/* ==========================================================================
   午夜大片 · 整站样式
   base → layout → components → pages → responsive
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. base
   -------------------------------------------------------------------------- */

:root {
  --c-text: #1f2a44;
  --c-primary: #3d5af1;
  --c-accent: #ff7a45;
  --c-surface: #f4f6fb;
  --c-line: #e3e7f0;
  --c-text-soft: #5a6480;
  --c-white: #ffffff;
  --radius: 5px;
  --radius-sm: 4px;
  --content-w: 1120px;
  --pad-x: 24px;
  --shadow-card: 0 1px 2px rgba(31, 42, 68, 0.06);
  --shadow-lift: 0 6px 18px rgba(31, 42, 68, 0.1);
  --font: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "SFMono-Regular", "Cascadia Mono", Consolas, "Liberation Mono", monospace;
}

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

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

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.75;
  color: var(--c-text);
  background-color: var(--c-white);
}

h1,
h2,
h3,
h4,
p,
figure,
ol,
ul {
  margin: 0;
  padding: 0;
}

ul,
ol {
  list-style: none;
}

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

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

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

button {
  font-family: inherit;
  cursor: pointer;
}

p {
  color: var(--c-text);
}

strong {
  font-weight: 600;
}

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

/* 骨架：站级字体 / 颜色 / 容器宽度 ---------------------------------------- */

.site-body {
  font-family: var(--font);
  color: var(--c-text);
  background-color: var(--c-white);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

.site-nav {
  display: block;
}

.site-main {
  display: block;
  flex: 1 0 auto;
}

.site-footer {
  margin-top: 64px;
  background-color: var(--c-text);
  color: #d6dcec;
}

/* --------------------------------------------------------------------------
   2. layout
   -------------------------------------------------------------------------- */

.header-inner,
.footer-inner,
.hero-inner,
.page-layout,
.page-header,
.breadcrumb,
.error-panel,
.error-links {
  width: 100%;
  max-width: var(--content-w);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--pad-x);
  padding-right: var(--pad-x);
}

.header-inner {
  display: flex;
  align-items: center;
  gap: 24px;
  min-height: 68px;
}

/* 内页主容器：面包屑 / 标题 / 双栏统一宽度 -------------------------------- */

.inner-main {
  display: block;
  padding-top: 20px;
}

.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 40px;
  align-items: start;
  padding-top: 20px;
}

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

.page-side,
.content-aside,
.content-sidebar,
.page-aside {
  min-width: 0;
}

/* 侧栏在前的变体（当前 DOM 未使用，保留结构约定） */
.sidebar-left .page-layout {
  grid-template-columns: 300px minmax(0, 1fr);
}

/* --------------------------------------------------------------------------
   3. components
   -------------------------------------------------------------------------- */

/* --- 顶部信息条 ---------------------------------------------------------- */

.topbar,
.top-bar,
.top-note {
  background-color: var(--c-surface);
  border-bottom: 1px solid var(--c-line);
}

.topbar-text,
.top-bar-text,
.top-note {
  width: 100%;
  max-width: var(--content-w);
  margin: 0 auto;
  padding: 8px var(--pad-x);
  font-size: 13px;
  line-height: 1.5;
  color: var(--c-text-soft);
}

/* --- 页头品牌与导航 ------------------------------------------------------ */

.brand {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 2px;
  flex: 0 0 auto;
  color: var(--c-text);
}

.brand:hover {
  color: var(--c-primary);
}

.brand-name {
  font-size: 20px;
  font-weight: 700;
  line-height: 1.2;
  color: inherit;
}

.brand-slogan {
  font-size: 12px;
  line-height: 1.4;
  color: var(--c-text-soft);
}

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

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

.nav-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 14px;
  font-size: 15px;
  font-weight: 600;
  color: var(--c-text);
  border-bottom: 2px solid transparent;
  transition: color 0.18s ease, border-color 0.18s ease;
}

.nav-link:hover {
  color: var(--c-primary);
}

.nav-link.is-current {
  color: var(--c-primary);
  border-bottom-color: var(--c-accent);
}

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

.nav-toggle-bar {
  display: block;
  height: 2px;
  background-color: var(--c-text);
  border-radius: 1px;
}

/* --- 按钮 ---------------------------------------------------------------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 22px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius);
  border: 1px solid transparent;
  transition: background-color 0.18s ease, color 0.18s ease, border-color 0.18s ease, transform 0.18s ease;
}

