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

:root {
  --color-ink: #1f2937;
  --color-paper: #f6f4ef;
  --color-ochre: #b45309;
  --color-teal: #0f766e;
  --color-white: #ffffff;
  --color-gray-100: #f3f4f6;
  --color-gray-200: #e5e7eb;
  --color-gray-300: #d1d5db;
  --color-gray-400: #9ca3af;
  --color-gray-500: #6b7280;
  --color-gray-600: #4b5563;
  --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
  --font-mono: 'Inter', 'SF Mono', 'Menlo', monospace;
  --container-width: min(1140px, 92vw);
  --content-width: 780px;
  --main-width: 768px;
  --sidebar-width: 280px;
  --radius-sm: 4px;
  --radius-md: 8px;
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-5: 48px;
  --space-6: 64px;
  --space-7: 96px;
}

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

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

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.8;
  color: var(--color-ink);
  background-color: var(--color-paper);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

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

ul,
ol {
  list-style: none;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 600;
  line-height: 1.4;
  color: var(--color-ink);
}

h1 {
  font-size: 32px;
  line-height: 1.4;
}

h2 {
  font-size: 24px;
  line-height: 1.5;
}

h3 {
  font-size: 18px;
  line-height: 1.6;
}

p {
  margin-bottom: 16px;
}

strong {
  font-weight: 600;
}

/* ==========================================================================
   layout shell
   ========================================================================== */

.site-body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

.site-header {
  background-color: var(--color-white);
  border-bottom: 1px solid var(--color-gray-200);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  min-height: 72px;
  display: flex;
  align-items: center;
  gap: 32px;
  padding: 12px 0;
}

.brand-link {
  display: flex;
  flex-direction: column;
  gap: 2px;
  flex-shrink: 0;
}

.brand-name {
  font-size: 22px;
  font-weight: 700;
  color: var(--color-ink);
  line-height: 1.2;
  letter-spacing: 0;
}

.brand-slogan {
  font-size: 12px;
  color: var(--color-gray-500);
  line-height: 1.4;
}

.main-nav ul {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-link {
  font-size: 15px;
  color: var(--color-gray-600);
  padding: 6px 0;
  position: relative;
  white-space: nowrap;
}

.nav-link::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 2px;
  background-color: var(--color-ochre);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.25s ease;
}

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

.nav-link:hover::after {
  transform: scaleX(1);
}

.nav-link.is-current {
  color: var(--color-ink);
  font-weight: 600;
}

.nav-link.is-current::after {
  transform: scaleX(1);
}

.header-tools {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 20px;
}

.tool-link {
  font-size: 14px;
  color: var(--color-gray-600);
  padding: 6px 0;
  border-bottom: 1px solid transparent;
}

.tool-link:hover {
  color: var(--color-ochre);
  border-bottom-color: var(--color-ochre);
}

.mobile-nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 10px;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  border-radius: var(--radius-sm);
}

.mobile-nav-toggle:hover {
  background-color: var(--color-gray-100);
}

.toggle-bar {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-ink);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.site-footer {
  background-color: var(--color-white);
  border-top: 1px solid var(--color-gray-200);
  margin-top: var(--space-7);
}

.footer-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: var(--space-5) 0 var(--space-4);
  display: grid;
  grid-template-columns: 280px 1fr 1fr 1fr 1fr;
  gap: 40px;
}

.footer-brand-link {
  display: inline-block;
}

.footer-desc {
  font-size: 14px;
  color: var(--color-gray-500);
  margin-top: 12px;
  line-height: 1.7;
}

.footer-links-group h3 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--color-ink);
}

.footer-links-group ul li {
  margin-bottom: 10px;
}

.footer-links-group a {
  font-size: 14px;
  color: var(--color-gray-500);
}

.footer-links-group a:hover {
  color: var(--color-ochre);
}

.footer-bottom {
  border-top: 1px solid var(--color-gray-200);
  padding: 20px 0;
}

.footer-bottom p {
  max-width: var(--container-width);
  margin: 0 auto;
  font-size: 13px;
  color: var(--color-gray-400);
  margin-bottom: 0;
}

/* ==========================================================================
   components
   ========================================================================== */

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--color-gray-500);
  margin-bottom: var(--space-4);
}

.breadcrumb a {
  color: var(--color-gray-500);
}

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

.breadcrumb-sep {
  color: var(--color-gray-400);
}

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

.page-header {
  margin-bottom: var(--space-4);
}

.page-title {
  font-size: 32px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--color-ink);
  margin-bottom: 0;
}

