/* ==========================================================================
   吃瓜群 · 全站样式
   分组：base / layout / components / pages / responsive
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. base — 变量、重置、排版、通用元素
   -------------------------------------------------------------------------- */

:root {
  --c-ink: #1b1f24;
  --c-ink-2: #262c33;
  --c-paper: #f4f1ea;
  --c-card: #ffffff;
  --c-text: #1b1f24;
  --c-muted: #5b6470;
  --c-accent: #c8842a;
  --c-ok: #2f7d5d;
  --c-gray: #8a8f98;
  --c-line: #dcd7cc;
  --c-line-dark: #3a424b;

  --font-sans: system-ui, -apple-system, "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Source Han Sans SC", sans-serif;

  --shell: 1120px;
  --reading: 760px;
  --radius: 6px;
  --radius-sm: 4px;

  --shadow-1: 0 1px 2px rgba(27, 31, 36, 0.06);
  --shadow-2: 0 6px 18px rgba(27, 31, 36, 0.1);

  --header-h: 64px;
  --tabbar-h: 56px;
}

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

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

body {
  margin: 0;
  background: var(--c-paper);
  color: var(--c-text);
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.85;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4 {
  margin: 0;
  font-weight: 600;
  line-height: 1.3;
  color: var(--c-text);
}

h1 {
  font-size: 40px;
  line-height: 1.25;
}

h2 {
  font-size: 28px;
  line-height: 1.35;
}

h3 {
  font-size: 20px;
  line-height: 1.45;
}

h4 {
  font-size: 17px;
  line-height: 1.5;
}

p {
  margin: 0 0 14px;
}

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

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

a {
  color: inherit;
  text-decoration: none;
}

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

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

figure {
  margin: 0;
}

figcaption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.7;
  letter-spacing: 0.04em;
  color: var(--c-muted);
}

button {
  font: inherit;
  color: inherit;
}

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

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

/* --------------------------------------------------------------------------
   2. layout — 外壳、页头、导航、主区、页脚、移动底栏
   -------------------------------------------------------------------------- */

.container {
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 24px;
}

.container.narrow,
.container.reading-col {
  max-width: var(--reading);
}

.site-main {
  display: block;
  padding-bottom: 40px;
}

/* 页头 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: var(--c-ink);
  color: #f2efe9;
  border-bottom: 1px solid var(--c-line-dark);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: var(--header-h);
}

.brand {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 2px;
  padding: 8px 0;
  color: #f7f4ee;
}

.brand:hover {
  color: #ffffff;
}

.brand-name {
  font-size: 19px;
  font-weight: 600;
  line-height: 1.2;
}

.brand-slogan {
  font-size: 12px;
  line-height: 1.4;
  letter-spacing: 0.04em;
  color: #a7aeb8;
}

/* 主导航 */
.site-nav {
  display: block;
}

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

.nav-list li {
  display: block;
}

.nav-list a {
  display: block;
  padding: 10px 12px;
  font-size: 15px;
  line-height: 1.4;
  color: #d6d3cc;
  border-radius: var(--radius-sm);
  white-space: nowrap;
}

.nav-list a:hover {
  color: #ffffff;
  background: rgba(255, 255, 255, 0.07);
}

.nav-list a.is-current {
  color: #ffffff;
  background: rgba(200, 132, 42, 0.22);
  box-shadow: inset 0 -2px 0 var(--c-accent);
}

/* 汉堡按钮 */
.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 11px;
  background: transparent;
  border: 1px solid var(--c-line-dark);
  border-radius: var(--radius-sm);
  cursor: pointer;
}

.nav-toggle-bar {
  display: block;
  height: 2px;
  margin: 4px 0;
  background: #e8e4dc;
  border-radius: 1px;
}

.mobile-nav {
  background: var(--c-ink-2);
  border-top: 1px solid var(--c-line-dark);
}

.mobile-nav[hidden] {
  display: none;
}

.mobile-nav-list {
  display: flex;
  flex-direction: column;
  padding: 8px 24px 16px;
}

.mobile-nav-list a {
  display: block;
  padding: 12px 4px;
  font-size: 16px;
  color: #ddd8d0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.mobile-nav-list a.is-current {
  color: #ffffff;
  border-left: 3px solid var(--c-accent);
  padding-left: 12px;
}

