:root {
  --ink: #141414;
  --ink-soft: #4a4a4a;
  --rule: #d8d8d8;
  --rule-strong: #b4b4b4;
  --paper: #fbfbf9;
  --paper-alt: #f3f2ee;
  --accent: #7a1f1f;
  --accent-soft: #a84848;
  --serif: "Songti SC", "SimSun", "Source Han Serif SC", "Noto Serif SC", Georgia, serif;
  --sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Helvetica Neue", Arial, sans-serif;
  --wrap: 1120px;
  --gap: 40px;
}

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

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

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

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

body.site-body p {
  margin: 0 0 16px;
  color: var(--ink-soft);
}

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

h1,
h2,
h3,
h4 {
  margin: 0;
  font-family: var(--serif);
  color: var(--ink);
  font-weight: 700;
  line-height: 1.35;
}

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

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

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

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

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

figure {
  margin: 0;
}

table {
  border-collapse: collapse;
  border-spacing: 0;
}

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

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

.header-inner {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 18px 24px 14px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 32px;
}

.brand {
  font-family: var(--serif);
  font-size: 22px;
  font-weight: 700;
  color: var(--ink);
  letter-spacing: normal;
  white-space: nowrap;
}

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

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

.nav-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px 26px;
}

.nav-link {
  display: inline-block;
  padding: 6px 0;
  font-size: 15px;
  color: var(--ink);
  border-bottom: 2px solid transparent;
}

.nav-link:hover,
.nav-link:focus-visible {
  color: var(--accent);
  text-decoration: none;
  border-bottom-color: var(--rule-strong);
}

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

.nav-toggle {
  display: none;
  margin-left: auto;
  width: 44px;
  height: 44px;
  padding: 0;
  background-color: transparent;
  border: 1px solid var(--rule);
  border-radius: 4px;
  cursor: pointer;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
}

.nav-toggle-bar {
  display: block;
  width: 20px;
  height: 2px;
  background-color: var(--ink);
}

.subnav {
  border-top: 1px solid var(--rule);
  background-color: var(--paper-alt);
}

.subnav-list {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 10px 24px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 24px;
}

.subnav-link {
  display: inline-block;
  padding: 3px 0;
  font-size: 14px;
  color: var(--ink-soft);
  border-bottom: 1px solid transparent;
}

.subnav-link:hover,
.subnav-link:focus-visible {
  color: var(--accent);
  text-decoration: none;
  border-bottom-color: var(--accent-soft);
}

.site-main {
  display: block;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 24px 64px;
}

.inner-main {
  padding-top: 26px;
}

/* ============================================================
   components — 通用元件
   ============================================================ */

.section-head {
  margin-bottom: 22px;
  padding-bottom: 14px;
  border-bottom: 2px solid var(--ink);
}

.section-title {
  font-size: 24px;
  margin-bottom: 8px;
}

.section-desc,
.section-note,
.section-intro {
  font-size: 15px;
  color: var(--ink-soft);
  max-width: 760px;
}

.section-note,
.section-intro {
  margin-bottom: 20px;
}

.section-more {
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px solid var(--rule);
  font-size: 15px;
}

.text-link {
  color: var(--accent);
  font-weight: 600;
  border-bottom: 1px solid var(--accent-soft);
  padding-bottom: 1px;
}

.text-link:hover,
.text-link:focus-visible {
  text-decoration: none;
  color: var(--ink);
  border-bottom-color: var(--ink);
}

.btn {
  display: inline-block;
  min-height: 44px;
  padding: 10px 22px;
  font-size: 15px;
  font-weight: 600;
  border-radius: 4px;
  border: 1px solid var(--ink);
  transition: background-color 0.18s ease, color 0.18s ease, border-color 0.18s ease;
}

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

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

.btn-primary:hover,
.btn-primary:focus-visible {
  background-color: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

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

.btn-ghost:hover,
.btn-ghost:focus-visible {
  background-color: var(--paper-alt);
  border-color: var(--accent);
  color: var(--accent);
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-bottom: 14px;
  margin-bottom: 22px;
  border-bottom: 1px solid var(--rule);
  font-size: 14px;
  color: var(--ink-soft);
}

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

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

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

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

.page-header {
  margin-bottom: 34px;
  padding-bottom: 22px;
  border-bottom: 1px solid var(--rule);
}