.btn-primary {
  background-color: var(--c-primary);
  color: var(--c-white);
  border-color: var(--c-primary);
}

.btn-primary:hover {
  background-color: #2f47cf;
  border-color: #2f47cf;
  color: var(--c-white);
}

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

.btn-ghost:hover {
  color: var(--c-primary);
  border-color: var(--c-primary);
}

/* --- 通用区块头 ---------------------------------------------------------- */

.section {
  margin-top: 56px;
}

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

.section-title {
  font-size: 26px;
  font-weight: 700;
  line-height: 1.35;
  color: var(--c-text);
}

.section-desc,
.section-intro,
.section-note {
  margin-top: 8px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--c-text-soft);
  max-width: 68ch;
}

.section-more {
  margin-top: 20px;
  font-size: 15px;
}

.link-more {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-weight: 600;
  color: var(--c-primary);
  border-bottom: 1px solid transparent;
}

.link-more:hover {
  border-bottom-color: var(--c-accent);
}

/* --- 编号标签 ------------------------------------------------------------ */

.num-tag,
.direction-num,
.stage-num,
.stage-index,
.step-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 34px;
  height: 26px;
  padding: 0 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--c-primary);
  background-color: var(--c-surface);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-sm);
}

/* --- 面包屑 -------------------------------------------------------------- */

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

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

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

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

.breadcrumb-current {
  color: var(--c-text);
  font-weight: 600;
}

/* --- 内页标题区 ---------------------------------------------------------- */

.page-header {
  padding-top: 20px;
  padding-bottom: 22px;
  border-bottom: 1px solid var(--c-line);
}

.page-title {
  font-size: 32px;
  font-weight: 700;
  line-height: 1.3;
  color: var(--c-text);
}

.page-description {
  margin-top: 10px;
  font-size: 16px;
  line-height: 1.75;
  color: var(--c-text-soft);
  max-width: 68ch;
}

/* --- 图片容器 ------------------------------------------------------------ */

.media-figure,
.hero-figure,
.section-figure,
.faq-figure {
  margin: 0;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  background-color: var(--c-surface);
  overflow: hidden;
}

.media-figure img,
.hero-figure img,
.section-figure img,
.faq-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background-color: var(--c-surface);
}

.media-figure-wide img {
  aspect-ratio: 21 / 9;
}

.media-caption,
.hero-figure figcaption,
.section-figure figcaption,
.faq-figure figcaption {
  padding: 10px 14px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--c-text-soft);
  background-color: var(--c-white);
  border-top: 1px solid var(--c-line);
}

/* --- 相关页面入口 -------------------------------------------------------- */

.related-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}

.related-item {
  padding: 16px 18px;
  background-color: var(--c-white);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  transition: border-color 0.18s ease, transform 0.18s ease;
}

.related-item:hover {
  border-color: var(--c-primary);
  transform: translateY(-2px);
}

.related-item a,
.related-link {
  display: inline-block;
  font-size: 16px;
  font-weight: 600;
  color: var(--c-primary);
}

.related-text,
.related-desc {
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

.related-item span.related-text,
.related-item span.related-desc {
  display: block;
}

/* --- 侧栏通用 ------------------------------------------------------------ */

.side-block,
.aside-block,
.sidebar-nav,
.sidebar-note {
  padding: 16px 18px;
  background-color: var(--c-surface);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

.side-block + .side-block,
.aside-block + .aside-block,
.sidebar-note + .sidebar-note {
  margin-top: 18px;
}

.side-title,
.aside-title,
.sidebar-title {
  font-size: 15px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-text);
  margin-bottom: 10px;
}

.toc-list,
.sidebar-list,
.sidebar-note-list,
.aside-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.toc-link,
.side-link,
.sidebar-list a {
  display: block;
  padding: 6px 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--c-text);
  border-left: 2px solid var(--c-line);
  padding-left: 10px;
  transition: color 0.18s ease, border-color 0.18s ease;
}

.toc-link:hover,
.side-link:hover,
.sidebar-list a:hover {
  color: var(--c-primary);
  border-left-color: var(--c-primary);
}

.toc-link.is-active {
  color: var(--c-primary);
  border-left-color: var(--c-accent);
  font-weight: 600;
}

.side-text,
.aside-text {
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

.aside-item,
.sidebar-note-list li {
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