/* 内页骨架 */
.inner-main {
  display: block;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 20px 24px 0;
  font-size: 13px;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: var(--c-muted);
}

.breadcrumb a {
  color: var(--c-muted);
  text-decoration: underline;
  text-underline-offset: 3px;
}

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

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

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

.page-header {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 14px 24px 0;
}

.page-title {
  font-size: 34px;
  font-weight: 600;
  line-height: 1.25;
  color: var(--c-text);
}

/* 页脚 */
.site-footer {
  margin-top: 56px;
  background: var(--c-ink);
  color: #c9c5bd;
  font-size: 15px;
  line-height: 1.75;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 32px;
  padding-top: 48px;
  padding-bottom: 36px;
}

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

.footer-brand-name {
  margin: 0 0 10px;
  font-size: 19px;
  font-weight: 600;
  color: #ffffff;
}

.footer-brand-desc {
  margin: 0;
  color: #a7aeb8;
}

.footer-col-title {
  margin: 0 0 14px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: #ffffff;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a {
  color: #c9c5bd;
}

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

.footer-note {
  margin: 0 0 14px;
  color: #a7aeb8;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding-top: 18px;
  padding-bottom: 22px;
  border-top: 1px solid var(--c-line-dark);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: #8f96a0;
}

.footer-mark {
  color: #a7aeb8;
}

.footer-bottom-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
}

.footer-bottom-nav a {
  color: #a7aeb8;
}

.footer-bottom-nav a:hover {
  color: var(--c-accent);
}

/* 移动底部固定导航 */
.mobile-bottom-nav,
.mobile-tabbar {
  display: none;
}

/* 通用分节 */
.section {
  padding: 56px 0;
}

.section-head {
  margin-bottom: 26px;
}

.section-intro,
.section-desc,
.section-note,
.section-lead {
  margin: 10px 0 0;
  color: var(--c-muted);
}

.section-more {
  margin: 24px 0 0;
}

.text-link {
  display: inline-block;
  font-size: 15px;
  color: var(--c-accent);
  border-bottom: 1px solid rgba(200, 132, 42, 0.4);
  padding-bottom: 2px;
}

.text-link:hover {
  color: var(--c-ink);
  border-bottom-color: var(--c-ink);
}

/* --------------------------------------------------------------------------
   3. components — 按钮、标签、卡片、表格、时间轴、手风琴、图片框
   -------------------------------------------------------------------------- */

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 11px 22px;
  font-size: 15px;
  font-weight: 500;
  line-height: 1.4;
  border-radius: var(--radius);
  border: 1px solid transparent;
  transition: transform 0.16s ease, background-color 0.16s ease,
    border-color 0.16s ease, color 0.16s ease;
}

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

.btn-primary:hover {
  background: #b2741f;
  color: #ffffff;
  transform: translateY(-1px);
}

.btn-ghost {
  background: transparent;
  color: #eae6de;
  border-color: rgba(234, 230, 222, 0.42);
}

.btn-ghost:hover {
  color: #ffffff;
  border-color: #ffffff;
  transform: translateY(-1px);
}

/* 状态标签 */
.tag,
.status-tag {
  display: inline-block;
  padding: 2px 9px;
  font-size: 12px;
  font-weight: 500;
  line-height: 1.7;
  letter-spacing: 0.04em;
  border-radius: 3px;
  white-space: nowrap;
}

.tag-ok,
.status-open {
  background: rgba(47, 125, 93, 0.12);
  color: var(--c-ok);
  border: 1px solid rgba(47, 125, 93, 0.3);
}

.tag-pre,
.status-conditional {
  background: rgba(138, 143, 152, 0.14);
  color: #5b6470;
  border: 1px solid rgba(138, 143, 152, 0.34);
}

.tag-eval,
.status-evaluate {
  background: rgba(200, 132, 42, 0.12);
  color: #a86c17;
  border: 1px solid rgba(200, 132, 42, 0.34);
}

/* 内容卡片通用 */
.delivery-col,
.method-point,
.summary-card,
.service-item,
.deliverable-item,
.example-card,
.pitfall-item,
.collab-item,
.principle-item,
.boundary-item,
.side-card,
.side-block,
.aside-block {
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-1);
}