.page-title {
  font-size: 34px;
  line-height: 1.3;
  margin-bottom: 12px;
}

.page-description {
  font-size: 16px;
  color: var(--ink-soft);
  max-width: 760px;
}

.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 260px;
  gap: var(--gap);
  align-items: start;
}

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

.layout-aside,
.sidebar {
  min-width: 0;
  border-top: 2px solid var(--ink);
  padding-top: 16px;
}

.aside-block,
.sidebar-block {
  margin-bottom: 28px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--rule);
}

.aside-block:last-child,
.sidebar-block:last-child {
  margin-bottom: 0;
  padding-bottom: 0;
  border-bottom: 0;
}

.aside-title,
.sidebar-title {
  font-size: 16px;
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rule);
}

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

.aside-item,
.aside-link-item,
.sidebar-item {
  font-size: 14px;
  line-height: 1.6;
  color: var(--ink-soft);
}

.aside-link,
.sidebar-link,
.stage-index-link {
  color: var(--ink-soft);
  border-bottom: 1px solid transparent;
}

.aside-link:hover,
.aside-link:focus-visible,
.sidebar-link:hover,
.sidebar-link:focus-visible,
.stage-index-link:hover,
.stage-index-link:focus-visible {
  color: var(--accent);
  text-decoration: none;
  border-bottom-color: var(--accent-soft);
}

.aside-text,
.aside-note {
  font-size: 14px;
  color: var(--ink-soft);
  margin-bottom: 12px;
}

.aside-list-plain {
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 14px;
  color: var(--ink-soft);
}

.aside-list-plain li {
  padding-left: 14px;
  position: relative;
}

.aside-list-plain li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--rule-strong);
}

/* 表格 */

.table-scroll {
  overflow-x: auto;
  border: 1px solid var(--rule);
  border-radius: 4px;
  background-color: #fff;
}

.data-table {
  width: 100%;
  min-width: 560px;
  font-size: 15px;
  text-align: left;
}

.table-caption {
  caption-side: top;
  padding: 12px 16px;
  text-align: left;
  font-size: 14px;
  color: var(--ink-soft);
  border-bottom: 1px solid var(--rule);
  background-color: var(--paper-alt);
}

.data-table thead th {
  padding: 12px 16px;
  font-family: var(--serif);
  font-size: 15px;
  color: var(--ink);
  background-color: var(--paper-alt);
  border-bottom: 2px solid var(--ink);
  white-space: nowrap;
}

.data-table tbody th,
.data-table tbody td {
  padding: 12px 16px;
  vertical-align: top;
  border-bottom: 1px solid var(--rule);
  color: var(--ink-soft);
}

.data-table tbody th {
  font-weight: 700;
  color: var(--ink);
  white-space: nowrap;
}

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

.data-table tbody tr:hover {
  background-color: #f7f6f2;
}

/* FAQ 折叠 */

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 0;
  border-top: 1px solid var(--rule);
}

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

.faq-question {
  position: relative;
  padding: 16px 40px 16px 0;
  font-family: var(--serif);
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
  cursor: pointer;
  list-style: none;
}

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

.faq-question::after {
  content: "+";
  position: absolute;
  right: 6px;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--sans);
  font-size: 20px;
  color: var(--accent);
  line-height: 1;
}

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

.faq-question:hover {
  color: var(--accent);
}

.faq-answer {
  padding: 0 0 18px;
  max-width: 720px;
  font-size: 15px;
}

.faq-answer p {
  margin-bottom: 12px;
}

.faq-link,
.faq-jump {
  font-size: 14px;
}

/* 图片容器 */

.hero-figure,
.content-media,
.direction-media,
.media-figure,
.section-figure,
.page-figure {
  overflow: hidden;
  border: 1px solid var(--rule);
  border-radius: 4px;
  background-color: var(--paper-alt);
}

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

.hero-caption,
.hero-figure figcaption,
.content-media figcaption,
.direction-caption,
.media-caption,
.figure-caption {
  padding: 10px 14px;
  font-size: 13px;
  color: var(--ink-soft);
  border-top: 1px solid var(--rule);
  background-color: var(--paper-alt);
}

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

.hero-section {
  padding: 40px 0 44px;
  border-bottom: 1px solid var(--rule);
}

