/* ============================================================
   黑料718 · 全站样式表
   黑白影像风 · 单色动作红
   分组：base / layout / components / pages / responsive
   ============================================================ */

/* ============================================================
   Base —— 全局基础
   ============================================================ */

:root {
  --ink: #0a0a0a;
  --paper: #f2f2f2;
  --gray: #d9d9d9;
  --light-gray: #b0b0b0;
  --dark-bg: #1a1a1a;
  --divider: #e6e6e6;
  --accent: #c62828;
  --white: #ffffff;
  --container: 1140px;
  --radius: 8px;
  --font-sans: "Noto Sans SC", "Source Han Sans SC", "Microsoft YaHei", "PingFang SC", sans-serif;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink);
  background: var(--paper);
}

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

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

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

ul,
ol {
  list-style: none;
}

h1,
h2,
h3,
h4 {
  font-weight: 700;
  line-height: 1.3;
}

h1 {
  font-size: 36px;
}

h2 {
  font-size: 24px;
}

h3 {
  font-size: 18px;
}

p {
  margin-bottom: 0;
}

/* ============================================================
   Layout —— 全站骨架
   ============================================================ */

.site-body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--paper);
}

.site-header {
  background: var(--white);
  border-bottom: 1px solid var(--divider);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  font-size: 22px;
  font-weight: 800;
  letter-spacing: 0.02em;
  flex-shrink: 0;
}

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

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

.slogan {
  font-size: 13px;
  color: var(--light-gray);
  white-space: nowrap;
}

.site-nav ul {
  display: flex;
  gap: 28px;
}

.site-nav a {
  font-size: 15px;
  font-weight: 500;
  color: #333;
  padding: 6px 2px;
  border-bottom: 2px solid transparent;
}

.site-nav a:hover {
  color: var(--ink);
  border-bottom-color: var(--accent);
}

.site-nav a.is-current {
  color: var(--ink);
  border-bottom-color: var(--accent);
  font-weight: 700;
}

.site-main {
  flex: 1;
  width: 100%;
}

.inner-main {
  max-width: var(--container);
  margin: 0 auto;
  padding: 32px 24px 64px;
  width: 100%;
}

/* 面包屑 */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--light-gray);
  margin-bottom: 24px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--divider);
}

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

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

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

/* 页面标题区 */
.page-header {
  margin-bottom: 24px;
}

.page-title {
  font-size: 36px;
  font-weight: 800;
  color: var(--ink);
  line-height: 1.25;
}

.page-intro {
  font-size: 16px;
  color: #555;
  margin-top: 12px;
  max-width: 720px;
}

.page-title-block .page-intro,
.page-title-area .page-intro {
  font-size: 16px;
  color: #555;
  margin-top: 12px;
  max-width: 720px;
}

/* ============================================================
   Components —— 通用组件
   ============================================================ */

/* 按钮 */
.btn-primary,
.btn-secondary {
  display: inline-block;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

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

.btn-primary:hover {
  background: #a12424;
  border-color: #a12424;
  color: var(--white);
}

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

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

/* 图片容器 */
figure {
  margin: 0;
}

figure img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* 页脚 */
.site-footer {
  background: var(--dark-bg);
  color: #cccccc;
  margin-top: auto;
}

.footer-grid {
  max-width: var(--container);
  margin: 0 auto;
  padding: 48px 24px 32px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
}

.footer-col h3 {
  font-size: 16px;
  color: var(--white);
  margin-bottom: 16px;
  font-weight: 600;
}

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

.footer-col a {
  color: #cccccc;
  font-size: 14px;
}

.footer-col a:hover {
  color: var(--white);
}

.footer-bottom {
  max-width: var(--container);
  margin: 0 auto;
  padding: 20px 24px 32px;
  border-top: 1px solid #333;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 24px;
  font-size: 13px;
  color: #888888;
}

/* ============================================================
   Pages —— 首页
   ============================================================ */

/* ---- 首屏分类目录 ---- */
.hero-catalog {
  background: var(--ink);
  color: var(--white);
  padding: 64px 0 0;
  position: relative;
  overflow: hidden;
}

.hero-catalog {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 48px;
  max-width: var(--container);
  margin: 0 auto;
  padding-left: 24px;
  padding-right: 24px;
  padding-bottom: 0;
  align-items: start;
}

.hero-copy {
  padding-bottom: 64px;
}

.hero-copy h1 {
  font-size: 40px;
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 20px;
  color: var(--white);
}

