/* ==========================================================================
   樱桃视频 study22.com — 全站样式表
   分组：base / layout / components / pages / responsive
   ========================================================================== */

/* ==========================================================================
   base
   ========================================================================== */

:root {
  --brand: #C4273A;
  --ink: #1E1B1C;
  --paper: #FFFFFF;
  --surface: #F7F4F1;
  --line: #E3DEDA;
  --ok: #1F6B5B;
  --muted: #6B6462;
  --mono: "SFMono-Regular", "Menlo", "Consolas", "Liberation Mono", monospace;
  --radius: 6px;
  --shell: 1080px;
  --read: 720px;
}

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

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

body {
  margin: 0;
  padding: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", sans-serif;
  font-size: 16px;
  line-height: 1.75;
  overflow-wrap: break-word;
}

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

h1 {
  font-size: 32px;
}

h2 {
  font-size: 20px;
  line-height: 1.5;
}

h3 {
  font-size: 17px;
  line-height: 1.5;
}

p {
  margin: 0 0 18px;
}

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

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

dl,
dd,
dt,
figure,
figcaption {
  margin: 0;
}

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

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

a:hover,
a:focus-visible {
  text-decoration: underline;
}

a:focus-visible,
button:focus-visible,
summary:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 2px;
}

button {
  font: inherit;
  color: inherit;
  cursor: pointer;
}

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

th,
td {
  text-align: left;
  vertical-align: top;
}

caption {
  text-align: left;
}

details > summary {
  cursor: pointer;
  list-style: none;
}

details > summary::-webkit-details-marker {
  display: none;
}

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

/* ==========================================================================
   layout — 全站骨架
   ========================================================================== */

.site-body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  background: var(--paper);
  color: var(--ink);
  font-size: 16px;
  line-height: 1.75;
}

.site-main {
  flex: 1 1 auto;
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 24px 72px;
}

.home-main {
  padding-top: 0;
}

.inner-main {
  padding-top: 0;
}

/* 页头 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(255, 255, 255, 0.96);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(6px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 14px 24px;
}

.brand {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
  color: var(--ink);
  text-decoration: none;
}

.brand:hover,
.brand:focus-visible {
  text-decoration: none;
}

.brand-name {
  font-size: 19px;
  font-weight: 600;
  line-height: 1.3;
  color: var(--ink);
}

.brand-tagline {
  font-size: 13px;
  line-height: 1.5;
  color: var(--muted);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 14px;
  flex: 0 0 auto;
}

.menu-toggle {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  min-height: 44px;
  padding: 0 14px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
}

.menu-toggle::before {
  content: "";
  width: 15px;
  height: 10px;
  background-image: linear-gradient(var(--ink), var(--ink)), linear-gradient(var(--ink), var(--ink)), linear-gradient(var(--ink), var(--ink));
  background-repeat: no-repeat;
  background-size: 15px 2px, 11px 2px, 15px 2px;
  background-position: 0 0, 0 4px, 0 8px;
}

.menu-toggle:hover {
  border-color: var(--brand);
  color: var(--brand);
}

.menu-toggle:hover::before {
  background-image: linear-gradient(var(--brand), var(--brand)), linear-gradient(var(--brand), var(--brand)), linear-gradient(var(--brand), var(--brand));
}

.header-cta {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 18px;
  background: var(--brand);
  border: 1px solid var(--brand);
  border-radius: var(--radius);
  color: #FFFFFF;
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
}

.header-cta:hover,
.header-cta:focus-visible {
  background: #A81E30;
  border-color: #A81E30;
  color: #FFFFFF;
  text-decoration: none;
}

.header-cta.is-current {
  background: var(--surface);
  border-color: var(--line);
  color: var(--ink);
}

.header-cta.is-current:hover {
  border-color: var(--brand);
  color: var(--brand);
}

/* 全屏目录索引 */
.site-index {
  position: fixed;
  inset: 0;
  z-index: 60;
  overflow-y: auto;
  padding: 96px 24px 64px;
  background: var(--paper);
}

.site-index[hidden] {
  display: none;
}

.index-group {
  max-width: var(--shell);
  margin: 0 auto 34px;
  padding-bottom: 26px;
  border-bottom: 1px solid var(--line);
}