.aside-item a {
  font-weight: 600;
}

/* --- 页脚 ---------------------------------------------------------------- */

.footer-inner {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) repeat(4, minmax(0, 1fr));
  gap: 32px;
  padding-top: 44px;
  padding-bottom: 32px;
}

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

.footer-name {
  font-size: 18px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-white);
}

.footer-text {
  margin-top: 10px;
  font-size: 14px;
  line-height: 1.7;
  color: #a9b3cc;
}

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

.footer-col-title {
  font-size: 15px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-white);
  margin-bottom: 12px;
}

.footer-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer-list a {
  display: inline-block;
  font-size: 14px;
  line-height: 1.6;
  color: #c3cbe0;
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
}

.footer-copy {
  width: 100%;
  max-width: var(--content-w);
  margin: 0 auto;
  padding: 16px var(--pad-x);
  font-size: 13px;
  line-height: 1.6;
  color: #8d97b3;
}

/* --------------------------------------------------------------------------
   4. pages
   -------------------------------------------------------------------------- */

/* ==== 首页 ================================================================ */

/* --- 时间线首屏 ---------------------------------------------------------- */

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

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 48px;
  align-items: start;
  padding-top: 48px;
  padding-bottom: 48px;
}

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

.hero-eyebrow {
  display: inline-block;
  padding: 4px 12px;
  font-size: 13px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--c-accent);
  background-color: var(--c-white);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-sm);
}

.hero-title {
  margin-top: 16px;
  font-size: 32px;
  font-weight: 700;
  line-height: 1.3;
  color: var(--c-text);
}

.hero-lead {
  margin-top: 14px;
  font-size: 16px;
  line-height: 1.75;
  color: var(--c-text-soft);
  max-width: 46ch;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

.hero-figure {
  margin-top: 26px;
}

/* --- 时间线条目 ---------------------------------------------------------- */

.hero-timeline {
  min-width: 0;
  padding: 22px 24px;
  background-color: var(--c-white);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

.hero-timeline-title {
  font-size: 19px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-text);
  padding-bottom: 12px;
  border-bottom: 1px solid var(--c-line);
}

.timeline-list {
  position: relative;
  margin-top: 6px;
}

.timeline-item {
  position: relative;
  padding: 16px 0 16px 22px;
  border-bottom: 1px dashed var(--c-line);
}

.timeline-item:last-child {
  border-bottom: 0;
  padding-bottom: 4px;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 24px;
  width: 9px;
  height: 9px;
  background-color: var(--c-accent);
  border-radius: 50%;
}

.timeline-date {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.4;
  color: var(--c-text-soft);
}

.timeline-heading {
  margin-top: 4px;
  font-size: 17px;
  font-weight: 600;
  line-height: 1.45;
  color: var(--c-text);
}

.timeline-desc {
  margin-top: 4px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

/* --- 服务方向总览 -------------------------------------------------------- */

.direction-list {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--c-line);
}

.direction-row {
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 18px;
  align-items: start;
  padding: 18px 0;
  border-bottom: 1px solid var(--c-line);
  transition: background-color 0.18s ease;
}

.direction-row:hover {
  background-color: var(--c-surface);
}

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

.direction-name {
  font-size: 19px;
  font-weight: 600;
  line-height: 1.4;
}

.direction-name a {
  color: var(--c-text);
}

.direction-name a:hover {
  color: var(--c-primary);
}

.direction-audience,
.direction-output {
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

.direction-audience::before {
  content: "适用对象：";
  color: var(--c-text);
  font-weight: 600;
}

.direction-output::before {
  content: "典型产出：";
  color: var(--c-text);
  font-weight: 600;
}

.section-figure {
  margin-top: 26px;
}

/* --- 合作流程四阶段预览 -------------------------------------------------- */

.stage-strip {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.stage-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-width: 0;
  padding: 18px;
  background-color: var(--c-white);
  border: 1px solid var(--c-line);
  border-top: 3px solid var(--c-primary);
  border-radius: var(--radius);
  transition: border-color 0.18s ease, transform 0.18s ease;
}

.stage-card:hover {
  border-color: var(--c-primary);
  transform: translateY(-2px);
}

.stage-card .stage-name {
  font-size: 17px;
  font-weight: 600;
  line-height: 1.45;
  color: var(--c-text);
}

.stage-card .stage-actions,
.stage-card .stage-output {
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