/* 要点列表 */
.check-list,
.point-list,
.deliverable-points,
.acceptance-points,
.side-list,
.aside-list,
.order-list,
.summary-points,
.example-structure,
.prepare-list,
.error-link-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.check-list li,
.point-list li,
.deliverable-points li,
.acceptance-points li,
.side-list li,
.aside-list li,
.summary-points li {
  position: relative;
  padding-left: 18px;
  color: var(--c-text);
}

.check-list li::before,
.point-list li::before,
.deliverable-points li::before,
.acceptance-points li::before,
.side-list li::before,
.aside-list li::before,
.summary-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.78em;
  width: 6px;
  height: 6px;
  background: var(--c-accent);
  border-radius: 1px;
}

/* 表格 */
.table-wrap {
  width: 100%;
  overflow-x: auto;
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

.data-table,
.matrix-table {
  min-width: 620px;
  font-size: 15px;
  line-height: 1.6;
}

.data-table caption,
.matrix-table caption,
.table-caption {
  padding: 14px 16px 0;
  text-align: left;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--c-muted);
}

.data-table th,
.data-table td,
.matrix-table th,
.matrix-table td {
  padding: 13px 16px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--c-line);
}

.data-table thead th,
.matrix-table thead th {
  background: #efece4;
  font-weight: 600;
  color: var(--c-text);
  border-bottom: 1px solid #cfc9bd;
}

.matrix-table thead th {
  position: sticky;
  top: 0;
  z-index: 2;
}

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

.data-table tbody tr:hover,
.matrix-table tbody tr:hover {
  background: #faf8f3;
}

/* 时间轴（首页横向） */
.timeline {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.timeline-node {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 22px 18px;
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-top: 3px solid var(--c-accent);
  border-radius: var(--radius);
  box-shadow: var(--shadow-1);
  transition: transform 0.16s ease, border-color 0.16s ease;
}

.timeline-node:hover {
  transform: translateY(-2px);
  border-color: #c8c1b3;
}

.timeline-index {
  display: inline-block;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--c-accent);
}

.timeline-work,
.timeline-output {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--c-muted);
}

.timeline-output {
  color: var(--c-text);
}

/* FAQ 手风琴 */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq-item {
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-1);
  transition: border-color 0.16s ease;
}

.faq-item:hover {
  border-color: #c8c1b3;
}

.faq-item summary,
.faq-question {
  position: relative;
  display: block;
  padding: 16px 46px 16px 18px;
  font-size: 17px;
  font-weight: 500;
  line-height: 1.6;
  color: var(--c-text);
  cursor: pointer;
  list-style: none;
}

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

.faq-item summary::after,
.faq-question::after {
  content: "+";
  position: absolute;
  right: 18px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 20px;
  line-height: 1;
  color: var(--c-accent);
}

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

.faq-answer {
  padding: 0 18px 18px;
  border-top: 1px solid var(--c-line);
  margin-top: 0;
  padding-top: 14px;
  color: var(--c-muted);
}

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

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

/* 图片容器 */
.hero-media,
.matrix-media,
.section-media,
.timeline-figure,
.content-figure,
.about-media,
.page-hero-figure {
  display: block;
  overflow: hidden;
  background: #e7e2d8;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

.hero-media img,
.matrix-media img,
.section-media img,
.timeline-figure img,
.content-figure img,
.about-media img,
.page-hero-figure img {
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* 相关入口条 */
.related-bar,
.entry-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 28px;
  padding: 16px 18px;
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

.related-bar a,
.entry-link,
.entry-links a {
  display: inline-block;
  padding: 8px 14px;
  font-size: 15px;
  color: var(--c-text);
  background: #f1eee6;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-sm);
}

.related-bar a:hover,
.entry-link:hover,
.entry-links a:hover {
  color: var(--c-accent);
  border-color: var(--c-accent);
}

/* --------------------------------------------------------------------------
   4. pages — 首页与各内页业务模块
   -------------------------------------------------------------------------- */

/* ---- 首页 ---- */

.hero {
  background: var(--c-ink);
  color: #eae6de;
  padding: 56px 0 60px;
}

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: 44px;
  align-items: center;
}

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

.hero-eyebrow {
  margin: 0 0 14px;
  font-size: 13px;
  letter-spacing: 0.14em;
  color: var(--c-accent);
}