.hero-copy p {
  font-size: 16px;
  color: #cccccc;
  margin-bottom: 28px;
  max-width: 480px;
}

.hero-copy .btn-primary {
  background: var(--accent);
  border-color: var(--accent);
}

.hero-cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  padding-bottom: 64px;
}

.hero-card {
  background: #222;
  border: 1px solid #333;
  border-radius: var(--radius);
  padding: 20px 24px;
  display: block;
  transition: background 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
}

.hero-card:hover {
  background: #2a2a2a;
  border-color: var(--accent);
  transform: translateY(-2px);
}

.hero-card h2 {
  font-size: 18px;
  color: var(--white);
  margin-bottom: 6px;
}

.hero-card p {
  font-size: 14px;
  color: #999999;
  margin-bottom: 10px;
  line-height: 1.5;
}

.card-tag {
  display: inline-block;
  font-size: 12px;
  color: var(--light-gray);
  border: 1px solid #444;
  border-radius: 4px;
  padding: 2px 10px;
}

.hero-figure {
  grid-column: 1 / -1;
  width: 100%;
  height: 320px;
  position: relative;
}

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

/* ---- 高价值推荐条 ---- */
.briefing-recommend {
  max-width: var(--container);
  margin: 0 auto;
  padding: 64px 24px;
}

.briefing-recommend h2 {
  font-size: 24px;
  margin-bottom: 32px;
  position: relative;
  padding-left: 16px;
}

.briefing-recommend h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background: var(--accent);
}

.briefing-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.briefing-item {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 28px;
  transition: box-shadow 0.2s ease, border-color 0.2s ease;
}

.briefing-item:hover {
  border-color: var(--light-gray);
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
}

.briefing-item h3 {
  font-size: 18px;
  margin-bottom: 12px;
}

.briefing-item p {
  font-size: 14px;
  color: #555;
  margin-bottom: 16px;
  line-height: 1.65;
}

.briefing-item a {
  font-size: 14px;
  font-weight: 600;
  color: var(--accent);
}

.briefing-item a:hover {
  text-decoration: underline;
}

/* ---- 服务矩阵摘要 ---- */
.service-matrix-summary {
  background: var(--white);
  border-top: 1px solid var(--divider);
  border-bottom: 1px solid var(--divider);
  padding: 64px 0;
}

.service-matrix-summary > h2,
.service-matrix-summary > p {
  max-width: var(--container);
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

.service-matrix-summary h2 {
  margin-bottom: 12px;
}

.service-matrix-summary > p {
  color: #555;
  margin-bottom: 40px;
  max-width: 720px;
}

.matrix-grid {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.matrix-card {
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 24px;
  background: var(--paper);
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.matrix-card:hover {
  border-color: var(--light-gray);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.matrix-card h3 {
  font-size: 17px;
  margin-bottom: 10px;
}

.matrix-card .scenario {
  font-size: 14px;
  color: #555;
  margin-bottom: 14px;
  line-height: 1.6;
}

.matrix-card ul.deliverables {
  border-top: 1px solid var(--divider);
  padding-top: 12px;
}

.matrix-card ul.deliverables li {
  font-size: 13px;
  color: var(--light-gray);
  padding: 4px 0;
  position: relative;
  padding-left: 14px;
}

.matrix-card ul.deliverables li::before {
  content: "·";
  position: absolute;
  left: 2px;
  color: var(--accent);
  font-weight: 700;
}

/* ---- 合作流程四阶段 ---- */
.process-preview {
  max-width: var(--container);
  margin: 0 auto;
  padding: 64px 24px;
}

.process-preview > h2 {
  margin-bottom: 40px;
  position: relative;
  padding-left: 16px;
}

.process-preview > h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background: var(--accent);
}

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

.process-timeline ol {
  position: relative;
  padding-left: 0;
}

.process-timeline ol li {
  position: relative;
  padding: 0 0 36px 32px;
}

.process-timeline ol li::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 4px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--paper);
  box-shadow: 0 0 0 2px var(--accent);
}

.process-timeline ol li:not(:last-child)::after {
  content: "";
  position: absolute;
  left: 11px;
  top: 20px;
  bottom: 0;
  width: 2px;
  background: var(--divider);
}

.process-timeline ol li h3 {
  font-size: 18px;
  margin-bottom: 6px;
}

.process-timeline ol li p {
  font-size: 14px;
  color: #555;
  line-height: 1.6;
}