.index-group:last-of-type {
  border-bottom: 0;
}

.index-group-title {
  margin-bottom: 14px;
  font-size: 13px;
  font-weight: 600;
  color: var(--muted);
}

.index-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 10px;
}

.index-list li {
  min-width: 0;
}

.index-list a {
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-height: 48px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--ink);
  text-decoration: none;
}

.index-list a:hover,
.index-list a:focus-visible {
  border-color: var(--brand);
  background: var(--surface);
  text-decoration: none;
}

.index-note {
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

/* 面包屑 */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 22px 24px 0;
  font-size: 13px;
  color: var(--muted);
}

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

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

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

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

/* 页面标题区 */
.page-header {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 16px 24px 0;
}

.page-title {
  font-size: 32px;
  font-weight: 600;
  line-height: 1.35;
  color: var(--ink);
}

/* 页脚 */
.site-footer {
  margin-top: 40px;
  background: var(--surface);
  border-top: 1px solid var(--line);
  font-size: 15px;
  color: var(--ink);
}

.footer-inner {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.1fr;
  gap: 32px;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 44px 24px 32px;
}

.footer-brand-name {
  margin-bottom: 10px;
  font-size: 18px;
  font-weight: 600;
  color: var(--ink);
}

.footer-brand-line {
  margin-bottom: 12px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink);
}

.footer-note {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

.footer-col h3 {
  margin-bottom: 12px;
  font-size: 13px;
  font-weight: 600;
  color: var(--muted);
}

.footer-col ul {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.footer-col a {
  display: inline-block;
  padding: 5px 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--ink);
}

.footer-col a:hover,
.footer-col a:focus-visible {
  color: var(--brand);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 18px 24px 28px;
  border-top: 1px solid var(--line);
}

.footer-copyright {
  margin: 0;
  font-size: 13px;
  color: var(--muted);
}

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

.footer-bottom-links a {
  font-size: 13px;
  color: var(--muted);
}

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

/* ==========================================================================
   components — 通用模块
   ========================================================================== */

.section {
  padding: 44px 0;
  border-bottom: 1px solid var(--line);
}

.section:last-child {
  border-bottom: 0;
}

.section > h2,
.section-head > h2 {
  margin-bottom: 8px;
}

.section-lead,
.section-intro {
  max-width: var(--read);
  margin-bottom: 22px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--muted);
}

.section-note,
.table-note,
.scope-note,
.page-note {
  margin-top: 14px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

.page-summary {
  max-width: var(--read);
  margin-bottom: 10px;
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink);
}

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

.page-hero-inner {
  max-width: var(--read);
}

.page-lead {
  max-width: var(--read);
  margin-bottom: 10px;
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink);
}

.section-head {
  margin-bottom: 20px;
}

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

.compare-table,
.data-table {
  min-width: 640px;
  font-size: 15px;
  line-height: 1.7;
}

.compare-table caption,
.data-table caption {
  padding: 12px 16px;
  font-size: 13px;
  color: var(--muted);
}

.compare-table thead th,
.data-table thead th {
  padding: 12px 16px;
  background: #F1ECE8;
  border-bottom: 1px solid var(--line);
  font-size: 13px;
  font-weight: 600;
  color: var(--muted);
  white-space: nowrap;
}

.compare-table tbody th,
.data-table tbody th {
  padding: 14px 16px;
  border-bottom: 1px solid var(--line);
  border-right: 1px solid var(--line);
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
  white-space: nowrap;
}

.compare-table tbody td,
.data-table tbody td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--line);
  color: var(--ink);
}

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

.compare-table tbody tr:hover th,
.compare-table tbody tr:hover td,
.data-table tbody tr:hover th,
.data-table tbody tr:hover td {
  background: #FBF8F5;
}

/* 勾选清单 */
.check-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.check-list .check-item {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding-left: 22px;
  position: relative;
  font-size: 15px;
  line-height: 1.7;
}

.check-list .check-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 10px;
  height: 10px;
  border: 1px solid var(--line);
  border-radius: 2px;
  background: var(--paper);
}

.check-list .check-label {
  font-weight: 600;
  color: var(--ink);
}

.check-list .check-desc {
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

/* 文字入口链接 */
.text-link {
  display: inline-block;
  margin-top: 20px;
  padding-bottom: 2px;
  border-bottom: 1px solid var(--brand);
  font-size: 15px;
  font-weight: 600;
  color: var(--brand);
}