.page-title-block {
  margin-bottom: var(--space-5);
}

.page-intro {
  font-size: 16px;
  color: var(--color-gray-600);
  max-width: 720px;
}

.section-heading {
  margin-bottom: var(--space-4);
}

.section-intro {
  font-size: 16px;
  color: var(--color-gray-600);
  max-width: 680px;
  margin-top: 8px;
}

.section-link {
  display: inline-block;
  font-size: 15px;
  font-weight: 600;
  color: var(--color-ochre);
  margin-top: var(--space-3);
  border-bottom: 2px solid transparent;
  transition: border-color 0.2s ease;
}

.section-link:hover {
  border-bottom-color: var(--color-ochre);
}

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

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

.btn-primary:hover {
  background-color: #92400e;
  border-color: #92400e;
  color: var(--color-white);
}

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

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

.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) var(--sidebar-width);
  gap: 48px;
  align-items: start;
}

.main-content {
  min-width: 0;
  min-width: 520px;
}

.related-sidebar {
  min-width: 0;
}

.related-sidebar h2,
.sidebar-related h2,
.page-sidebar h2 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: var(--space-3);
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-gray-200);
}

.related-links li {
  margin-bottom: 12px;
}

.related-links a {
  font-size: 15px;
  color: var(--color-teal);
  display: inline-block;
  padding: 4px 0;
}

.related-links a:hover {
  color: var(--color-ochre);
}

.related-desc {
  display: block;
  font-size: 13px;
  color: var(--color-gray-500);
  line-height: 1.6;
  margin-top: 2px;
}

.sidebar-module {
  margin-bottom: var(--space-4);
}

.sidebar-link-list li {
  margin-bottom: 12px;
}

.sidebar-link-list a {
  font-size: 15px;
  color: var(--color-teal);
  padding: 4px 0;
  display: inline-block;
}

.sidebar-link-list a:hover {
  color: var(--color-ochre);
}

.related-module h2 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: var(--space-3);
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-gray-200);
}

.related-module .related-links li {
  margin-bottom: 12px;
}

.related-module .related-links a {
  font-size: 15px;
  color: var(--color-teal);
  display: inline-block;
  padding: 4px 0;
}

.related-module .related-links a:hover {
  color: var(--color-ochre);
}

figure {
  margin: 0;
}

figcaption {
  font-size: 13px;
  color: var(--color-gray-500);
  text-align: center;
  margin-top: 8px;
  line-height: 1.6;
}

/* ==========================================================================
   pages — index
   ========================================================================== */

.home-main {
  overflow: visible;
}

/* hero */

.hero {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: var(--space-6) 0 var(--space-7);
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 56px;
  align-items: center;
}

.hero-content {
  max-width: 640px;
}

.hero h1 {
  font-size: 32px;
  line-height: 1.4;
  font-weight: 700;
  margin-bottom: var(--space-3);
}

.hero-lead {
  font-size: 18px;
  color: var(--color-gray-600);
  margin-bottom: var(--space-2);
}

.hero-sub-lead {
  font-size: 16px;
  color: var(--color-gray-500);
  margin-bottom: var(--space-4);
}

.hero-actions {
  display: flex;
  gap: 16px;
  margin-bottom: var(--space-4);
}

.hero-next-hint {
  font-size: 14px;
  color: var(--color-gray-400);
  margin-bottom: 0;
}

.hero-figure {
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--color-gray-100);
}

.hero-figure img {
  width: 100%;
  height: 360px;
  object-fit: cover;
}

/* services-index */

.services-index {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: var(--space-6) 0;
}

.services-layout {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 48px;
}

.services-list {
  border-left: 2px solid var(--color-gray-200);
  padding-left: var(--space-3);
}

.service-item-title {
  font-size: 16px;
  font-weight: 500;
  color: var(--color-gray-500);
  margin-bottom: 12px;
  cursor: default;
  transition: color 0.2s ease;
}

.service-item-title:hover {
  color: var(--color-ochre);
}

.services-details {
  min-width: 0;
}

.service-detail-item {
  padding: var(--space-4) 0;
  border-bottom: 1px solid var(--color-gray-200);
}

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

.service-detail-item h3 {
  font-size: 20px;
  margin-bottom: var(--space-2);
}

.service-detail-item p {
  color: var(--color-gray-600);
  margin-bottom: 12px;
}

.service-detail-item .service-boundary-note {
  font-size: 14px;
  color: var(--color-gray-500);
  background-color: var(--color-gray-100);
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  margin-bottom: 12px;
}

