,
.working-style,
.related {
  margin-bottom: var(--gap-block);
}

.positioning > h2,
.principles > h2,
.working-style > h2,
.related > h2,
.glossary > h2,
.scope-note > h2 {
  font-size: 26px;
}

.positioning .section-figure {
  margin: 20px 0;
}

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

.positioning-col {
  min-width: 0;
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.positioning-col h3 {
  font-size: 18px;
}

.positioning-col p {
  margin-top: 10px;
  font-size: 15px;
}

.principle-list {
  display: grid;
  gap: 16px;
  margin-top: 20px;
}

.principle-item {
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.principle-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 28px;
  height: 28px;
  padding: 0 8px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--brick);
  font-family: var(--font-mono);
  font-size: 12px;
}

.principle-item h3 {
  margin-top: 12px;
  font-size: 18px;
}

.principle-item p {
  margin-top: 8px;
  font-size: 15px;
}

.working-list {
  margin-top: 20px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
  overflow: hidden;
}

.working-item {
  padding: 16px 18px;
  border-top: 1px solid var(--hemp);
}

.working-item:first-child {
  border-top: 0;
}

.working-item h3 {
  font-size: 18px;
}

.working-item p {
  margin-top: 8px;
  font-size: 15px;
}

.section-note {
  margin-top: 18px;
  font-size: 15px;
}

.section-note a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  padding: 0 14px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--white);
  font-weight: 700;
}

.section-note a:hover {
  background: var(--signal);
  color: var(--ink);
}

.related .related-links {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  margin-top: 20px;
}

.related .related-links li {
  min-width: 0;
}

.related .related-links a {
  display: block;
  min-height: 44px;
  padding: 12px 14px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
  font-size: 14px;
  font-weight: 700;
}

.related .related-links a:hover {
  background: var(--signal);
  color: var(--ink);
}

.glossary,
.scope-note {
  min-width: 0;
  padding: 18px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
}

.scope-note {
  margin-top: 24px;
}

.glossary-list {
  margin-top: 14px;
}

.glossary-list dt {
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--ink);
}

.glossary-list dt:first-child {
  margin-top: 0;
}

.glossary-list dd {
  margin-top: 4px;
  font-size: 14px;
  color: var(--hemp);
}

.scope-note p {
  margin-top: 12px;
  font-size: 15px;
}

/* 4.8 404 页 */
.error-main {
  max-width: var(--shell-max);
  margin: 0 auto;
  padding: 64px var(--pad-x);
}

.error-panel {
  max-width: 640px;
  padding: 32px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
  box-shadow: 6px 6px 0 var(--ink);
}

.error-code {
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.12em;
  color: var(--hemp);
}

.error-panel h1 {
  margin-top: 12px;
  font-size: 38px;
}

.error-text {
  margin-top: 14px;
  font-size: 16px;
}

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

.error-links a {
  display: inline-flex;
  align-items: center;
  min-height: 42px;
  padding: 0 14px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--white);
  font-size: 14px;
}

.error-links a:hover {
  background: var(--signal);
  color: var(--ink);
}

.error-home {
  display: inline-flex;
  align-items: center;
  min-height: 46px;
  margin-top: 24px;
  padding: 0 20px;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-xs);
  background: var(--brick);
  font-weight: 700;
}

.error-home:hover {
  color: var(--ink);
  box-shadow: var(--shadow-x) var(--shadow-y) 0 var(--ink);
}

/* ---------------------------------------------------------
   5. responsive — 900px / 600px 两级断点
   --------------------------------------------------------- */
@media (max-width: 900px) {
  :root {
    --pad-x: 20px;
    --gap-block: 48px;
  }

  .header-tagline {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }

  /* 侧栏在 900px 以下收进抽屉，主内容占满 */
  .layout-shell {
    grid-template-columns: minmax(0, 1fr);
    gap: 0;
  }

  .side-nav {
    position: static;
    padding: 0;
  }

  /* 只收起列表本身，父容器保持可见 */
  .layout-shell > .side-nav .side-nav-list,
  .side-nav > .side-nav-list {
    display: none;
  }

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

  /* 抽屉形态（hidden 属性控制显隐，不用 display:none 阻断子列表） */
  .drawer-backdrop,
  .mobile-drawer {
    display: block;
    position: fixed;
    inset: var(--header-h) 0 0 0;
    z-index: 70;
    background: var(--paper);
    border-top: var(--border-w) solid var(--ink);
    overflow-y: auto;
  }

  .drawer-backdrop[hidden],
  .mobile-drawer[hidden] {
    display: none;
  }

  .drawer-item,
  .drawer-link {
    font-size: 16px;
  }

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

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

  .service-grid,
  .coop-list,
  .overview-grid,
  .service-detail-grid,
  .boundary-grid,
  .judgement-grid,
  .prep-cols,
  .positioning-cols,
  .review-list,
  .map-columns {
    grid-template-columns: minmax(0, 1fr);
  }

  .method-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .archive-body {
    grid-template-columns: minmax(0, 1fr);
  }

  .entry-links,
  .entry-grid,
  .structure-grid,
  .related-grid,
  .related .related-list,
  .related .related-links,
  .related-entry .related-links {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-layout {
    grid-template-columns: minmax(0, 1fr);
    gap: 32px;
  }

  .page-title,
  .error-panel h1 {
    font-size: 30px;
  }

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

@media (max-width: 600px) {
  :root {
    --gap-block: 40px;
  }

  body {
    font-size: 15px;
  }

  .header-inner {
    gap: 12px;
  }

  .brand {
    padding: 4px 8px;
  }

  .brand-name {
    font-size: 15px;
  }

  .header-link {
    min-height: 38px;
    padding: 0 10px;
    font-size: 13px;
  }

  .page-title,
  .error-panel h1 {
    font-size: 28px;
  }

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

  .section-head h2,
  .section-title,
  .service-detail-title,
  .method-section h2,
  .positioning > h2,
  .principles > h2,
  .working-style > h2,
  .related > h2,
  .glossary > h2,
  .scope-note > h2,
  .entry h2 {
    font-size: 22px;
  }

  .method-steps {
    grid-template-columns: minmax(0, 1fr);
  }

  .entry-links,
  .entry-grid,
  .structure-grid,
  .related-grid,
  .related .related-list,
  .related .related-links,
  .related-entry .related-links {
    grid-template-columns: minmax(0, 1fr);
  }

  /* 表格行改为字段名 + 字段值上下堆叠 */
  .row,
  .row-head {
    grid-template-columns: minmax(0, 1fr);
  }

  .row-head {
    display: none;
  }

  .cell {
    border-left: 0;
    border-top: 1px solid var(--hemp);
  }

  .cell:first-child {
    border-top: 0;
  }

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

  .field-label,
  .step-fields dt {
    padding-bottom: 0;
    border-bottom: 0;
  }

  .field-value,
  .step-fields dd {
    padding-top: 2px;
  }

  .level-item {
    grid-template-columns: minmax(0, 1fr);
    gap: 10px;
  }

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

  .error-panel {
    padding: 24px 20px;
    box-shadow: 4px 4px 0 var(--ink);
  }

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

  .error-links a {
    justify-content: center;
  }
}

/* 尊重减少动效偏好 */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}

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

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