.text-link:hover,
.text-link:focus-visible {
  color: #A81E30;
  border-bottom-color: #A81E30;
  text-decoration: none;
}

/* 相关入口列表 */
.related-links {
  padding: 40px 0 0;
}

.related-links h2 {
  margin-bottom: 16px;
}

.related-links ul,
.related-list,
.related-entry-list,
.link-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 10px;
}

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

.related-links a,
.related-list a,
.related-entry-list a,
.link-list a {
  display: flex;
  flex-direction: column;
  gap: 3px;
  min-height: 48px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--ink);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
}

.related-links a:hover,
.related-list a:hover,
.related-entry-list a:hover,
.link-list a:hover,
.related-links a:focus-visible,
.related-list a:focus-visible,
.related-entry-list a:focus-visible,
.link-list a:focus-visible {
  border-color: var(--brand);
  background: var(--paper);
  text-decoration: none;
}

.related-desc {
  font-size: 13px;
  font-weight: 400;
  line-height: 1.7;
  color: var(--muted);
}

/* 通用图片容器 */
.media-figure,
.section-media,
.scene-figure,
.issue-figure,
.roles-figure,
.review-method-figure {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.media-figure img,
.section-media img,
.scene-figure img,
.issue-figure img,
.roles-figure img,
.review-method-figure img {
  width: 100%;
  height: auto;
  object-fit: cover;
}

.media-figure figcaption,
.section-media figcaption,
.scene-figure figcaption,
.issue-figure figcaption,
.roles-figure figcaption,
.review-method-figure figcaption {
  padding: 12px 16px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

/* 折叠问答 */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

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

.faq-item summary {
  position: relative;
  padding: 14px 44px 14px 16px;
  font-size: 16px;
  font-weight: 600;
  line-height: 1.6;
  color: var(--ink);
}

.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 16px;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--mono);
  font-size: 18px;
  color: var(--brand);
}

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

.faq-item[open] summary {
  border-bottom: 1px solid var(--line);
}

.faq-item p {
  padding: 14px 16px;
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink);
}

/* 结论摘要条 */
.conclusion-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.conclusion-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--ok);
  border-radius: var(--radius);
  background: var(--surface);
}

.conclusion-mark {
  flex: 0 0 auto;
  padding-top: 2px;
  font-family: var(--mono);
  font-size: 13px;
  color: var(--ok);
}

.conclusion-item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink);
}

/* 锚点条 */
.anchor-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 0 0 4px;
  margin-bottom: 8px;
}

.anchor-bar a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  font-size: 14px;
  font-weight: 600;
  color: var(--ink);
  text-decoration: none;
}

.anchor-bar a:hover,
.anchor-bar a:focus-visible {
  border-color: var(--brand);
  color: var(--brand);
  text-decoration: none;
}

/* ==========================================================================
   pages — 首页
   ========================================================================== */

/* 首屏 */
.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: 40px;
  align-items: start;
  padding: 48px 0 44px;
  border-bottom: 1px solid var(--line);
}

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

.hero-content h1 {
  margin-bottom: 14px;
  font-size: 32px;
  line-height: 1.35;
}

.hero-lead {
  max-width: 520px;
  margin-bottom: 26px;
  font-size: 16px;
  line-height: 1.75;
  color: var(--muted);
}

.service-index {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--line);
  margin-bottom: 26px;
}

.service-index-item {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr) minmax(0, 1.15fr) auto;
  gap: 12px;
  align-items: baseline;
  padding: 12px 4px;
  border-bottom: 1px solid var(--line);
}

.service-index-item:hover {
  background: var(--surface);
}

.index-num {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--brand);
}

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

.index-goal {
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.index-cycle {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--ink);
  white-space: nowrap;
}

.hero-cta {
  display: inline-flex;
  align-items: center;
  min-height: 46px;
  padding: 0 22px;
  background: var(--brand);
  border: 1px solid var(--brand);
  border-radius: var(--radius);
  color: #FFFFFF;
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
}

.hero-cta:hover,
.hero-cta:focus-visible {
  background: #A81E30;
  border-color: #A81E30;
  color: #FFFFFF;
  text-decoration: none;
}