.hero-layout {
  display: grid;
  grid-template-columns: 240px minmax(0, 1fr);
  gap: var(--gap);
  align-items: start;
}

.hero-index {
  border-top: 2px solid var(--ink);
  padding-top: 14px;
}

.hero-index-title {
  font-size: 15px;
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rule);
  color: var(--ink);
}

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

.hero-index-item {
  font-size: 14px;
  line-height: 1.6;
}

.hero-index-link {
  display: inline-block;
  font-family: var(--serif);
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
  border-bottom: 1px solid transparent;
}

.hero-index-link:hover,
.hero-index-link:focus-visible {
  color: var(--accent);
  border-bottom-color: var(--accent);
  text-decoration: none;
}

.hero-index-note {
  margin: 4px 0 0;
  font-size: 13px;
  color: var(--ink-soft);
}

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

.hero-title {
  font-size: 34px;
  line-height: 1.32;
  margin-bottom: 14px;
}

.hero-lead {
  font-size: 16px;
  color: var(--ink-soft);
  max-width: 640px;
  margin-bottom: 22px;
}

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

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

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.content-media-primary {
  margin-top: 34px;
}

.content-media-primary img {
  aspect-ratio: 21 / 9;
}

.directions-section,
.process-section,
.standards-section,
.faq-section,
.entry-section {
  padding: 44px 0;
  border-bottom: 1px solid var(--rule);
}

.entry-section {
  border-bottom: 0;
  padding-bottom: 20px;
}

.directions-list {
  border-top: 1px solid var(--rule);
}

.direction-row {
  display: grid;
  grid-template-columns: minmax(140px, 1fr) minmax(0, 1.1fr) minmax(0, 1.1fr) minmax(0, 1.1fr);
  gap: 20px;
  padding: 20px 0;
  border-bottom: 1px solid var(--rule);
}

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

.direction-name {
  font-size: 18px;
  margin-bottom: 4px;
}

.direction-label {
  margin: 0 0 4px;
  font-size: 13px;
  color: var(--rule-strong);
  text-transform: none;
}

.direction-text {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.process-list {
  border-top: 1px solid var(--rule);
}

.process-row {
  display: grid;
  grid-template-columns: 56px minmax(140px, 1fr) minmax(0, 1fr) minmax(0, 1.2fr);
  gap: 20px;
  align-items: start;
  padding: 20px 0;
  border-bottom: 1px solid var(--rule);
}

.process-no {
  font-family: var(--serif);
  font-size: 24px;
  font-weight: 700;
  color: var(--accent);
  line-height: 1.2;
}

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

.process-name {
  font-size: 18px;
  margin-bottom: 4px;
}

.process-label {
  margin: 0 0 4px;
  font-size: 13px;
  color: var(--rule-strong);
}

.process-text {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.entry-paths {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}

.entry-card {
  padding: 22px 24px;
  border: 1px solid var(--rule);
  border-radius: 6px;
  background-color: #fff;
}

.entry-name {
  font-size: 18px;
  margin-bottom: 10px;
}

.entry-text {
  font-size: 15px;
  margin-bottom: 14px;
}

/* ============================================================
   pages — 内页通用区块
   ============================================================ */

.section {
  margin-bottom: 40px;
  padding-bottom: 30px;
  border-bottom: 1px solid var(--rule);
}

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

.content-section {
  margin-bottom: 40px;
  padding-bottom: 30px;
  border-bottom: 1px solid var(--rule);
}

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

/* 服务方向页 */

.direction-card {
  display: grid;
  grid-template-columns: minmax(220px, 320px) minmax(0, 1fr);
  gap: 26px;
  align-items: start;
  padding: 26px 0;
  border-bottom: 1px solid var(--rule);
}

.direction-card:first-of-type {
  border-top: 1px solid var(--rule);
}

.direction-media img {
  aspect-ratio: 4 / 3;
}

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

.direction-body .direction-name {
  font-size: 20px;
  margin-bottom: 14px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--rule);
}

.direction-fields {
  margin: 0;
  display: grid;
  gap: 12px;
}

.direction-fields dt,
.direction-fields dd {
  margin: 0;
}

.direction-fields .field-label {
  font-size: 13px;
  color: var(--rule-strong);
  margin-bottom: 2px;
}

.direction-fields .field-value {
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink-soft);
}