.process-checklist {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 28px;
}

.process-checklist h3 {
  font-size: 18px;
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--divider);
}

.process-checklist ul li {
  padding: 10px 0;
  border-bottom: 1px solid var(--divider);
  font-size: 14px;
  color: #555;
  line-height: 1.5;
}

.process-checklist ul li:last-child {
  border-bottom: none;
}

.process-checklist ul li strong {
  color: var(--ink);
  font-weight: 600;
}

.process-checklist .btn-secondary {
  margin-top: 20px;
  width: 100%;
  text-align: center;
}

/* ---- 参考导航与开始指南 ---- */
.guide-nav {
  background: var(--white);
  border-top: 1px solid var(--divider);
  padding: 64px 0;
}

.guide-nav > h2 {
  max-width: var(--container);
  margin: 0 auto 40px;
  padding: 0 24px;
  position: relative;
  padding-left: 40px;
}

.guide-nav > h2::before {
  content: "";
  position: absolute;
  left: 24px;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background: var(--accent);
}

.guide-grid {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.guide-card {
  display: block;
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 28px;
  background: var(--paper);
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.guide-card:hover {
  border-color: var(--light-gray);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.guide-card h3 {
  font-size: 18px;
  margin-bottom: 10px;
}

.guide-card p {
  font-size: 14px;
  color: #555;
  line-height: 1.6;
}

/* ---- 联系入口 ---- */
.contact-entry {
  max-width: var(--container);
  margin: 0 auto;
  padding: 64px 24px;
  text-align: center;
}

.contact-entry h2 {
  font-size: 24px;
  margin-bottom: 12px;
}

.contact-entry p {
  font-size: 15px;
  color: #555;
  margin-bottom: 24px;
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}

/* ============================================================
   Pages —— 核心业务
   ============================================================ */

/* 服务边界说明 */
.service-boundary {
  margin-bottom: 48px;
}

.section-title {
  font-size: 22px;
  margin-bottom: 16px;
  position: relative;
  padding-left: 14px;
}

.section-title::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background: var(--accent);
}

.service-boundary p {
  font-size: 15px;
  color: #555;
  line-height: 1.75;
  max-width: 860px;
}

/* 服务矩阵 */
.service-matrix {
  margin-bottom: 56px;
}

.service-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.service-card {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 28px;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.service-card:hover {
  border-color: var(--light-gray);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.service-card h3 {
  font-size: 19px;
  margin-bottom: 10px;
}

.service-scene {
  font-size: 13px;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 12px;
}

.service-desc {
  font-size: 14px;
  color: #555;
  margin-bottom: 16px;
  line-height: 1.65;
}

.service-deliverable {
  font-size: 13px;
  color: var(--light-gray);
  border-top: 1px solid var(--divider);
  padding-top: 12px;
  line-height: 1.5;
}

.service-deliverable::before {
  content: "交付物：";
  color: var(--ink);
  font-weight: 600;
}

/* 任务示例 */
.task-examples {
  margin-bottom: 56px;
}

.example-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.example-card {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 28px;
}

.example-card h3 {
  font-size: 18px;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--divider);
}

.example-input,
.example-output {
  font-size: 14px;
  color: #555;
  line-height: 1.65;
  margin-bottom: 10px;
}

.example-input::before {
  content: "输入需求：";
  color: var(--ink);
  font-weight: 600;
  display: block;
  font-size: 13px;
  color: var(--light-gray);
  margin-bottom: 4px;
}

.example-output::before {
  content: "输出结果：";
  display: block;
  font-size: 13px;
  color: var(--light-gray);
  margin-bottom: 4px;
}

/* 界面预览 */
.interface-preview {
  margin-bottom: 56px;
}

.preview-intro {
  font-size: 15px;
  color: #555;
  margin-bottom: 24px;
  max-width: 720px;
}

.preview-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.preview-item {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  overflow: hidden;
}

.preview-item img {
  width: 100%;
  height: 200px;
  object-fit: cover;
}

.preview-item figcaption {
  padding: 14px 16px;
  font-size: 13px;
  color: #555;
  line-height: 1.5;
}

/* 交付物与时限说明 */
.deliverable-info {
  margin-bottom: 56px;
}

.deliverable-list {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 8px 28px;
  margin-bottom: 16px;
}