.hero-media {
  display: grid;
  grid-template-columns: minmax(0, 2fr) minmax(0, 1fr);
  gap: 12px;
  min-width: 0;
}

.hero-figure,
.hero-thumb {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.hero-figure img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.hero-thumb img {
  width: 100%;
  aspect-ratio: 3 / 4;
  object-fit: cover;
}

.hero-figure figcaption,
.hero-thumb figcaption {
  padding: 10px 12px;
  border-top: 1px solid var(--line);
  font-size: 12px;
  line-height: 1.6;
  color: var(--muted);
}

/* 制作阶段时间线 */
.stage-timeline {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 0;
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}

.stage-item {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 16px 14px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--paper);
}

.stage-item:hover {
  background: var(--surface);
}

.stage-num {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--brand);
}

.stage-item h3 {
  font-size: 16px;
  font-weight: 600;
}

.stage-detail {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 4px 8px;
  font-size: 13px;
  line-height: 1.65;
}

.stage-detail dt {
  color: var(--muted);
  white-space: nowrap;
}

.stage-detail dd {
  color: var(--ink);
}

/* 素材清单预览 */
.material-columns {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.material-column {
  min-width: 0;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.material-column h3 {
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  font-size: 16px;
}

/* 场景示例索引 */
.scenario-index {
  display: flex;
  flex-direction: column;
  max-width: 820px;
  margin: 0 auto;
  border-top: 1px solid var(--line);
}

.scenario-item {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding: 15px 6px;
  border-bottom: 1px solid var(--line);
}

.scenario-item:hover {
  background: var(--surface);
}

.scenario-num {
  padding-top: 3px;
  font-family: var(--mono);
  font-size: 13px;
  color: var(--brand);
}

.scenario-body h3 {
  margin-bottom: 4px;
  font-size: 16px;
}

.scenario-body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* 更新记录摘要 */
.changelog-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.changelog-item {
  display: grid;
  grid-template-columns: 128px minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.changelog-tag {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--brand);
}

.changelog-item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink);
}

/* ==========================================================================
   pages — 服务目录
   ========================================================================== */

.section-services-table {
  padding-top: 40px;
}

.section-service-detail .service-block {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
  gap: 28px;
  align-items: start;
  padding: 26px 0;
  border-top: 1px solid var(--line);
}

.section-service-detail .service-block:last-child {
  border-bottom: 1px solid var(--line);
}

.service-block-text {
  min-width: 0;
}

.service-block-text h3 {
  margin-bottom: 14px;
  font-size: 19px;
}

.service-fields {
  display: grid;
  grid-template-columns: 96px minmax(0, 1fr);
  gap: 8px 16px;
  font-size: 15px;
  line-height: 1.7;
}

.service-fields dt {
  color: var(--muted);
  font-size: 14px;
}

.service-fields dd {
  color: var(--ink);
}

.service-block-media {
  min-width: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.service-block-media img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.service-block-media figcaption {
  padding: 10px 14px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

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

.stage-map-item {
  display: grid;
  grid-template-columns: 200px minmax(0, 1fr);
  gap: 16px;
  align-items: baseline;
  padding: 14px 4px;
  border-bottom: 1px solid var(--line);
}

.stage-map-item:hover {
  background: var(--surface);
}

.stage-map-name {
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
}

.stage-map-item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* ==========================================================================
   pages — 合作启动
   ========================================================================== */

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

.prereq-item {
  position: relative;
  padding: 18px 18px 18px 54px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.prereq-index {
  position: absolute;
  left: 18px;
  top: 19px;
  font-family: var(--mono);
  font-size: 15px;
  color: var(--brand);
}

.prereq-item h3 {
  margin-bottom: 6px;
  font-size: 16px;
}

.prereq-item p {
  margin-bottom: 8px;
  font-size: 15px;
  line-height: 1.75;
}

.prereq-consequence {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

#requirement-checklist .check-list {
  max-width: var(--read);
}

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

.asset-col {
  min-width: 0;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.asset-col h3 {
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  font-size: 16px;
}

.check-list.compact .check-item {
  padding-left: 20px;
  font-size: 14px;
}

.check-list.compact .check-item::before {
  top: 8px;
  width: 9px;
  height: 9px;
}

#prep-scene {
  padding: 34px 0;
}

#prep-scene .media-figure img {
  aspect-ratio: 16 / 7;
  object-fit: cover;
}

.step-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 16px;
}

.step-item {
  min-width: 0;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
}