.choose-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 22px;
}

.choose-item {
  padding: 20px 22px;
  border: 1px solid var(--rule);
  border-radius: 6px;
  background-color: #fff;
}

.choose-title {
  font-size: 17px;
  margin-bottom: 8px;
}

.choose-text {
  font-size: 15px;
  margin: 0;
}

.next-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  border-top: 1px solid var(--rule);
  padding-top: 16px;
}

.next-item {
  font-size: 15px;
  color: var(--ink-soft);
}

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

.next-label {
  display: inline-block;
  min-width: 96px;
  color: var(--rule-strong);
  font-size: 14px;
}

/* 合作流程页 */

.step-list {
  border-top: 1px solid var(--rule);
}

.step-item {
  display: grid;
  grid-template-columns: 64px minmax(0, 1fr);
  gap: 22px;
  align-items: start;
  padding: 24px 0;
  border-bottom: 1px solid var(--rule);
}

.step-index {
  font-family: var(--serif);
  font-size: 28px;
  font-weight: 700;
  color: var(--accent);
  line-height: 1.1;
}

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

.step-name {
  font-size: 19px;
  margin-bottom: 10px;
}

.step-meta {
  font-size: 14px;
  color: var(--ink-soft);
  margin-bottom: 6px;
}

.step-meta strong {
  color: var(--ink);
}

.step-note {
  font-size: 15px;
  color: var(--ink-soft);
  margin: 0;
}

.material-groups {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 22px;
}

.material-group {
  padding: 20px 22px;
  border: 1px solid var(--rule);
  border-radius: 6px;
  background-color: #fff;
}

.material-group-title {
  font-size: 16px;
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rule);
}

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

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

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

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

.scene-columns {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
  margin-top: 22px;
}

.scene-column {
  min-width: 0;
}

.scene-column-title {
  font-size: 17px;
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rule);
}

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

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

.scene-item::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--rule-strong);
}

.related-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 14px;
}

.related-item {
  padding: 14px 16px;
  border: 1px solid var(--rule);
  border-radius: 6px;
  background-color: #fff;
  font-size: 15px;
}

.related-link {
  color: var(--ink);
  font-weight: 600;
}

.related-link:hover,
.related-link:focus-visible {
  color: var(--accent);
  text-decoration: none;
}

.aside-nav-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  counter-reset: aside-step;
}

.aside-nav-item {
  position: relative;
  padding-left: 30px;
  font-size: 14px;
  line-height: 1.6;
  color: var(--ink-soft);
  counter-increment: aside-step;
}

.aside-nav-item::before {
  content: counter(aside-step);
  position: absolute;
  left: 0;
  top: 1px;
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  font-weight: 700;
  color: var(--ink-soft);
  border: 1px solid var(--rule-strong);
  border-radius: 50%;
}

.aside-nav-item.is-current {
  color: var(--accent);
  font-weight: 600;
}

.aside-nav-item.is-current::before {
  color: #fff;
  background-color: var(--accent);
  border-color: var(--accent);
}

/* 交付标准页 */

.section-figure img {
  aspect-ratio: 21 / 9;
  margin-bottom: 0;
}

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

.rounds-note {
  margin-top: 22px;
  padding: 18px 20px;
  border-left: 3px solid var(--accent);
  background-color: var(--paper-alt);
  border-radius: 0 4px 4px 0;
}

.rounds-title {
  font-size: 16px;
  margin-bottom: 8px;
}

.rounds-text {
  font-size: 15px;
  color: var(--ink-soft);
  margin: 0;
}

.acceptance-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 22px;
  margin-top: 22px;
}

.acceptance-item {
  padding: 20px 22px;
  border: 1px solid var(--rule);
  border-radius: 6px;
  background-color: #fff;
}

.acceptance-title {
  font-size: 16px;
  margin-bottom: 10px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rule);
}

.acceptance-desc {
  font-size: 15px;
  color: var(--ink-soft);
  margin-bottom: 10px;
}

.acceptance-meta {
  font-size: 14px;
  color: var(--ink-soft);
  margin: 0;
}

.boundary-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  border-top: 1px solid var(--rule);
  padding-top: 16px;
}

.boundary-item {
  position: relative;
  padding-left: 18px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink-soft);
}