.hero-text h1 {
  margin: 0 0 18px;
  font-size: 40px;
  line-height: 1.25;
  color: #ffffff;
}

.hero-lead {
  margin: 0 0 26px;
  max-width: 34em;
  font-size: 17px;
  line-height: 1.85;
  color: #c3bfb6;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 28px;
}

.hero-stages {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  padding-top: 20px;
  border-top: 1px solid var(--c-line-dark);
}

.hero-stages a {
  display: inline-block;
  padding: 7px 13px;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: #cfcbc2;
  border: 1px solid var(--c-line-dark);
  border-radius: var(--radius-sm);
}

.hero-stages a:hover {
  color: #ffffff;
  border-color: var(--c-accent);
}

.hero-media img {
  width: 100%;
  aspect-ratio: 16 / 11;
  object-fit: cover;
}

/* 服务矩阵表区 */
.table-toolbar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
}

.table-hint {
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--c-muted);
}

.sort-toggle {
  min-height: 44px;
  padding: 10px 18px;
  font-size: 15px;
  font-weight: 500;
  color: var(--c-ink);
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  cursor: pointer;
}

.sort-toggle:hover {
  border-color: var(--c-accent);
  color: var(--c-accent);
}

.matrix-media {
  margin-top: 24px;
}

.matrix-media img {
  width: 100%;
  aspect-ratio: 21 / 9;
  object-fit: cover;
}

/* 交付标准三联 */
.delivery-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.delivery-col {
  padding: 24px 22px;
  transition: transform 0.16s ease, border-color 0.16s ease;
}

.delivery-col:hover {
  transform: translateY(-2px);
  border-color: #c8c1b3;
}

.delivery-col h3 {
  margin: 0 0 10px;
}

.delivery-col p {
  margin: 0 0 16px;
  color: var(--c-muted);
  font-size: 15px;
}

/* 内容方法摘要 */
.summary-card {
  padding: 24px 22px;
  border-left: 3px solid var(--c-accent);
}

.summary-lead {
  margin: 0;
  font-size: 18px;
  line-height: 1.8;
  color: var(--c-text);
}

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

.method-point {
  padding: 20px 20px 22px;
  transition: transform 0.16s ease, border-color 0.16s ease;
}

.method-point:hover {
  transform: translateY(-2px);
  border-color: #c8c1b3;
}

.method-point h3 {
  margin: 0 0 8px;
  font-size: 18px;
}

.method-point p {
  margin: 0;
  font-size: 15px;
  color: var(--c-muted);
}

/* 合作须知列表 */
.notice-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.notice-item a {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  padding: 15px 18px;
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-1);
  transition: transform 0.16s ease, border-color 0.16s ease;
}

.notice-item a:hover {
  transform: translateY(-2px);
  border-color: #c8c1b3;
}

.notice-name {
  font-weight: 500;
  color: var(--c-text);
}

.notice-time {
  margin-left: auto;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--c-muted);
}

/* 合作对接准备区 */
.contact-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 28px;
  padding: 34px 30px;
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-1);
}

.contact-intro {
  min-width: 0;
}

.contact-intro h2 {
  margin: 0 0 12px;
}

.contact-intro p {
  color: var(--c-muted);
}

.contact-checklist {
  min-width: 0;
}

.contact-checklist h3 {
  margin: 0 0 14px;
  font-size: 18px;
}

.prepare-list {
  counter-reset: prep;
  gap: 12px;
}

.prepare-list li {
  position: relative;
  padding-left: 34px;
  color: var(--c-text);
}

.prepare-list li::before {
  counter-increment: prep;
  content: counter(prep);
  position: absolute;
  left: 0;
  top: 0.28em;
  width: 22px;
  height: 22px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  font-weight: 600;
  color: #ffffff;
  background: var(--c-accent);
  border-radius: 3px;
}

/* ---- 内页公共：标题区与两列布局 ---- */

.page-hero {
  background: var(--c-ink-2);
  color: #cfcbc2;
  padding: 26px 0 30px;
  margin-bottom: 40px;
}

.page-hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 0.8fr);
  gap: 32px;
  align-items: center;
}

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

.page-hero-lead,
.page-lead {
  margin: 0 0 14px;
  font-size: 17px;
  line-height: 1.85;
  color: #c3bfb6;
}

