:root {
  --bg-page: #F7F8F5;
  --bg-surface: #FFFFFF;
  --bg-soft: #EEF2EC;
  --ink: #1F2A24;
  --ink-soft: #4C5A52;
  --ink-mute: #6E7A72;
  --line: #DDE3DC;
  --line-strong: #C6D0C6;
  --accent: #3E6B57;
  --accent-deep: #2C4E3F;
  --warm: #C97B4A;
  --radius: 6px;
  --radius-sm: 4px;
  --shadow-soft: 0 1px 2px rgba(31, 42, 36, 0.06), 0 6px 18px rgba(31, 42, 36, 0.05);
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", sans-serif;
  --width-shell: 1120px;
  --width-content: 760px;
  --width-aside: 220px;
}

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

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

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

.site-body {
  margin: 0;
  padding: 0;
  background-color: var(--bg-page);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4 {
  margin: 0;
  color: var(--ink);
  font-weight: 700;
  line-height: 1.4;
}

p {
  margin: 0;
}

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

a {
  color: var(--accent-deep);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.18s ease, border-color 0.18s ease;
}

a:hover,
a:focus-visible {
  color: var(--warm);
  border-bottom-color: currentColor;
}

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

figure {
  margin: 0;
}

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

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

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

.site-header {
  background-color: var(--bg-surface);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 20;
}

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

.brand {
  font-size: 19px;
  font-weight: 700;
  color: var(--ink);
  letter-spacing: 0;
  border-bottom: none;
  white-space: nowrap;
}

.brand:hover,
.brand:focus-visible {
  color: var(--accent);
  border-bottom-color: transparent;
}

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

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

.nav-item {
  display: block;
}

.nav-link {
  display: block;
  padding: 8px 12px;
  min-height: 40px;
  line-height: 24px;
  font-size: 15px;
  color: var(--ink-soft);
  border-radius: var(--radius-sm);
  border-bottom: none;
}

.nav-link:hover,
.nav-link:focus-visible {
  color: var(--accent-deep);
  background-color: var(--bg-soft);
  border-bottom-color: transparent;
}

.nav-link.is-current {
  color: var(--accent-deep);
  font-weight: 700;
  background-color: var(--bg-soft);
}

.nav-toggle {
  display: none;
  margin-left: auto;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  background-color: var(--bg-surface);
  color: var(--ink);
  cursor: pointer;
  position: relative;
}

.nav-toggle::before,
.nav-toggle::after {
  content: "";
  position: absolute;
  left: 12px;
  right: 12px;
  height: 2px;
  background-color: currentColor;
}

.nav-toggle::before {
  top: 16px;
}

.nav-toggle::after {
  bottom: 16px;
}

.site-main {
  display: block;
}

.home-main {
  max-width: var(--width-shell);
  margin: 0 auto;
  padding: 32px 24px 64px;
}

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

.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) var(--width-aside);
  gap: 40px;
  align-items: start;
}

.page-layout.sidebar-left,
.sidebar-left .page-layout {
  grid-template-columns: var(--width-aside) minmax(0, 1fr);
}

.page-content {
  min-width: 0;
  max-width: var(--width-content);
}

.site-footer {
  background-color: var(--bg-surface);
  border-top: 1px solid var(--line);
  margin-top: 24px;
}

.footer-inner {
  max-width: var(--width-shell);
  margin: 0 auto;
  padding: 40px 24px 24px;
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
  gap: 32px;
}

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

.footer-name {
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
}

.footer-slogan {
  margin-top: 6px;
  font-size: 14px;
  color: var(--accent);
}

.footer-desc {
  margin-top: 10px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-mute);
  max-width: 46ch;
}

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

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

.footer-col-title {
  font-size: 14px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 10px;
}

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

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

.footer-copy {
  max-width: var(--width-shell);
  margin: 0 auto;
  padding: 16px 24px 28px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  color: var(--ink-mute);
}

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

.btn {
  display: inline-block;
  min-height: 44px;
  padding: 10px 20px;
  line-height: 24px;
  font-size: 15px;
  font-weight: 700;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  border-bottom: 1px solid transparent;
}