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

/* 常见问题页 */

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

.page-figure {
  margin-bottom: 34px;
}

.faq-stage {
  margin-bottom: 36px;
  padding-bottom: 26px;
  border-bottom: 1px solid var(--rule);
}

.faq-stage:last-of-type {
  border-bottom: 0;
  padding-bottom: 0;
}

.faq-next {
  margin-top: 8px;
  padding: 26px 0 0;
  border-top: 2px solid var(--ink);
}

.stage-index {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.stage-index-item {
  font-size: 14px;
  line-height: 1.6;
  color: var(--ink-soft);
}

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

.error-main {
  padding-top: 56px;
  padding-bottom: 80px;
}

.error-panel {
  max-width: 720px;
  padding: 40px 0 0;
  border-top: 2px solid var(--ink);
}

.error-code {
  font-family: var(--serif);
  font-size: 64px;
  font-weight: 700;
  line-height: 1;
  color: var(--accent);
  margin: 0 0 16px;
}

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

.error-lead {
  font-size: 16px;
  color: var(--ink-soft);
  max-width: 620px;
  margin-bottom: 24px;
}

.error-paths {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 12px;
  margin-bottom: 24px;
}

.error-link {
  display: block;
  min-height: 44px;
  padding: 11px 16px;
  font-size: 15px;
  color: var(--ink);
  border: 1px solid var(--rule);
  border-radius: 4px;
  background-color: #fff;
}

.error-link:hover,
.error-link:focus-visible {
  color: var(--accent);
  border-color: var(--accent);
  text-decoration: none;
}

.error-note {
  font-size: 14px;
  color: var(--ink-soft);
  padding-top: 18px;
  border-top: 1px solid var(--rule);
  margin: 0;
}

/* ============================================================
   components — 页脚
   ============================================================ */

.site-footer {
  margin-top: 40px;
  background-color: var(--paper-alt);
  border-top: 2px solid var(--ink);
}

.footer-inner {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 40px 24px 28px;
}

.footer-groups {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 28px;
  padding-bottom: 26px;
  border-bottom: 1px solid var(--rule);
}

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

.footer-group-title {
  font-size: 15px;
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rule);
}

.footer-list {
  display: flex;
  flex-direction: column;
  gap: 9px;
}

.footer-link {
  font-size: 14px;
  color: var(--ink-soft);
}

.footer-link:hover,
.footer-link:focus-visible {
  color: var(--accent);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 26px;
  padding: 18px 0;
  border-bottom: 1px solid var(--rule);
}

.footer-brand {
  padding-top: 20px;
}

.footer-brand-name {
  font-family: var(--serif);
  font-size: 18px;
  font-weight: 700;
  color: var(--ink);
  margin: 0 0 6px;
}

.footer-brand-note {
  font-size: 14px;
  color: var(--ink-soft);
  margin: 0 0 8px;
  max-width: 640px;
}

.footer-copy {
  font-size: 13px;
  color: var(--rule-strong);
  margin: 0;
}

/* ============================================================
   responsive — 1080px
   ============================================================ */

@media (max-width: 1080px) {
  .header-inner {
    padding: 16px 20px 12px;
  }

  .subnav-list {
    padding: 10px 20px;
  }

  .site-main {
    padding: 0 20px 56px;
  }

  .footer-inner {
    padding: 34px 20px 24px;
  }

  .hero-layout {
    grid-template-columns: 210px minmax(0, 1fr);
    gap: 30px;
  }

  .page-layout {
    grid-template-columns: minmax(0, 1fr) 240px;
    gap: 30px;
  }

  .footer-groups {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px;
  }

  .direction-row {
    grid-template-columns: minmax(120px, 1fr) minmax(0, 1fr) minmax(0, 1fr) minmax(0, 1fr);
    gap: 16px;
  }
}

/* ============================================================
   responsive — 720px
   ============================================================ */

@media (max-width: 720px) {
  body.site-body {
    font-size: 15px;
  }

  .header-inner {
    padding: 12px 16px 10px;
    gap: 10px;
  }

  .brand {
    font-size: 19px;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    order: 3;
    flex-basis: 100%;
    margin-left: 0;
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    width: 100%;
    padding: 6px 0 4px;
    border-top: 1px solid var(--rule);
  }