.page-hero-text .page-hero-lead {
  margin-bottom: 12px;
}

.page-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 20px;
  margin: 0;
  padding: 0;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: #a7aeb8;
}

.meta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 20px;
  margin: 0;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: #a7aeb8;
}

.meta-item {
  display: inline-block;
}

.page-hero-figure img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

/* 两列：默认主内容在前，aside 在后 */
.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  gap: 36px;
  align-items: start;
  padding-top: 4px;
}

/* 左侧栏变体：侧栏在前（sidebar-left 可能位于布局容器或祖先节点） */
.sidebar-left .page-layout,
.page-layout.sidebar-left {
  grid-template-columns: 260px minmax(0, 1fr);
}

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

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

/* 内页阅读列 */
.reading-col {
  margin-left: auto;
  margin-right: auto;
}

/* ---- 服务矩阵页 ---- */

.service-list > h2 {
  margin: 0 0 8px;
}

.service-list .section-media {
  margin: 22px 0 26px;
}

.service-list .section-media img {
  width: 100%;
  aspect-ratio: 21 / 9;
  object-fit: cover;
}

.service-item {
  padding: 26px 24px;
  margin-bottom: 18px;
  transition: transform 0.16s ease, border-color 0.16s ease;
}

.service-item:hover {
  transform: translateY(-2px);
  border-color: #c8c1b3;
}

.service-item-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}

.service-item-title {
  margin: 0;
  font-size: 21px;
}

.service-item-scene {
  margin: 0 0 18px;
  color: var(--c-muted);
}

.service-item-deliver {
  padding: 16px 18px;
  background: #faf8f3;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-sm);
}

.sub-title {
  margin: 0 0 10px;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--c-text);
}

.service-item-pre {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 16px 0 0;
  font-size: 15px;
  color: var(--c-muted);
}

.pre-label {
  flex: none;
  padding: 2px 9px;
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.04em;
  color: #5b6470;
  background: rgba(138, 143, 152, 0.14);
  border: 1px solid rgba(138, 143, 152, 0.34);
  border-radius: 3px;
}

/* 侧栏块 */
.side-block {
  padding: 20px 18px;
  margin-bottom: 18px;
}

.side-title {
  margin: 0 0 10px;
  font-size: 17px;
}

.side-note,
.side-text {
  margin: 0 0 12px;
  font-size: 15px;
  color: var(--c-muted);
}

.order-list {
  counter-reset: order;
  gap: 10px;
}

.order-list li {
  position: relative;
  padding-left: 30px;
  font-size: 15px;
  color: var(--c-text);
}

.order-list li::before {
  counter-increment: order;
  content: counter(order);
  position: absolute;
  left: 0;
  top: 0.24em;
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  font-weight: 600;
  color: var(--c-accent);
  border: 1px solid rgba(200, 132, 42, 0.4);
  border-radius: 3px;
}

/* ---- 交付标准页 ---- */

.side-card {
  padding: 20px 18px;
  margin-bottom: 18px;
}

.side-card-title {
  margin: 0 0 10px;
  font-size: 17px;
}

.content-section {
  margin-bottom: 44px;
}

.section-title {
  margin: 0 0 8px;
  font-size: 28px;
}

.section-media {
  margin: 22px 0 26px;
}

.section-media img {
  width: 100%;
  aspect-ratio: 21 / 9;
  object-fit: cover;
}

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

.deliverable-item {
  padding: 22px 20px;
  transition: transform 0.16s ease, border-color 0.16s ease;
}

.deliverable-item:hover {
  transform: translateY(-2px);
  border-color: #c8c1b3;
}

.deliverable-name {
  margin: 0 0 8px;
  font-size: 18px;
}

.deliverable-desc {
  margin: 0 0 14px;
  font-size: 15px;
  color: var(--c-muted);
}

.deliverable-points li {
  font-size: 15px;
}

.acceptance-block {
  padding: 22px 20px;
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-left: 3px solid var(--c-accent);
  border-radius: var(--radius);
  box-shadow: var(--shadow-1);
}

.acceptance-text {
  margin: 0 0 14px;
  color: var(--c-muted);
}

.revision-block {
  margin-top: 20px;
  padding: 22px 20px;
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-1);
}