.step-item:hover {
  background: var(--surface);
}

.step-index {
  display: block;
  margin-bottom: 8px;
  font-family: var(--mono);
  font-size: 13px;
  color: var(--brand);
}

.step-item h3 {
  margin-bottom: 6px;
  font-size: 16px;
}

.step-item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.condition-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  max-width: var(--read);
}

.condition-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 16px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--ok);
  border-radius: var(--radius);
  background: var(--surface);
}

.condition-mark {
  flex: 0 0 auto;
  padding-top: 3px;
  font-family: var(--mono);
  font-size: 13px;
  color: var(--ok);
}

.condition-body h3 {
  margin-bottom: 4px;
  font-size: 16px;
}

.condition-body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* ==========================================================================
   pages — 场景示例
   ========================================================================== */

.scene-group {
  padding: 40px 0;
  border-bottom: 1px solid var(--line);
  scroll-margin-top: 92px;
}

.scene-group-head {
  display: grid;
  grid-template-columns: 48px minmax(0, 1fr);
  gap: 6px 14px;
  align-items: baseline;
  margin-bottom: 22px;
}

.scene-group-no {
  grid-row: span 2;
  font-family: var(--mono);
  font-size: 14px;
  color: var(--brand);
}

.scene-group-head h2 {
  font-size: 21px;
}

.scene-group-desc {
  grid-column: 2;
  margin: 0;
  max-width: var(--read);
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.scene-figure {
  margin-bottom: 22px;
}

.scene-figure img {
  aspect-ratio: 16 / 7;
  object-fit: cover;
}

.scene-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 18px;
  max-width: 820px;
  margin: 0 auto;
}

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

.scene-item h3 {
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  font-size: 16px;
}

.scene-fields {
  display: grid;
  grid-template-columns: 84px minmax(0, 1fr);
  gap: 6px 12px;
  font-size: 14px;
  line-height: 1.7;
}

.scene-fields dt {
  color: var(--muted);
}

.scene-fields dd {
  color: var(--ink);
}

.scene-note {
  margin: 12px 0 0;
  padding-top: 10px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

.team-roles {
  padding: 40px 0;
  border-bottom: 1px solid var(--line);
}

.team-roles h2 {
  margin-bottom: 20px;
}

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

.roles-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.roles-list li {
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink);
}

.roles-list strong {
  display: block;
  margin-bottom: 4px;
  font-size: 16px;
  color: var(--ink);
}

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

.roles-figure img {
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

/* ==========================================================================
   pages — 交付与验收
   ========================================================================== */

.checklist {
  display: flex;
  flex-direction: column;
  max-width: var(--read);
  border-top: 1px solid var(--line);
}

.checklist-item {
  display: grid;
  grid-template-columns: 168px minmax(0, 1fr);
  gap: 16px;
  align-items: baseline;
  padding: 13px 4px;
  border-bottom: 1px solid var(--line);
}

.checklist-item:hover {
  background: var(--surface);
}

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

.checklist-desc {
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.revision .compare-table {
  max-width: var(--read);
}

.acceptance .section-media {
  margin-bottom: 22px;
}

.acceptance .section-media img {
  aspect-ratio: 16 / 7;
  object-fit: cover;
}

.acceptance-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 12px;
  max-width: var(--read);
}

.acceptance-item {
  display: flex;
  flex-direction: column;
  gap: 3px;
  padding: 13px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

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

.acceptance-desc {
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

.archive-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  max-width: var(--read);
}

.archive-item {
  display: flex;
  flex-direction: column;
  gap: 3px;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--ok);
  border-radius: var(--radius);
  background: var(--surface);
}

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

.archive-desc {
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* ==========================================================================
   pages — 更新记录
   ========================================================================== */

.spec-categories {
  padding: 34px 0;
  border-bottom: 1px solid var(--line);
}

.spec-categories h2 {
  margin-bottom: 8px;
}

.spec-category-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin-top: 20px;
}

.spec-category {
  min-width: 0;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.spec-category h3 {
  margin-bottom: 8px;
  font-size: 16px;
}

.spec-category p {
  margin-bottom: 10px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.spec-category-link {
  margin: 0;
}