.detail-link {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-ochre);
  display: inline-block;
  border-bottom: 2px solid transparent;
  transition: border-color 0.2s ease;
}

.detail-link:hover {
  border-bottom-color: var(--color-ochre);
}

.services-figure {
  margin-top: var(--space-5);
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--color-gray-100);
}

.services-figure img {
  width: 100%;
  height: 300px;
  object-fit: cover;
}

/* method-summary */

.method-summary {
  background-color: var(--color-white);
  border-top: 1px solid var(--color-gray-200);
  border-bottom: 1px solid var(--color-gray-200);
  padding: var(--space-6) 0;
}

.method-summary-inner {
  max-width: var(--container-width);
  margin: 0 auto;
}

.method-quote {
  font-size: 18px;
  color: var(--color-gray-600);
  max-width: 680px;
  margin-bottom: var(--space-4);
}

.method-points {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.method-point {
  border-left: 2px solid var(--color-gray-200);
  padding-left: var(--space-3);
}

.method-point h3 {
  font-size: 17px;
  margin-bottom: 8px;
}

.method-point p {
  font-size: 15px;
  color: var(--color-gray-600);
  margin-bottom: 0;
}

/* topics-preview */

.topics-preview {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: var(--space-6) 0;
}

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

.topic-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.topic-card:hover {
  border-color: var(--color-gray-300);
  box-shadow: 0 2px 8px rgba(31, 41, 55, 0.06);
}

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

.topic-card p {
  font-size: 14px;
  color: var(--color-gray-600);
  margin-bottom: 12px;
}

.topic-link {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-ochre);
}

.topic-link:hover {
  text-decoration: underline;
}

/* cooperation-steps */

.cooperation-steps {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: var(--space-6) 0;
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.step-item {
  padding: var(--space-4);
  background-color: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-md);
}

.step-item .step-number {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--color-ochre);
  font-weight: 700;
  margin-bottom: 8px;
}

.step-item h3 {
  font-size: 17px;
  margin-bottom: 8px;
}

.step-item p {
  font-size: 14px;
  color: var(--color-gray-600);
  margin-bottom: 0;
}

/* faq-preview */

.faq-preview {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: var(--space-6) 0;
}

.faq-preview-list {
  max-width: 780px;
}

.faq-preview-item {
  padding: var(--space-3) 0;
  border-bottom: 1px solid var(--color-gray-200);
}

.faq-preview-item:first-child {
  border-top: 1px solid var(--color-gray-200);
}

.faq-preview-item h3 {
  font-size: 17px;
  margin-bottom: 4px;
}

.faq-preview-item p {
  font-size: 15px;
  color: var(--color-gray-600);
  margin-bottom: 8px;
}

.faq-link {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-ochre);
}

.faq-link:hover {
  text-decoration: underline;
}

/* ==========================================================================
   pages — inner
   ========================================================================== */

.inner-main {
  padding-top: var(--space-5);
}

.layout-shell {
  max-width: var(--container-width);
  margin: 0 auto;
}

.page-layout {
  max-width: var(--container-width);
  margin: 0 auto;
}

/* services page */

.service-item {
  padding: var(--space-4) 0;
  border-bottom: 1px solid var(--color-gray-200);
  display: grid;
  grid-template-columns: 1fr 220px;
  gap: 32px;
  align-items: start;
}

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

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

.service-item h2 {
  font-size: 22px;
  margin-bottom: var(--space-2);
}

.service-scene,
.service-method,
.service-boundary {
  font-size: 15px;
  color: var(--color-gray-600);
  margin-bottom: 12px;
}

.service-scene::before {
  content: '适用场景：';
  font-weight: 600;
  color: var(--color-ink);
}

.service-method::before {
  content: '工作方式：';
  font-weight: 600;
  color: var(--color-ink);
}

.service-boundary::before {
  content: '服务边界：';
  font-weight: 600;
  color: var(--color-ink);
}

.service-figure {
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--color-gray-100);
}

.service-figure img {
  width: 100%;
  height: 180px;
  object-fit: cover;
}

.service-boundary-block {
  margin-top: var(--space-5);
  padding: var(--space-4);
  background-color: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-md);
}

.service-boundary-block h2 {
  font-size: 20px;
  margin-bottom: var(--space-2);
}

.service-boundary-block p {
  font-size: 15px;
  color: var(--color-gray-600);
  margin-bottom: 0;
}