.subsection-title {
  margin: 0 0 10px;
  font-size: 18px;
}

.revision-text {
  margin: 0;
  color: var(--c-muted);
}

/* ---- 合作流程页 ---- */

.section-timeline .section-head,
.section-handoff .section-head,
.section-pitfalls .section-head {
  margin-bottom: 24px;
}

.timeline-figure {
  margin-bottom: 30px;
}

.timeline-figure img {
  width: 100%;
  aspect-ratio: 21 / 9;
  object-fit: cover;
}

.timeline-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.timeline-item {
  position: relative;
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 20px;
  padding: 0 0 32px;
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: 27px;
  top: 46px;
  bottom: 0;
  width: 1px;
  background: var(--c-line);
}

.timeline-item:last-child::before {
  display: none;
}

.timeline-seq {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  height: 46px;
  font-size: 15px;
  font-weight: 600;
  color: #ffffff;
  background: var(--c-ink);
  border-radius: var(--radius-sm);
}

.timeline-body {
  min-width: 0;
  padding: 18px 22px 22px;
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-1);
}

.timeline-name {
  margin: 0 0 8px;
  font-size: 20px;
}

.timeline-text {
  margin: 0 0 16px;
  color: var(--c-muted);
}

.timeline-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--c-line);
}

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

.timeline-col-title {
  margin: 0 0 6px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--c-accent);
}

.timeline-col p {
  margin: 0;
  font-size: 15px;
  color: var(--c-muted);
}

.handoff-table-wrap {
  margin-top: 4px;
}

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

.pitfall-item {
  padding: 22px 20px;
  transition: transform 0.16s ease, border-color 0.16s ease;
}

.pitfall-item:hover {
  transform: translateY(-2px);
  border-color: #c8c1b3;
}

.pitfall-name {
  margin: 0 0 10px;
  font-size: 18px;
}

.pitfall-desc {
  margin: 0 0 12px;
  font-size: 15px;
  color: var(--c-muted);
}

.pitfall-action {
  margin: 0;
  padding-top: 12px;
  font-size: 15px;
  color: var(--c-text);
  border-top: 1px solid var(--c-line);
}

.section-related {
  padding: 0 0 8px;
}

.related-list {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.related-list a {
  display: inline-block;
  padding: 10px 16px;
  font-size: 15px;
  color: var(--c-text);
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

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

/* ---- 内容方法页 ---- */

.summary-section .section-title,
.principle-section .section-title,
.example-section .section-title,
.pitfall-section .section-title,
.related-section .section-title {
  margin-bottom: 18px;
}

.summary-conclusion {
  margin: 0 0 16px;
  font-size: 18px;
  line-height: 1.8;
  color: var(--c-text);
}

.summary-points {
  padding-top: 16px;
  border-top: 1px solid var(--c-line);
}

.content-figure {
  margin-bottom: 28px;
}

.content-figure img {
  width: 100%;
  aspect-ratio: 21 / 9;
  object-fit: cover;
}

.principle-block {
  margin-bottom: 26px;
}

.principle-block:last-child {
  margin-bottom: 0;
}

.principle-block p {
  color: var(--c-muted);
}

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

.example-card {
  padding: 22px 20px;
  transition: transform 0.16s ease, border-color 0.16s ease;
}

.example-card:hover {
  transform: translateY(-2px);
  border-color: #c8c1b3;
}

.example-scene {
  margin: 0 0 16px;
  font-size: 15px;
  color: var(--c-muted);
}

.example-structure {
  counter-reset: step;
  gap: 10px;
  padding-top: 14px;
  border-top: 1px solid var(--c-line);
}

.structure-item {
  position: relative;
  padding-left: 30px;
  font-size: 15px;
  color: var(--c-text);
}

.structure-item::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0.22em;
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  font-weight: 600;
  color: #ffffff;
  background: var(--c-ink);
  border-radius: 3px;
}

.pitfall-section .pitfall-list {
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.related-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.related-links a {
  display: inline-block;
  padding: 10px 16px;
  font-size: 15px;
  color: var(--c-text);
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

.related-links a:hover {
  color: var(--c-accent);
  border-color: var(--c-accent);
}

/* ---- 常见问题页 ---- */

.anchor-bar {
  background: var(--c-card);
  border-top: 1px solid var(--c-line);
  border-bottom: 1px solid var(--c-line);
}