.deliverable-list li {
  padding: 14px 0;
  border-bottom: 1px solid var(--divider);
  font-size: 14px;
  color: #555;
  line-height: 1.6;
  position: relative;
  padding-left: 20px;
}

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

.deliverable-list li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--accent);
}

.deliverable-note {
  font-size: 13px;
  color: var(--light-gray);
  line-height: 1.6;
}

/* 开始指南指引 */
.guide-entry {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 28px;
}

.guide-entry p {
  font-size: 14px;
  color: #555;
  margin-bottom: 20px;
  max-width: 720px;
}

.guide-links {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.guide-link {
  display: inline-block;
  padding: 10px 24px;
  border: 1px solid var(--ink);
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  transition: background 0.2s ease, color 0.2s ease;
}

.guide-link:hover {
  background: var(--ink);
  color: var(--white);
}

/* ============================================================
   Pages —— 工作方式
   ============================================================ */

/* 流程导航 */
.process-nav {
  margin-bottom: 48px;
}

.process-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  overflow: hidden;
}

.process-steps li {
  border-right: 1px solid var(--divider);
}

.process-steps li:last-child {
  border-right: none;
}

.process-steps a {
  display: block;
  padding: 16px 20px;
  text-align: center;
  font-size: 15px;
  font-weight: 500;
  color: var(--light-gray);
  transition: background 0.2s ease, color 0.2s ease;
}

.process-steps a:hover {
  background: var(--paper);
  color: var(--ink);
}

/* 阶段时间轴 */
.stage-timeline {
  margin-bottom: 56px;
}

.stage-timeline h2,
.task-checklist h2,
.work-scene h2,
.start-guide h2 {
  font-size: 24px;
  margin-bottom: 32px;
  position: relative;
  padding-left: 16px;
}

.stage-timeline h2::before,
.task-checklist h2::before,
.work-scene h2::before,
.start-guide h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background: var(--accent);
}

.stage-item {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 32px;
  padding: 32px 0;
  border-bottom: 1px solid var(--divider);
  position: relative;
}

.stage-item:last-child {
  border-bottom: none;
}

.stage-meta {
  position: relative;
  padding-left: 28px;
}

.stage-meta::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--paper);
  box-shadow: 0 0 0 2px var(--accent);
}

.stage-number {
  font-size: 13px;
  color: var(--light-gray);
  margin-bottom: 4px;
  font-weight: 600;
}

.stage-meta h3 {
  font-size: 20px;
}

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

.stage-goal {
  font-size: 15px;
  color: #555;
  margin-bottom: 16px;
  line-height: 1.7;
}

.stage-actions {
  margin-bottom: 14px;
}

.stage-actions li {
  font-size: 14px;
  color: #555;
  padding: 4px 0;
  padding-left: 18px;
  position: relative;
  line-height: 1.6;
}

.stage-actions li::before {
  content: "·";
  position: absolute;
  left: 4px;
  color: var(--accent);
  font-weight: 700;
}

.stage-output {
  font-size: 13px;
  color: var(--light-gray);
  line-height: 1.6;
}

.stage-output::before {
  content: "输出：";
  color: var(--ink);
  font-weight: 600;
}

/* 任务清单 */
.task-checklist {
  margin-bottom: 56px;
}

.task-groups {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.task-group {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 24px;
}

.task-group h3 {
  font-size: 17px;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--divider);
}

.task-list li {
  font-size: 14px;
  color: #555;
  padding: 8px 0;
  padding-left: 20px;
  position: relative;
  line-height: 1.6;
  border-bottom: 1px solid var(--divider);
}

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

.task-list li::before {
  content: "□";
  position: absolute;
  left: 0;
  color: var(--light-gray);
}

/* 工作场景 */
.work-scene {
  margin-bottom: 56px;
}

.scene-figure {
  border-radius: var(--radius);
  overflow: hidden;
  margin-bottom: 16px;
}

.scene-figure img {
  width: 100%;
  height: 320px;
  object-fit: cover;
}

.scene-figure figcaption {
  padding: 12px 16px;
  background: var(--white);
  border: 1px solid var(--divider);
  border-top: none;
  font-size: 13px;
  color: #555;
  line-height: 1.5;
}

.work-scene > p {
  font-size: 14px;
  color: #555;
  line-height: 1.7;
  max-width: 860px;
}

/* 开始指南 */
.start-guide {
  margin-bottom: 0;
}

.guide-steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.guide-steps li {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 28px;
  position: relative;
}