/* methods page */

.method-steps {
  margin-bottom: var(--space-5);
}

.method-steps > h2 {
  margin-bottom: var(--space-2);
}

.section-lead {
  font-size: 16px;
  color: var(--color-gray-600);
  margin-bottom: var(--space-4);
}

.method-step {
  display: grid;
  grid-template-columns: 56px 1fr;
  gap: 24px;
  padding: var(--space-3) 0;
  border-bottom: 1px solid var(--color-gray-200);
}

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

.method-step .step-number {
  font-family: var(--font-mono);
  font-size: 32px;
  font-weight: 700;
  color: var(--color-ochre);
  line-height: 1.2;
}

.step-content h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.step-action,
.step-result,
.step-alert {
  font-size: 15px;
  color: var(--color-gray-600);
  margin-bottom: 8px;
}

.step-action::before {
  content: '动作：';
  font-weight: 600;
  color: var(--color-ink);
}

.step-result::before {
  content: '预期结果：';
  font-weight: 600;
  color: var(--color-ink);
}

.step-alert::before {
  content: '异常提示：';
  font-weight: 600;
  color: var(--color-ochre);
}

.method-figure {
  margin: var(--space-5) 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--color-gray-100);
}

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

.evidence-section {
  margin-top: var(--space-5);
  padding: var(--space-4);
  background-color: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-md);
}

.evidence-section > h2 {
  margin-bottom: var(--space-2);
}

.evidence-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-top: var(--space-3);
}

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

.evidence-item ul {
  list-style: disc;
  padding-left: 20px;
}

.evidence-item li {
  font-size: 14px;
  color: var(--color-gray-600);
  margin-bottom: 6px;
  line-height: 1.6;
}

.evidence-note {
  font-size: 14px;
  color: var(--color-gray-500);
  margin-top: var(--space-3);
  padding-top: var(--space-3);
  border-top: 1px solid var(--color-gray-200);
}

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

/* topics page */

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

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

.topics-hero-figure {
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--color-gray-100);
  margin-bottom: var(--space-5);
}

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

.topic-list-section {
  margin-bottom: var(--space-5);
}

.topic-list-section > h2 {
  margin-bottom: var(--space-3);
}

.topic-entry {
  padding: var(--space-3) 0;
  border-bottom: 1px solid var(--color-gray-200);
}

.topic-entry:first-child {
  border-top: 1px solid var(--color-gray-200);
}

.topic-entry h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.topic-entry h3 a {
  color: var(--color-ink);
}

.topic-entry h3 a:hover {
  color: var(--color-ochre);
}

.topic-entry > p {
  font-size: 15px;
  color: var(--color-gray-600);
  margin-bottom: 8px;
}

.topic-link-row a {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-ochre);
}

.topic-link-row a:hover {
  text-decoration: underline;
}

.topic-relations-section {
  margin-top: var(--space-5);
  padding: var(--space-4);
  background-color: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-md);
}

.topic-relations-section h2 {
  font-size: 20px;
  margin-bottom: var(--space-2);
}

.topic-relations-section p {
  font-size: 15px;
  color: var(--color-gray-600);
  margin-bottom: 12px;
}

.topic-relations-section strong {
  font-weight: 600;
  color: var(--color-ink);
}

/* faq page */

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

.faq-lead-image {
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--color-gray-100);
  margin-bottom: var(--space-5);
}

.faq-lead-image img {
  width: 100%;
  height: 240px;
  object-fit: cover;
}

.faq-section-block {
  margin-bottom: var(--space-5);
}

.faq-section-block > h2 {
  margin-bottom: var(--space-3);
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-gray-200);
}

.faq-item {
  border-bottom: 1px solid var(--color-gray-200);
}

.faq-item summary {
  font-size: 16px;
  font-weight: 600;
  color: var(--color-ink);
  padding: 16px 0;
  cursor: pointer;
  list-style: none;
  position: relative;
  padding-right: 32px;
}

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

.faq-item summary::after {
  content: '+';
  position: absolute;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  font-size: 20px;
  color: var(--color-ochre);
  font-weight: 400;
}

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

.faq-item p {
  font-size: 15px;
  color: var(--color-gray-600);
  padding-bottom: 16px;
  margin-bottom: 0;
}

.faq-note-block {
  margin-top: var(--space-5);
  padding: var(--space-4);
  background-color: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-md);
}

.faq-note-block h2 {
  font-size: 20px;
  margin-bottom: var(--space-2);
}

.faq-note-block p {
  font-size: 15px;
  color: var(--color-gray-600);
  margin-bottom: 0;
}