.btn-primary {
  background-color: var(--accent);
  color: #FFFFFF;
  border-color: var(--accent);
}

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

.btn-ghost {
  background-color: transparent;
  color: var(--accent-deep);
  border-color: var(--line-strong);
}

.btn-ghost:hover,
.btn-ghost:focus-visible {
  background-color: var(--bg-soft);
  border-color: var(--accent);
  color: var(--accent-deep);
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--ink-mute);
  margin-bottom: 16px;
}

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

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

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

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

.page-header {
  padding-bottom: 20px;
  margin-bottom: 28px;
  border-bottom: 1px solid var(--line);
}

.page-title {
  font-size: 30px;
  font-weight: 700;
  line-height: 1.35;
  color: var(--ink);
}

.page-description {
  margin-top: 12px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
  max-width: 68ch;
}

.section {
  margin-bottom: 44px;
}

.section-title {
  font-size: 21px;
  font-weight: 700;
  color: var(--ink);
}

.section-lead,
.section-intro {
  margin-top: 10px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
  max-width: 68ch;
}

.section-foot {
  margin-top: 16px;
  font-size: 14px;
  color: var(--ink-mute);
}

.section-foot a {
  font-weight: 700;
}

.table-caption {
  caption-side: top;
  text-align: left;
  font-size: 13px;
  color: var(--ink-mute);
  padding-bottom: 10px;
}

.table-wrap {
  overflow-x: auto;
}

.data-table,
.field-table,
.compare-table {
  width: 100%;
  font-size: 14px;
  line-height: 1.7;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background-color: var(--bg-surface);
}

.data-table th,
.data-table td,
.field-table th,
.field-table td,
.compare-table th,
.compare-table td {
  padding: 10px 14px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--line);
}

.data-table thead th,
.field-table thead th,
.compare-table thead th {
  background-color: var(--bg-soft);
  color: var(--ink);
  font-weight: 700;
  white-space: nowrap;
}

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

.data-table tbody td,
.field-table tbody td,
.compare-table tbody td {
  color: var(--ink-soft);
}

.data-table tbody tr:last-child th,
.data-table tbody tr:last-child td,
.field-table tbody tr:last-child th,
.field-table tbody tr:last-child td,
.compare-table tbody tr:last-child th,
.compare-table tbody tr:last-child td {
  border-bottom: none;
}

.step-list {
  counter-reset: step;
  display: grid;
  gap: 14px;
}

.step-item {
  position: relative;
  padding: 16px 18px 16px 56px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.step-index {
  position: absolute;
  left: 16px;
  top: 16px;
  width: 26px;
  height: 26px;
  line-height: 26px;
  text-align: center;
  font-size: 13px;
  font-weight: 700;
  color: #FFFFFF;
  background-color: var(--accent);
  border-radius: 50%;
}

.step-name {
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
}

.step-text,
.step-body {
  margin-top: 6px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.step-body p {
  margin-top: 6px;
}

.content-figure,
.guide-figure,
.hero-media,
.content-media,
.channel-media,
.collection-media {
  background-color: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.content-figure img,
.guide-figure img,
.hero-media img,
.content-media img,
.channel-media img,
.collection-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.figure-caption,
.content-figure figcaption,
.guide-figure figcaption,
.hero-media figcaption,
.content-media figcaption,
.channel-media figcaption {
  padding: 10px 14px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--ink-mute);
  border-top: 1px solid var(--line);
}

/* ============ pages: home ============ */

.home-hero {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
  gap: 32px;
  padding-bottom: 36px;
  margin-bottom: 40px;
  border-bottom: 1px solid var(--line);
}

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

.hero-eyebrow {
  font-size: 13px;
  font-weight: 700;
  color: var(--warm);
}

.hero-title {
  margin-top: 10px;
  font-size: 32px;
  font-weight: 700;
  line-height: 1.35;
}

.hero-lead {
  margin-top: 14px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink-soft);
  max-width: 60ch;
}

.hero-lead strong {
  color: var(--ink);
}

.hero-note {
  margin-top: 12px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-mute);
  max-width: 60ch;
}

.hero-media {
  min-width: 0;
  aspect-ratio: 16 / 10;
  display: flex;
  flex-direction: column;
}