.guide-steps li h3 {
  font-size: 17px;
  margin-bottom: 10px;
}

.guide-steps li p {
  font-size: 14px;
  color: #555;
  line-height: 1.65;
  margin-bottom: 14px;
}

.guide-steps li a {
  font-size: 14px;
  font-weight: 600;
  color: var(--accent);
}

.guide-steps li a:hover {
  text-decoration: underline;
}

/* ============================================================
   Pages —— 内容参考
   ============================================================ */

/* 内容边界说明 */
.content-boundary-section {
  margin-bottom: 48px;
}

.content-boundary-section p {
  font-size: 15px;
  color: #555;
  line-height: 1.75;
  max-width: 860px;
}

/* 术语表 */
.term-section {
  margin-bottom: 56px;
}

.term-section h2,
.method-section h2,
.preview-section h2,
.related-links-section h2 {
  font-size: 24px;
  margin-bottom: 28px;
  position: relative;
  padding-left: 16px;
}

.term-section h2::before,
.method-section h2::before,
.preview-section h2::before,
.related-links-section h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background: var(--accent);
}

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

.term-card {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 20px;
  transition: border-color 0.2s ease;
}

.term-card:hover {
  border-color: var(--light-gray);
}

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

.term-card p {
  font-size: 13px;
  color: #555;
  line-height: 1.6;
}

/* 筛选方法 */
.method-section {
  margin-bottom: 56px;
}

.method-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.method-item {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 24px;
}

.method-item h3 {
  font-size: 17px;
  margin-bottom: 10px;
}

.method-item p {
  font-size: 14px;
  color: #555;
  line-height: 1.65;
  margin-bottom: 10px;
}

.method-note {
  font-size: 13px;
  color: var(--light-gray);
  border-top: 1px solid var(--divider);
  padding-top: 10px;
  line-height: 1.5;
}

/* 界面预览 */
.preview-section {
  margin-bottom: 56px;
}

/* 相关页面入口 */
.related-links-section {
  margin-bottom: 0;
}

.related-links-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.related-link-card {
  display: block;
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 24px;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.related-link-card:hover {
  border-color: var(--light-gray);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.related-link-card h3 {
  font-size: 17px;
  margin-bottom: 8px;
}

.related-link-card p {
  font-size: 14px;
  color: #555;
  line-height: 1.6;
}

/* ============================================================
   Pages —— 常见问题
   ============================================================ */

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

.faq-group h2 {
  font-size: 24px;
  margin-bottom: 24px;
  position: relative;
  padding-left: 16px;
}

.faq-group h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background: var(--accent);
}

.faq-list {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  overflow: hidden;
}

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

.faq-item:last-child {
  border-bottom: none;
}

.faq-item summary {
  padding: 18px 24px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  position: relative;
  padding-right: 48px;
  transition: background 0.2s ease;
  list-style: none;
}

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

.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 24px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 20px;
  color: var(--light-gray);
  font-weight: 400;
}

.faq-item[open] summary {
  background: var(--paper);
}

.faq-item[open] summary::after {
  content: "−";
}

.faq-item summary:hover {
  background: var(--paper);
}

.faq-item p {
  padding: 0 24px 20px;
  font-size: 14px;
  color: #555;
  line-height: 1.7;
}

/* FAQ 图片 */
.faq-image-block {
  margin-bottom: 48px;
}

.faq-figure {
  border-radius: var(--radius);
  overflow: hidden;
}

.faq-figure img {
  width: 100%;
  height: 280px;
  object-fit: cover;
}

.faq-figure figcaption {
  padding: 12px 16px;
  background: var(--white);
  border: 1px solid var(--divider);
  border-top: none;
  font-size: 13px;
  color: #555;
  line-height: 1.5;
}

/* 相关入口 */
.related-entry {
  margin-bottom: 0;
}

.related-entry h2 {
  font-size: 24px;
  margin-bottom: 24px;
  position: relative;
  padding-left: 16px;
}

.related-entry h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background: var(--accent);
}

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

.related-links a {
  display: block;
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 20px 24px;
  font-size: 15px;
  font-weight: 500;
  text-align: center;
  transition: border-color 0.2s ease, background 0.2s ease;
}

.related-links a:hover {
  border-color: var(--light-gray);
  background: var(--paper);
}

/* ============================================================
   Pages —— 联系
   ============================================================ */