.faq-note-block a {
  font-weight: 600;
}

/* cooperation page */

.cooperation-layout {
  grid-template-columns: minmax(0, 1fr) 260px;
}

.cooperation-process {
  margin-bottom: var(--space-5);
}

.cooperation-process > h2 {
  margin-bottom: var(--space-2);
}

.cooperation-process > p {
  font-size: 15px;
  color: var(--color-gray-600);
  margin-bottom: var(--space-4);
}

.process-step {
  padding: var(--space-3) 0;
  border-bottom: 1px solid var(--color-gray-200);
}

.process-step:first-child {
  border-top: 1px solid var(--color-gray-200);
}

.process-step h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.process-step > p {
  font-size: 15px;
  color: var(--color-gray-600);
  margin-bottom: 8px;
}

.step-note {
  font-size: 14px;
  color: var(--color-gray-500);
  background-color: var(--color-gray-100);
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  margin-bottom: 0;
}

.step-note strong {
  font-weight: 600;
  color: var(--color-gray-600);
}

.checklist-section {
  margin-bottom: var(--space-5);
  padding: var(--space-4);
  background-color: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-md);
}

.checklist-section > h2 {
  margin-bottom: var(--space-2);
}

.checklist-section > p {
  font-size: 15px;
  color: var(--color-gray-600);
  margin-bottom: var(--space-3);
}

.checklist-list {
  list-style: disc;
  padding-left: 20px;
}

.checklist-list li {
  font-size: 15px;
  color: var(--color-gray-600);
  margin-bottom: 8px;
  line-height: 1.6;
}

.feedback-note {
  padding: var(--space-4);
  background-color: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-md);
}

.feedback-note h2 {
  font-size: 20px;
  margin-bottom: var(--space-2);
}

.feedback-note p {
  font-size: 15px;
  color: var(--color-gray-600);
  margin-bottom: 12px;
}

.feedback-figure {
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--color-gray-100);
  margin-top: var(--space-3);
}

.feedback-figure img {
  width: 100%;
  height: 220px;
  object-fit: cover;
}

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

.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-7) var(--space-3);
  min-height: 60vh;
}

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

.error-code {
  font-family: var(--font-mono);
  font-size: 72px;
  font-weight: 700;
  color: var(--color-ochre);
  line-height: 1.2;
  margin-bottom: var(--space-2);
}

.error-section h1 {
  font-size: 28px;
  margin-bottom: var(--space-2);
}

.error-desc {
  font-size: 16px;
  color: var(--color-gray-600);
  margin-bottom: var(--space-4);
}

.error-action {
  display: inline-block;
  padding: 10px 24px;
  background-color: var(--color-ochre);
  color: var(--color-white);
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-ochre);
  transition: background-color 0.2s ease;
}

.error-action:hover {
  background-color: #92400e;
  color: var(--color-white);
}

/* ==========================================================================
   related links bottom nav (inner pages)
   ========================================================================== */

.related-links-nav {
  max-width: var(--container-width);
  margin: var(--space-5) auto 0;
  padding: var(--space-3) 0;
  border-top: 1px solid var(--color-gray-200);
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.related-links-label {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-gray-500);
}

.related-links-item {
  font-size: 14px;
  color: var(--color-teal);
  padding: 4px 0;
}

.related-links-item:hover {
  color: var(--color-ochre);
}

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

@media (max-width: 1024px) {
  .header-inner {
    gap: 20px;
  }

  .main-nav ul {
    gap: 20px;
  }

  .footer-inner {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }

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

  .hero {
    gap: 40px;
  }

  .hero-figure img {
    height: 320px;
  }

  .services-layout {
    grid-template-columns: 220px 1fr;
    gap: 32px;
  }

  .service-item {
    grid-template-columns: 1fr 180px;
    gap: 24px;
  }

  .page-layout {
    gap: 32px;
  }
}

@media (max-width: 900px) {
  .header-inner {
    flex-wrap: wrap;
    min-height: 64px;
    padding: 8px 0;
  }

  .mobile-nav-toggle {
    display: flex;
    margin-left: auto;
  }

  .main-nav {
    order: 3;
    width: 100%;
    display: none;
  }

  .main-nav.is-open {
    display: block;
  }

  .main-nav ul {
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    padding: 8px 0 16px;
  }

  .main-nav li {
    width: 100%;
  }

  .nav-link {
    display: block;
    padding: 12px 0;
    font-size: 16px;
    border-bottom: 1px solid var(--color-gray-100);
  }