.spec-category-link a {
  font-size: 14px;
  font-weight: 600;
}

.changelog-list {
  padding: 34px 0;
  border-bottom: 1px solid var(--line);
}

.changelog-list h2 {
  margin-bottom: 8px;
}

.changelog-entries {
  display: flex;
  flex-direction: column;
  margin-top: 20px;
  border-top: 1px solid var(--line);
}

.changelog-entries .changelog-item {
  display: block;
  padding: 20px 4px;
  border: 0;
  border-bottom: 1px solid var(--line);
  border-radius: 0;
  background: transparent;
}

.changelog-entries .changelog-item:hover {
  background: var(--surface);
}

.changelog-entries .changelog-tag {
  display: inline-block;
  margin-bottom: 8px;
  padding: 2px 8px;
  border: 1px solid var(--line);
  border-radius: 3px;
  background: var(--surface);
  font-family: var(--mono);
  font-size: 12px;
  color: var(--brand);
}

.changelog-entries h3 {
  margin-bottom: 12px;
  font-size: 17px;
}

.changelog-fields {
  display: grid;
  grid-template-columns: 84px minmax(0, 1fr);
  gap: 8px 16px;
  font-size: 15px;
  line-height: 1.7;
}

.changelog-fields dt {
  color: var(--muted);
  font-size: 14px;
}

.changelog-fields dd {
  color: var(--ink);
}

.review-method {
  padding: 34px 0;
  border-bottom: 1px solid var(--line);
}

.review-method h2 {
  margin-bottom: 8px;
}

.review-method-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 28px;
  align-items: start;
  margin-top: 20px;
}

.review-method-text {
  min-width: 0;
}

.review-steps {
  display: flex;
  flex-direction: column;
  gap: 12px;
  counter-reset: review-step;
}

.review-steps li {
  position: relative;
  padding-left: 34px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink);
}

.review-steps li::before {
  counter-increment: review-step;
  content: counter(review-step, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 2px;
  font-family: var(--mono);
  font-size: 13px;
  color: var(--brand);
}

.review-method-text .page-note {
  margin-top: 16px;
}

.review-method-figure {
  min-width: 0;
}

.review-method-figure img {
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

/* ==========================================================================
   pages — 问题排查
   ========================================================================== */

.issue-list {
  padding: 8px 0 0;
}

.issue-group {
  padding: 34px 0;
  border-bottom: 1px solid var(--line);
  scroll-margin-top: 92px;
}

.issue-group h2 {
  margin-bottom: 18px;
  font-size: 20px;
}

.issue-figure {
  margin-bottom: 20px;
}

.issue-figure img {
  aspect-ratio: 16 / 7;
  object-fit: cover;
}

.issue-item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

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

.issue-item summary {
  position: relative;
  padding: 15px 44px 15px 16px;
  font-size: 16px;
  font-weight: 600;
  line-height: 1.6;
  color: var(--ink);
}

.issue-item summary::after {
  content: "+";
  position: absolute;
  right: 16px;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--mono);
  font-size: 18px;
  color: var(--brand);
}

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

.issue-item[open] summary {
  border-bottom: 1px solid var(--line);
}

.issue-body {
  padding: 16px;
}

.issue-conclusion {
  margin: 0 0 12px;
  padding-left: 14px;
  border-left: 3px solid var(--ok);
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink);
}

.issue-body p {
  margin-bottom: 10px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}

.issue-body p:last-child {
  margin-bottom: 0;
}

.issue-body strong {
  color: var(--ink);
}

.rollback-section {
  padding: 34px 0;
  border-bottom: 1px solid var(--line);
}

.rollback-section h2 {
  margin-bottom: 8px;
}

.rollback-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
  margin-top: 20px;
}

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

.rollback-list h3 {
  margin-bottom: 6px;
  font-size: 16px;
}

.rollback-list p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* ==========================================================================
   pages — 404
   ========================================================================== */

.error-main {
  display: flex;
  align-items: flex-start;
  justify-content: center;
}

.error-block {
  width: 100%;
  max-width: 640px;
  padding: 72px 0 40px;
}

.error-block h1 {
  margin-bottom: 14px;
  font-size: 30px;
}

.error-lead {
  margin-bottom: 10px;
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink);
}

.error-note {
  margin-bottom: 26px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}