.stage-card .stage-actions::before {
  content: "双方动作：";
  color: var(--c-text);
  font-weight: 600;
}

.stage-card .stage-output::before {
  content: "阶段产出物：";
  color: var(--c-text);
  font-weight: 600;
}

/* --- 交付标准与责任边界摘要 ---------------------------------------------- */

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

.standard-col {
  min-width: 0;
  padding: 20px 22px;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

.standard-col-check {
  background-color: var(--c-white);
  border-top: 3px solid var(--c-primary);
}

.standard-col-limit {
  background-color: var(--c-surface);
  border-top: 3px solid var(--c-accent);
}

.standard-col-title {
  font-size: 17px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-text);
  margin-bottom: 12px;
}

.check-list,
.limit-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.check-item,
.limit-item {
  position: relative;
  padding-left: 20px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text);
}

.check-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 9px;
  height: 9px;
  border: 2px solid var(--c-primary);
  border-radius: 2px;
}

.limit-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 9px;
  height: 9px;
  background-color: var(--c-accent);
  border-radius: 2px;
}

.standard-note {
  margin-top: 14px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

.standard-note a {
  font-weight: 600;
}

/* --- 常见需求场景摘要 ---------------------------------------------------- */

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

.scene-group {
  min-width: 0;
  padding: 18px;
  background-color: var(--c-surface);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

.scene-group-title {
  font-size: 16px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-text);
  padding-bottom: 10px;
  margin-bottom: 10px;
  border-bottom: 1px solid var(--c-line);
}

.scene-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.scene-item {
  position: relative;
  padding-left: 16px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

.scene-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 6px;
  height: 6px;
  background-color: var(--c-primary);
  border-radius: 50%;
}

/* --- 站内页面索引 -------------------------------------------------------- */

.index-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 14px;
}

.index-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-width: 0;
  padding: 16px;
  background-color: var(--c-white);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  transition: border-color 0.18s ease, transform 0.18s ease;
}

.index-card:hover {
  border-color: var(--c-primary);
  transform: translateY(-2px);
}

.index-name {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.4;
}

.index-name a {
  color: var(--c-primary);
}

.index-desc {
  font-size: 13px;
  line-height: 1.65;
  color: var(--c-text-soft);
}

/* ==== 服务矩阵 ============================================================ */

.section-matrix {
  margin-top: 0;
}

.matrix-table {
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  overflow: hidden;
}

.matrix-row {
  display: grid;
  grid-template-columns: 1.1fr 1.3fr 1.3fr 1.1fr;
  gap: 0;
  border-bottom: 1px solid var(--c-line);
  background-color: var(--c-white);
}

.matrix-row:last-child {
  border-bottom: 0;
}

.matrix-head {
  background-color: var(--c-surface);
}

.matrix-cell {
  min-width: 0;
  padding: 14px 16px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
  border-right: 1px solid var(--c-line);
}

.matrix-cell:last-child {
  border-right: 0;
}

.matrix-head .matrix-cell {
  font-size: 14px;
  font-weight: 700;
  color: var(--c-text);
}

.matrix-cell.cell-name {
  font-size: 16px;
  font-weight: 600;
  color: var(--c-text);
}

.matrix-cell.cell-exclude {
  color: var(--c-text-soft);
}

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

/* --- 方向分组说明 -------------------------------------------------------- */

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

.group-card {
  min-width: 0;
  padding: 20px 22px;
  background-color: var(--c-surface);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

.group-name {
  margin-top: 10px;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-text);
}

.group-text {
  margin-top: 8px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--c-text-soft);
}

.plain-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-top: 12px;
}

.plain-list li {
  position: relative;
  padding-left: 16px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text);
}

.plain-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 6px;
  height: 6px;
  background-color: var(--c-primary);
  border-radius: 50%;
}

/* --- 方向选择提示 -------------------------------------------------------- */

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

.tip-item {
  min-width: 0;
  padding: 16px 18px;
  background-color: var(--c-white);
  border: 1px solid var(--c-line);
  border-left: 3px solid var(--c-primary);
  border-radius: var(--radius);
}

.tip-name {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.45;
  color: var(--c-text);
}

.tip-text {
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

/* ==== 合作流程 ============================================================ */

.section-stages {
  margin-top: 0;
}

.section-stages .media-figure {
  margin-bottom: 24px;
}

.stage-list {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.stage-item {
  min-width: 0;
  padding: 20px 22px;
  background-color: var(--c-white);
  border: 1px solid var(--c-line);
  border-left: 3px solid var(--c-primary);
  border-radius: var(--radius);
}