/* 双栏布局：侧栏在左 */
.layout-shell.sidebar-left {
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 40px;
  align-items: start;
  margin-bottom: 56px;
}

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

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

/* 反馈流程 */
.feedback-steps {
  background: var(--ink);
  color: var(--white);
  border-radius: var(--radius);
  padding: 28px;
}

.feedback-steps h2 {
  font-size: 20px;
  margin-bottom: 12px;
  color: var(--white);
}

.feedback-steps > p {
  font-size: 14px;
  color: #bbbbbb;
  margin-bottom: 20px;
  line-height: 1.6;
}

.step-list li {
  padding: 14px 0;
  border-bottom: 1px solid #333;
}

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

.step-list h3 {
  font-size: 15px;
  color: var(--white);
  margin-bottom: 6px;
}

.step-list p {
  font-size: 13px;
  color: #999999;
  line-height: 1.6;
}

.feedback-steps > p:last-child {
  margin-top: 16px;
  margin-bottom: 0;
}

.feedback-steps > p:last-child a {
  color: var(--accent);
  font-weight: 600;
}

.feedback-steps > p:last-child a:hover {
  text-decoration: underline;
}

/* 需求自检工具 */
.checklist-tool {
  margin-bottom: 48px;
}

.checklist-tool h2,
.boundary-tips h2 {
  font-size: 22px;
  margin-bottom: 12px;
  position: relative;
  padding-left: 14px;
}

.checklist-tool h2::before,
.boundary-tips h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background: var(--accent);
}

.checklist-tool > p {
  font-size: 14px;
  color: #555;
  margin-bottom: 24px;
  max-width: 720px;
  line-height: 1.7;
}

.checklist-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  margin-bottom: 28px;
}

.check-item {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 20px;
}

.check-item h3 {
  font-size: 16px;
  margin-bottom: 8px;
}

.check-item p {
  font-size: 13px;
  color: #555;
  line-height: 1.6;
  margin-bottom: 10px;
}

.check-item ul {
  border-top: 1px solid var(--divider);
  padding-top: 8px;
}

.check-item ul li {
  font-size: 13px;
  color: var(--light-gray);
  padding: 3px 0;
  padding-left: 14px;
  position: relative;
  line-height: 1.5;
}

.check-item ul li::before {
  content: "·";
  position: absolute;
  left: 2px;
  color: var(--accent);
  font-weight: 700;
}

.checklist-note {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 20px 24px;
}

.checklist-note h3 {
  font-size: 15px;
  margin-bottom: 8px;
}

.checklist-note p {
  font-size: 13px;
  color: #555;
  line-height: 1.6;
}

/* 服务边界提示 */
.boundary-tips {
  margin-bottom: 0;
}

.boundary-tips > p {
  font-size: 14px;
  color: #555;
  margin-bottom: 16px;
  line-height: 1.7;
}

.boundary-list {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 8px 24px;
  margin-bottom: 16px;
}

.boundary-list li {
  padding: 12px 0;
  border-bottom: 1px solid var(--divider);
  font-size: 14px;
  color: #555;
  line-height: 1.6;
  position: relative;
  padding-left: 20px;
}

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

.boundary-list li::before {
  content: "×";
  position: absolute;
  left: 0;
  color: var(--accent);
  font-weight: 700;
}

.boundary-tips > p:last-child {
  font-size: 13px;
  color: var(--light-gray);
  line-height: 1.6;
}

/* 咨询场景图 */
.contact-visual {
  margin-bottom: 56px;
}

/* 下一步引导 */
.next-steps {
  margin-bottom: 0;
}

.next-steps h2 {
  font-size: 24px;
  margin-bottom: 12px;
  position: relative;
  padding-left: 16px;
}

.next-steps h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background: var(--accent);
}

.next-steps > p {
  font-size: 14px;
  color: #555;
  margin-bottom: 24px;
  max-width: 720px;
  line-height: 1.7;
}

.next-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.next-card {
  background: var(--white);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: 24px;
}

.next-card h3 {
  font-size: 17px;
  margin-bottom: 8px;
}

.next-card p {
  font-size: 14px;
  color: #555;
  line-height: 1.65;
}

.next-card p:last-child {
  margin-top: 10px;
  color: var(--light-gray);
  font-size: 13px;
}

/* ============================================================
   Pages —— 404
   ============================================================ */

.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 80px 24px;
  min-height: 60vh;
}