.error-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 30px;
}

.button-primary,
.button-secondary {
  display: inline-flex;
  align-items: center;
  min-height: 46px;
  padding: 0 22px;
  border-radius: var(--radius);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
}

.button-primary {
  background: var(--brand);
  border: 1px solid var(--brand);
  color: #FFFFFF;
}

.button-primary:hover,
.button-primary:focus-visible {
  background: #A81E30;
  border-color: #A81E30;
  color: #FFFFFF;
  text-decoration: none;
}

.button-secondary {
  background: var(--surface);
  border: 1px solid var(--line);
  color: var(--ink);
}

.button-secondary:hover,
.button-secondary:focus-visible {
  border-color: var(--brand);
  color: var(--brand);
  text-decoration: none;
}

.error-links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 10px;
}

.error-links a {
  display: flex;
  align-items: center;
  min-height: 48px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
  text-decoration: none;
}

.error-links a:hover,
.error-links a:focus-visible {
  border-color: var(--brand);
  color: var(--brand);
  text-decoration: none;
}

/* ==========================================================================
   responsive
   ========================================================================== */

@media (max-width: 1024px) {
  h1,
  .page-title,
  .hero-content h1 {
    font-size: 28px;
  }

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

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

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

  .material-columns,
  .asset-columns,
  .spec-category-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .footer-inner {
    grid-template-columns: 1.3fr 1fr 1fr;
    gap: 26px;
  }

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

  .section-service-detail .service-block,
  .roles-body,
  .review-method-body {
    grid-template-columns: minmax(0, 1fr);
    gap: 20px;
  }

  .service-block-media,
  .roles-figure,
  .review-method-figure {
    max-width: 560px;
  }
}

@media (max-width: 768px) {
  .site-main {
    padding: 0 18px 56px;
  }

  .header-inner,
  .breadcrumb,
  .page-header,
  .page-hero,
  .footer-inner,
  .footer-bottom {
    padding-left: 18px;
    padding-right: 18px;
  }

  .header-inner {
    flex-wrap: wrap;
    gap: 12px;
  }

  .brand-tagline {
    font-size: 12px;
  }

  .site-index {
    padding: 88px 18px 56px;
  }

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

  .section {
    padding: 34px 0;
  }

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

  .material-columns,
  .asset-columns,
  .spec-category-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .service-index-item {
    grid-template-columns: 30px minmax(0, 1fr);
    row-gap: 4px;
  }

  .index-goal {
    grid-column: 2;
  }

  .index-cycle {
    grid-column: 2;
  }

  .changelog-item {
    grid-template-columns: minmax(0, 1fr);
    gap: 6px;
  }

  .checklist-item,
  .stage-map-item,
  .service-fields,
  .scene-fields,
  .changelog-fields {
    grid-template-columns: minmax(0, 1fr);
    gap: 4px;
  }

  .checklist-item,
  .stage-map-item {
    row-gap: 3px;
  }

  .service-fields dt,
  .scene-fields dt,
  .changelog-fields dt {
    padding-top: 4px;
  }

  .footer-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
    padding-top: 34px;
  }

  .footer-brand {
    grid-column: auto;
  }

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

  .scene-group-head {
    grid-template-columns: 38px minmax(0, 1fr);
  }

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

  .error-block {
    padding: 48px 0 32px;
  }
}

@media (max-width: 480px) {
  h1,
  .page-title,
  .hero-content h1 {
    font-size: 24px;
  }

  h2,
  .scene-group-head h2,
  .issue-group h2 {
    font-size: 19px;
  }

  .header-actions {
    gap: 10px;
  }

  .menu-toggle,
  .header-cta {
    padding: 0 12px;
    font-size: 14px;
  }

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

  .hero-thumb img {
    aspect-ratio: 16 / 9;
  }

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

  .scenario-item {
    grid-template-columns: 32px minmax(0, 1fr);
    gap: 10px;
  }

  .prereq-item {
    padding: 16px 16px 16px 46px;
  }

  .prereq-index {
    left: 16px;
    top: 17px;
  }

  .step-list,
  .acceptance-list,
  .rollback-list,
  .related-links ul,
  .related-list,
  .related-entry-list,
  .link-list,
  .error-links {
    grid-template-columns: minmax(0, 1fr);
  }

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

  .button-primary,
  .button-secondary {
    justify-content: center;
  }
}