.stage-index {
  margin-bottom: 10px;
}

.stage-item .stage-name {
  font-size: 19px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-text);
}

.stage-item .stage-desc {
  margin-top: 8px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--c-text-soft);
}

.stage-cols {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px dashed var(--c-line);
}

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

.stage-col-title {
  font-size: 14px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-primary);
  margin-bottom: 8px;
}

.stage-col ul,
.stage-outputs {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.stage-col li,
.stage-outputs li {
  position: relative;
  padding-left: 16px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text);
}

.stage-col li::before,
.stage-outputs li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 6px;
  height: 6px;
  background-color: var(--c-accent);
  border-radius: 50%;
}

/* --- 阶段进入条件 -------------------------------------------------------- */

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

.entry-item {
  min-width: 0;
  padding: 16px 18px;
  background-color: var(--c-surface);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

.entry-name {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.45;
  color: var(--c-text);
}

.entry-text {
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

/* --- 常见卡点 ------------------------------------------------------------ */

.blocker-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.blocker-item {
  min-width: 0;
  padding: 16px 18px;
  background-color: var(--c-white);
  border: 1px solid var(--c-line);
  border-left: 3px solid var(--c-accent);
  border-radius: var(--radius);
}

.blocker-name {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.45;
  color: var(--c-text);
}

.blocker-text {
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

/* ==== 交付标准 ============================================================ */

.delivery-layout {
  grid-template-columns: minmax(0, 1fr) 300px;
}

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

.content-block + .content-block {
  margin-top: 40px;
}

.content-block .media-figure {
  margin-top: 18px;
}

.checklist {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-top: 20px;
  counter-reset: checklist;
}

.checklist-item {
  counter-increment: checklist;
  min-width: 0;
  padding: 16px 18px 16px 54px;
  position: relative;
  background-color: var(--c-white);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

.checklist-item::before {
  content: counter(checklist, decimal-leading-zero);
  position: absolute;
  left: 16px;
  top: 16px;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  color: var(--c-primary);
}

.checklist-name {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.45;
  color: var(--c-text);
}

.checklist-how,
.checklist-rule {
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

.checklist-how::before {
  content: "核对方式：";
  color: var(--c-text);
  font-weight: 600;
}

.checklist-rule::before {
  content: "判定口径：";
  color: var(--c-text);
  font-weight: 600;
}

.boundary-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin-top: 20px;
}

.boundary-item {
  min-width: 0;
  padding: 16px 18px;
  background-color: var(--c-surface);
  border: 1px solid var(--c-line);
  border-top: 3px solid var(--c-accent);
  border-radius: var(--radius);
}

.boundary-name {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.45;
  color: var(--c-text);
}

.boundary-why {
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

.accept-steps {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-top: 20px;
}

.accept-step {
  position: relative;
  min-width: 0;
  padding: 16px 18px 16px 54px;
  background-color: var(--c-white);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

.accept-step .step-index {
  position: absolute;
  left: 16px;
  top: 16px;
  min-width: 26px;
  height: 24px;
  padding: 0 6px;
}

.accept-step .step-name {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.45;
  color: var(--c-text);
}

.accept-step .step-desc {
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

.delivery-aside .aside-title:not(:first-child) {
  margin-top: 18px;
}

.delivery-aside .aside-list {
  margin-top: 4px;
}

/* ==== 常见问题 ============================================================ */

.faq-index {
  margin-top: 0;
}

.faq-index-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  margin-top: 16px;
}

.faq-index-item {
  min-width: 0;
}

.faq-index-item a {
  display: flex;
  align-items: center;
  min-height: 44px;
  padding: 12px 16px;
  font-size: 15px;
  font-weight: 600;
  color: var(--c-text);
  background-color: var(--c-surface);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  transition: border-color 0.18s ease, color 0.18s ease;
}

.faq-index-item a:hover {
  color: var(--c-primary);
  border-color: var(--c-primary);
}

.faq-group {
  margin-top: 44px;
}

.faq-item {
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  background-color: var(--c-white);
  margin-top: 12px;
  overflow: hidden;
}