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

.error-code {
  font-size: 72px;
  font-weight: 800;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 16px;
}

.error-section h1 {
  font-size: 28px;
  margin-bottom: 16px;
}

.error-desc {
  font-size: 15px;
  color: #555;
  margin-bottom: 32px;
  line-height: 1.7;
}

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

/* ============================================================
   Responsive —— 响应式
   ============================================================ */

@media (max-width: 1024px) {
  .matrix-grid {
    grid-template-columns: repeat(2, 1fr);
  }

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

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

  .preview-grid .preview-item:last-child {
    grid-column: 1 / -1;
  }

  .preview-grid .preview-item:last-child img {
    height: 260px;
  }

  .layout-shell.sidebar-left {
    grid-template-columns: 280px 1fr;
    gap: 28px;
  }
}

@media (max-width: 768px) {
  /* 页头 */
  .header-inner {
    flex-wrap: wrap;
    padding: 12px 16px;
    gap: 8px;
  }

  .slogan {
    display: none;
  }

  .site-nav {
    width: 100%;
    order: 3;
  }

  .site-nav ul {
    display: flex;
    flex-wrap: wrap;
    gap: 4px 20px;
    padding-top: 8px;
    border-top: 1px solid var(--divider);
  }

  .site-nav a {
    font-size: 14px;
    padding: 6px 0;
  }

  /* 内页容器 */
  .inner-main {
    padding: 24px 16px 48px;
  }

  .page-title {
    font-size: 28px;
  }

  /* 首页 */
  .hero-catalog {
    grid-template-columns: 1fr;
    padding: 40px 16px 0;
    gap: 32px;
  }

  .hero-copy {
    padding-bottom: 0;
  }

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

  .hero-cards {
    padding-bottom: 40px;
  }

  .hero-figure {
    height: 220px;
  }

  .briefing-recommend,
  .process-preview,
  .contact-entry {
    padding: 48px 16px;
  }

  .briefing-grid,
  .process-layout {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .matrix-grid {
    grid-template-columns: 1fr;
    padding: 0 16px;
  }

  .service-matrix-summary > h2,
  .service-matrix-summary > p {
    padding-left: 16px;
    padding-right: 16px;
  }

  .guide-nav {
    padding: 48px 0;
  }

  .guide-nav > h2 {
    padding-left: 32px;
  }

  .guide-nav > h2::before {
    left: 16px;
  }

  .guide-grid {
    grid-template-columns: 1fr;
    padding: 0 16px;
    gap: 16px;
  }

  /* 核心业务 */
  .service-grid,
  .example-grid,
  .task-groups,
  .method-list {
    grid-template-columns: 1fr;
  }

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

  .preview-grid .preview-item:last-child {
    grid-column: auto;
  }

  .preview-grid .preview-item:last-child img {
    height: 200px;
  }

  .guide-links {
    flex-direction: column;
  }

  .guide-link {
    text-align: center;
  }

  /* 工作方式 */
  .process-steps {
    grid-template-columns: 1fr;
  }

  .process-steps li {
    border-right: none;
    border-bottom: 1px solid var(--divider);
  }

  .process-steps li:last-child {
    border-bottom: none;
  }

  .process-steps a {
    text-align: left;
    padding: 14px 20px;
  }

  .stage-item {
    grid-template-columns: 1fr;
    gap: 12px;
    padding: 24px 0;
  }

  .stage-meta {
    padding-left: 28px;
  }

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

  /* 内容参考 */
  .term-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }

  .related-links-grid,
  .related-links {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  /* FAQ */
  .faq-item summary {
    padding: 16px 16px;
    padding-right: 40px;
    font-size: 14px;
  }

  .faq-item summary::after {
    right: 16px;
  }

  .faq-item p {
    padding: 0 16px 16px;
    font-size: 13px;
  }

  /* 联系 */
  .layout-shell.sidebar-left {
    grid-template-columns: 1fr;
    gap: 32px;
  }

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

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

  /* 页脚 */
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 32px;
    padding: 40px 16px 24px;
  }

  .footer-bottom {
    padding: 16px 16px 24px;
    flex-direction: column;
    gap: 6px;
  }
}

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

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

  .hero-card {
    padding: 16px 18px;
  }

  .error-code {
    font-size: 56px;
  }

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

  .error-actions .btn-primary,
  .error-actions .btn-secondary {
    width: 100%;
    text-align: center;
  }
}