.anchor-bar-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  padding-top: 14px;
  padding-bottom: 14px;
}

.anchor-bar-inner a {
  display: inline-block;
  padding: 8px 14px;
  font-size: 14px;
  color: var(--c-text);
  background: #f1eee6;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-sm);
}

.anchor-bar-inner a:hover {
  color: var(--c-accent);
  border-color: var(--c-accent);
}

.page-body {
  padding-top: 40px;
}

.faq-group {
  max-width: 860px;
  margin: 0 auto 44px;
}

.faq-group:last-of-type {
  margin-bottom: 0;
}

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

.faq-group .section-head h2 {
  font-size: 24px;
}

/* ---- 关于页 ---- */

.about-position,
.about-collab,
.about-principles,
.about-boundary {
  margin-bottom: 44px;
}

.about-position p,
.about-collab p,
.about-principles p,
.about-boundary p {
  color: var(--c-muted);
}

.scope-tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}

.scope-tag {
  display: inline-block;
  padding: 6px 13px;
  font-size: 14px;
  color: var(--c-text);
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-sm);
}

.about-media {
  margin: 22px 0 26px;
}

.about-media img {
  width: 100%;
  aspect-ratio: 21 / 9;
  object-fit: cover;
}

.collab-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
  margin-top: 20px;
}

.collab-item {
  padding: 20px 18px;
  transition: transform 0.16s ease, border-color 0.16s ease;
}

.collab-item:hover {
  transform: translateY(-2px);
  border-color: #c8c1b3;
}

.collab-name {
  margin: 0 0 8px;
  font-size: 17px;
}

.collab-item p {
  margin: 0;
  font-size: 15px;
}

.principle-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-top: 18px;
}

.principle-item {
  padding: 20px 20px 22px;
  border-left: 3px solid var(--c-accent);
}

.principle-name {
  margin: 0 0 8px;
  font-size: 18px;
}

.principle-item p {
  margin: 0;
  font-size: 15px;
}

.boundary-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-top: 18px;
}

.boundary-item {
  padding: 20px 20px 22px;
}

.boundary-name {
  margin: 0 0 8px;
  font-size: 17px;
}

.boundary-item p {
  margin: 0;
  font-size: 15px;
}

.aside-block {
  padding: 20px 18px;
  margin-bottom: 18px;
}

.aside-title {
  margin: 0 0 10px;
  font-size: 17px;
}

.aside-link-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.aside-link-list a {
  font-size: 15px;
  color: var(--c-accent);
}

.aside-link-list a:hover {
  color: var(--c-ink);
}

/* ---- 404 ---- */

.error-main {
  padding: 56px 0 24px;
}

.error-block {
  max-width: var(--reading);
  margin: 0 auto;
  padding: 40px 32px;
  text-align: center;
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-1);
}

.error-code {
  margin: 0 0 10px;
  font-size: 13px;
  letter-spacing: 0.18em;
  color: var(--c-accent);
}

.error-title {
  margin: 0 0 14px;
  font-size: 34px;
}

.error-desc {
  margin: 0 0 26px;
  color: var(--c-muted);
}

.error-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

.error-actions .btn-ghost {
  color: var(--c-text);
  border-color: var(--c-line);
}

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

.error-links {
  max-width: var(--reading);
  margin: 40px auto 0;
}

.error-link-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 16px;
}

.error-link-list a {
  display: block;
  padding: 12px 16px;
  font-size: 15px;
  color: var(--c-text);
  background: var(--c-card);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

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

/* --------------------------------------------------------------------------
   5. responsive — 1024 / 768 / 480
   -------------------------------------------------------------------------- */

@media (max-width: 1024px) {
  h1,
  .hero-text h1 {
    font-size: 34px;
  }

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

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

  .page-hero-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 22px;
  }

  .footer-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 28px;
  }

  .page-layout,
  .sidebar-left .page-layout,
  .page-layout.sidebar-left {
    grid-template-columns: minmax(0, 1fr) 260px;
    gap: 28px;
  }

  .delivery-grid,
  .method-points,
  .pitfall-list,
  .collab-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