.faq-item[open] {
  border-color: var(--c-primary);
}

.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-height: 48px;
  padding: 14px 18px;
  font-size: 16px;
  font-weight: 600;
  line-height: 1.5;
  color: var(--c-text);
  cursor: pointer;
  list-style: none;
  transition: color 0.18s ease, background-color 0.18s ease;
}

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

.faq-question::after {
  content: "+";
  flex: 0 0 auto;
  font-size: 18px;
  font-weight: 700;
  line-height: 1;
  color: var(--c-primary);
}

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

.faq-question:hover {
  color: var(--c-primary);
  background-color: var(--c-surface);
}

.faq-answer {
  padding: 4px 18px 18px;
  border-top: 1px solid var(--c-line);
}

.faq-answer p {
  margin-top: 10px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--c-text-soft);
}

.faq-figure {
  margin-top: 24px;
}

.sidebar-list {
  margin-top: 4px;
}

/* ==== 404 ================================================================ */

.error-main {
  padding-top: 40px;
  padding-bottom: 20px;
}

.error-panel {
  padding: 36px 0 28px;
  border-bottom: 1px solid var(--c-line);
}

.error-code {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  color: var(--c-accent);
}

.error-title {
  margin-top: 10px;
  font-size: 32px;
  font-weight: 700;
  line-height: 1.3;
  color: var(--c-text);
}

.error-text {
  margin-top: 12px;
  font-size: 16px;
  line-height: 1.75;
  color: var(--c-text-soft);
  max-width: 62ch;
}

.error-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

.error-links {
  padding-top: 28px;
}

.error-link-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin-top: 16px;
}

.error-link-list li {
  min-width: 0;
  padding: 16px 18px;
  background-color: var(--c-surface);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

.error-link-list a {
  display: inline-block;
  font-size: 16px;
  font-weight: 600;
  color: var(--c-primary);
}

.error-link-list span {
  display: block;
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-soft);
}

/* --------------------------------------------------------------------------
   5. responsive
   -------------------------------------------------------------------------- */

@media (max-width: 960px) {
  :root {
    --pad-x: 20px;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    margin-left: 0;
    padding: 8px var(--pad-x) 16px;
    background-color: var(--c-white);
    border-bottom: 1px solid var(--c-line);
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    display: none;
  }

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

  .nav-link {
    min-height: 48px;
    padding: 0 12px;
    border-bottom: 1px solid var(--c-line);
  }

  .nav-link.is-current {
    border-bottom-color: var(--c-accent);
  }

  .header-inner {
    position: relative;
    flex-wrap: wrap;
  }

  .hero-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 28px;
    padding-top: 32px;
    padding-bottom: 36px;
  }

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

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

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

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

  .index-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

  .matrix-cell {
    border-right: 0;
    border-bottom: 1px solid var(--c-line);
  }

  .matrix-row .matrix-cell:last-child {
    border-bottom: 0;
  }

  .footer-inner {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 26px;
  }

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

  .page-title,
  .error-title {
    font-size: 27px;
  }

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

@media (max-width: 640px) {
  :root {
    --pad-x: 16px;
  }

  .brand-slogan {
    display: none;
  }

  .hero-title {
    font-size: 24px;
  }

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

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

  .stage-strip,
  .scene-groups,
  .index-grid,
  .group-grid,
  .tip-list,
  .entry-list,
  .boundary-list,
  .faq-index-list,
  .error-link-list {
    grid-template-columns: minmax(0, 1fr);
  }

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

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

  .matrix-head {
    display: none;
  }

  .matrix-cell {
    padding: 10px 14px;
  }

  .matrix-cell.cell-name {
    background-color: var(--c-surface);
  }

  .matrix-cell.cell-target::before {
    content: "适用对象：";
    font-weight: 600;
    color: var(--c-text);
  }

  .matrix-cell.cell-output::before {
    content: "典型产出：";
    font-weight: 600;
    color: var(--c-text);
  }

  .matrix-cell.cell-exclude::before {
    content: "不包含项：";
    font-weight: 600;
    color: var(--c-text);
  }

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

  .checklist-item,
  .accept-step {
    padding-left: 18px;
  }

  .checklist-item::before {
    position: static;
    display: inline-block;
    margin-bottom: 6px;
  }

  .accept-step .step-index {
    position: static;
    margin-bottom: 8px;
  }

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

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

  .btn {
    width: 100%;
  }
}

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

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

  .related-item:hover,
  .stage-card:hover,
  .index-card:hover {
    transform: none;
  }
}