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

  .nav-list li {
    border-bottom: 1px solid var(--rule);
  }

  .nav-list li:last-child {
    border-bottom: 0;
  }

  .nav-link {
    display: block;
    min-height: 44px;
    padding: 12px 4px;
    font-size: 16px;
    border-bottom: 0;
  }

  .nav-link.is-current {
    border-bottom: 0;
    color: var(--accent);
  }

  .subnav-list {
    padding: 8px 16px;
    gap: 6px 18px;
  }

  .subnav-link {
    min-height: 32px;
    padding: 6px 0;
    font-size: 13px;
  }

  .site-main {
    padding: 0 16px 44px;
  }

  .inner-main {
    padding-top: 18px;
  }

  .breadcrumb {
    font-size: 13px;
    margin-bottom: 18px;
    padding-bottom: 12px;
  }

  .page-header {
    margin-bottom: 26px;
    padding-bottom: 18px;
  }

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

  .page-description {
    font-size: 15px;
  }

  .section-title {
    font-size: 20px;
  }

  .hero-section {
    padding: 26px 0 32px;
  }

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

  .hero-main {
    order: 1;
  }

  .hero-index {
    order: 2;
  }

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

  .hero-lead {
    font-size: 15px;
  }

  .hero-actions {
    gap: 12px;
  }

  .btn {
    flex: 1 1 auto;
    text-align: center;
  }

  .content-media-primary {
    margin-top: 26px;
  }

  .directions-section,
  .process-section,
  .standards-section,
  .faq-section,
  .entry-section {
    padding: 30px 0;
  }

  .direction-row {
    grid-template-columns: minmax(0, 1fr);
    gap: 12px;
    padding: 18px 0;
  }

  .direction-col-name {
    padding-bottom: 8px;
    border-bottom: 1px solid var(--rule);
  }

  .process-row {
    grid-template-columns: 44px minmax(0, 1fr);
    gap: 8px 16px;
    padding: 18px 0;
  }

  .process-col-owner,
  .process-col-output {
    grid-column: 2;
  }

  .process-no {
    font-size: 20px;
    grid-row: span 3;
  }

  .entry-paths {
    grid-template-columns: minmax(0, 1fr);
    gap: 18px;
  }

  .page-layout {
    grid-template-columns: minmax(0, 1fr);
    gap: 30px;
  }

  .layout-main {
    order: 1;
  }

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

  .direction-card {
    grid-template-columns: minmax(0, 1fr);
    gap: 18px;
    padding: 22px 0;
  }

  .choose-list,
  .material-groups,
  .scene-columns,
  .acceptance-list,
  .related-list {
    grid-template-columns: minmax(0, 1fr);
    gap: 16px;
  }

  .step-item {
    grid-template-columns: 44px minmax(0, 1fr);
    gap: 14px;
    padding: 20px 0;
  }

  .step-index {
    font-size: 22px;
  }

  .step-name {
    font-size: 17px;
  }

  .data-table {
    min-width: 480px;
    font-size: 14px;
  }

  .data-table thead th,
  .data-table tbody th,
  .data-table tbody td {
    padding: 10px 12px;
  }

  .faq-question {
    font-size: 16px;
    padding: 14px 34px 14px 0;
  }

  .faq-answer {
    font-size: 14px;
  }

  .next-label {
    display: block;
    min-width: 0;
    margin-bottom: 2px;
  }

  .error-main {
    padding-top: 36px;
    padding-bottom: 56px;
  }

  .error-code {
    font-size: 48px;
  }

  .error-main h1 {
    font-size: 24px;
  }

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

  .footer-inner {
    padding: 30px 16px 22px;
  }

  .footer-groups {
    grid-template-columns: minmax(0, 1fr);
    gap: 20px;
    padding-bottom: 20px;
  }

  .footer-legal {
    flex-direction: column;
    gap: 10px;
    padding: 16px 0;
  }

  .footer-link {
    display: inline-block;
    min-height: 30px;
  }
}

/* ============================================================
   responsive — 420px
   ============================================================ */

@media (max-width: 420px) {
  .hero-title {
    font-size: 24px;
  }

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

  .direction-name,
  .process-name {
    font-size: 17px;
  }

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

  .process-no {
    grid-row: auto;
  }

  .process-col-owner,
  .process-col-output {
    grid-column: auto;
  }

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

  .data-table {
    min-width: 420px;
  }
}