  .header-tools {
    margin-left: auto;
  }

  .hero {
    grid-template-columns: 1fr;
    gap: 32px;
    padding: var(--space-5) 0;
  }

  .hero-figure {
    order: -1;
  }

  .hero-figure img {
    height: 280px;
  }

  .services-layout {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .services-list {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    border-left: none;
    padding-left: 0;
  }

  .service-item-title {
    margin-bottom: 0;
    padding: 6px 14px;
    background-color: var(--color-white);
    border: 1px solid var(--color-gray-200);
    border-radius: 999px;
    font-size: 14px;
  }

  .method-points {
    grid-template-columns: 1fr;
    gap: 24px;
  }

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

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

  .page-layout {
    grid-template-columns: 1fr;
    gap: 48px;
  }

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

  .related-sidebar,
  .sidebar-related,
  .page-sidebar {
    border-top: 1px solid var(--color-gray-200);
    padding-top: var(--space-4);
  }

  .service-item {
    grid-template-columns: 1fr;
  }

  .service-figure img {
    height: 200px;
  }

  .evidence-list {
    grid-template-columns: 1fr;
  }

  .method-step {
    grid-template-columns: 40px 1fr;
    gap: 16px;
  }

  .method-step .step-number {
    font-size: 24px;
  }

  .page-topics .page-layout,
  .page-faq .page-layout,
  .cooperation-layout {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 600px) {
  :root {
    --container-width: 92vw;
  }

  h1 {
    font-size: 28px;
  }

  h2 {
    font-size: 22px;
  }

  .header-tools {
    display: none;
  }

  .brand-slogan {
    display: none;
  }

  .hero {
    padding: var(--space-4) 0 var(--space-5);
  }

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

  .hero-lead {
    font-size: 16px;
  }

  .hero-actions {
    flex-direction: column;
    gap: 12px;
  }

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

  .hero-figure img {
    height: 220px;
  }

  .services-index {
    padding: var(--space-5) 0;
  }

  .services-details {
    padding: 0;
  }

  .service-detail-item {
    padding: var(--space-3) 0;
  }

  .service-detail-item h3 {
    font-size: 18px;
  }

  .services-figure img {
    height: 200px;
  }

  .method-summary {
    padding: var(--space-5) 0;
  }

  .topics-preview {
    padding: var(--space-5) 0;
  }

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

  .cooperation-steps {
    padding: var(--space-5) 0;
  }

  .faq-preview {
    padding: var(--space-5) 0;
  }

  .inner-main {
    padding-top: var(--space-4);
  }

  .breadcrumb {
    font-size: 13px;
    margin-bottom: var(--space-3);
    flex-wrap: wrap;
  }

  .page-header {
    margin-bottom: var(--space-3);
  }

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

  .page-title-block {
    margin-bottom: var(--space-4);
  }

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

  .service-item {
    padding: var(--space-3) 0;
  }

  .service-item h2 {
    font-size: 20px;
  }

  .service-figure img {
    height: 180px;
  }

  .method-step {
    grid-template-columns: 32px 1fr;
    gap: 12px;
    padding: var(--space-3) 0;
  }

  .method-step .step-number {
    font-size: 20px;
  }

  .method-figure img {
    height: 220px;
  }

  .evidence-list {
    gap: 16px;
  }

  .topics-hero-figure img {
    height: 200px;
  }

  .faq-lead-image img {
    height: 180px;
  }

  .faq-item summary {
    font-size: 15px;
    padding: 14px 28px 14px 0;
  }

  .feedback-figure img {
    height: 180px;
  }

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

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

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 24px;
    padding: var(--space-4) 0 var(--space-3);
  }

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

  .footer-links-group h3 {
    margin-bottom: 12px;
  }

  .footer-links-group ul li {
    margin-bottom: 8px;
  }

  .footer-bottom {
    padding: 16px 0;
  }

  .footer-bottom p {
    font-size: 12px;
  }

  .related-links-nav {
    margin-top: var(--space-4);
    gap: 12px;
  }
}

@media (max-width: 360px) {
  .brand-name {
    font-size: 18px;
  }

  .hero h1 {
    font-size: 24px;
  }

  .hero-figure img {
    height: 200px;
  }

  .services-figure img {
    height: 180px;
  }

  .method-figure img {
    height: 200px;
  }

  .topics-hero-figure img {
    height: 180px;
  }

  .faq-lead-image img {
    height: 160px;
  }

  .feedback-figure img {
    height: 160px;
  }
}