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

@media (max-width: 768px) {
  body {
    font-size: 16px;
  }

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

  h2,
  .section-title {
    font-size: 23px;
  }

  h3 {
    font-size: 18px;
  }

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

  .container {
    padding: 0 18px;
  }

  .nav-toggle {
    display: block;
  }

  .nav-list {
    display: none;
  }

  .nav-list.is-open {
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .section {
    padding: 40px 0;
  }

  .hero {
    padding: 36px 0 42px;
  }

  .page-hero {
    padding: 20px 0 24px;
    margin-bottom: 28px;
  }

  .breadcrumb,
  .page-header {
    padding-left: 18px;
    padding-right: 18px;
  }

  .breadcrumb {
    padding-top: 16px;
  }

  .page-layout,
  .sidebar-left .page-layout,
  .page-layout.sidebar-left {
    grid-template-columns: minmax(0, 1fr);
    gap: 26px;
  }

  /* 移动端主内容先于辅助栏 */
  .sidebar-left .sidebar {
    order: 2;
  }

  .sidebar-left .content-main {
    order: 1;
  }

  .side-column,
  .sidebar,
  .layout-aside {
    order: 2;
  }

  .main-column,
  .content-main,
  .layout-main {
    order: 1;
  }

  .delivery-grid,
  .method-points,
  .pitfall-list,
  .collab-grid,
  .deliverable-list,
  .example-grid,
  .boundary-list,
  .error-link-list,
  .timeline {
    grid-template-columns: minmax(0, 1fr);
  }

  .footer-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 26px;
    padding-top: 36px;
    padding-bottom: 28px;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
  }

  .contact-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 22px;
    padding: 26px 20px;
  }

  .timeline-item {
    grid-template-columns: 44px minmax(0, 1fr);
    gap: 14px;
    padding-bottom: 24px;
  }

  .timeline-item::before {
    left: 21px;
  }

  .timeline-seq {
    width: 44px;
    height: 40px;
    font-size: 14px;
  }

  .timeline-body {
    padding: 16px 18px 18px;
  }

  .timeline-cols {
    grid-template-columns: minmax(0, 1fr);
    gap: 14px;
  }

  .faq-group {
    margin-bottom: 34px;
  }

  .service-item {
    padding: 22px 18px;
  }

  .notice-item a {
    flex-wrap: wrap;
  }

  .notice-time {
    margin-left: 0;
    width: 100%;
  }

  /* 移动底部固定导航 */
  .mobile-bottom-nav,
  .mobile-tabbar {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 70;
    background: var(--c-ink);
    border-top: 1px solid var(--c-line-dark);
    padding-bottom: env(safe-area-inset-bottom, 0);
  }

  .mobile-bottom-nav a,
  .mobile-tabbar a {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: var(--tabbar-h);
    padding: 8px 4px;
    font-size: 13px;
    line-height: 1.3;
    text-align: center;
    color: #c9c5bd;
  }

  .mobile-bottom-nav a:hover,
  .mobile-tabbar a:hover {
    color: #ffffff;
  }

  .site-main {
    padding-bottom: calc(var(--tabbar-h) + 28px);
  }

  .site-footer {
    padding-bottom: calc(var(--tabbar-h) + env(safe-area-inset-bottom, 0px));
  }
}

@media (max-width: 480px) {
  h1,
  .hero-text h1 {
    font-size: 25px;
  }

  .page-title {
    font-size: 23px;
  }

  .section-title {
    font-size: 21px;
  }

  .container {
    padding: 0 16px;
  }

  .breadcrumb,
  .page-header {
    padding-left: 16px;
    padding-right: 16px;
  }

  .btn {
    width: 100%;
  }

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

  .hero-stages {
    flex-wrap: nowrap;
    overflow-x: auto;
    padding-bottom: 6px;
  }

  .hero-stages a {
    flex: none;
  }

  .anchor-bar-inner {
    flex-wrap: nowrap;
    overflow-x: auto;
  }

  .anchor-bar-inner a {
    flex: none;
  }

  .error-block {
    padding: 30px 20px;
  }

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

  .service-item-head {
    align-items: flex-start;
  }

  .related-bar,
  .entry-bar {
    flex-direction: column;
    align-items: stretch;
  }

  .related-bar a,
  .entry-link,
  .entry-links a {
    text-align: center;
  }
}

/* 程序验收反馈：修复网格孤项 */
@media (min-width: 769px) {
  .footer-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}