.hero-media img {
  flex: 1 1 auto;
  min-height: 0;
}

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

.entry-panel {
  padding: 20px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: border-color 0.18s ease, background-color 0.18s ease;
}

.entry-panel:hover {
  border-color: var(--line-strong);
  background-color: #FCFDFB;
}

.entry-title {
  font-size: 18px;
  font-weight: 700;
}

.entry-desc {
  margin-top: 8px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.entry-list {
  margin-top: 12px;
}

.entry-list li {
  border-top: 1px dashed var(--line);
}

.entry-list li:first-child {
  border-top: none;
}

.entry-list a {
  display: block;
  padding: 9px 0;
  min-height: 40px;
  font-size: 15px;
  color: var(--ink);
  border-bottom: none;
}

.entry-list a:hover,
.entry-list a:focus-visible {
  color: var(--accent);
  border-bottom-color: transparent;
}

.entry-more {
  display: inline-block;
  margin-top: 12px;
  font-size: 14px;
  font-weight: 700;
}

.content-media-primary {
  grid-column: 1 / -1;
  aspect-ratio: 21 / 9;
  display: flex;
  flex-direction: column;
}

.content-media-primary img {
  flex: 1 1 auto;
  min-height: 0;
}

.home-section {
  margin-bottom: 44px;
}

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

.section-desc {
  margin-top: 10px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
  max-width: 68ch;
}

.channel-rows {
  border-top: 1px solid var(--line);
}

.channel-row {
  display: grid;
  grid-template-columns: minmax(140px, 200px) minmax(0, 1fr) minmax(0, 1fr);
  gap: 20px;
  align-items: start;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
  transition: background-color 0.18s ease;
}

.channel-row:hover {
  background-color: var(--bg-soft);
}

.channel-row .channel-name {
  font-size: 17px;
  font-weight: 700;
}

.channel-row .channel-name a {
  color: var(--ink);
}

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

.channel-orient {
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.channel-fit {
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-mute);
}

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

.collection-card {
  padding: 20px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: border-color 0.18s ease, background-color 0.18s ease;
}

.collection-card:hover {
  border-color: var(--line-strong);
  background-color: #FCFDFB;
}

.collection-card .collection-name {
  font-size: 17px;
  font-weight: 700;
}

.collection-card .collection-name a {
  color: var(--ink);
}

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

.collection-range {
  margin-top: 10px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.collection-channel {
  margin-top: 10px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-mute);
}

.collection-channel a {
  margin-right: 8px;
}

.home-fields .field-table {
  margin-top: 4px;
}

.path-steps {
  display: grid;
  gap: 14px;
}

.path-step {
  position: relative;
  padding: 16px 18px 16px 56px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

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

.update-list {
  border-top: 1px solid var(--line);
}

.update-item {
  display: grid;
  grid-template-columns: minmax(120px, 160px) minmax(0, 1fr);
  gap: 20px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.update-date {
  font-size: 14px;
  color: var(--ink-mute);
  font-variant-numeric: tabular-nums;
}

.update-text {
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.feedback-note {
  margin-top: 22px;
  padding: 20px;
  background-color: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.feedback-title {
  font-size: 17px;
  font-weight: 700;
}

.feedback-text {
  margin-top: 8px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.feedback-text + .feedback-text {
  margin-top: 10px;
}

/* ============ pages: channels ============ */

.page-aside,
.page-sidebar {
  min-width: 0;
  position: sticky;
  top: 88px;
}

.aside-title,
.sidebar-title {
  font-size: 14px;
  font-weight: 700;
  color: var(--ink);
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 10px;
}

.aside-title + .aside-nav,
.aside-nav + .aside-title {
  margin-top: 22px;
}

.aside-list li,
.sidebar-list li {
  margin-bottom: 2px;
}

.aside-list a,
.sidebar-list a {
  display: block;
  padding: 7px 10px;
  min-height: 38px;
  font-size: 14px;
  line-height: 24px;
  color: var(--ink-soft);
  border-left: 2px solid transparent;
  border-bottom: none;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.aside-list a:hover,
.aside-list a:focus-visible,
.sidebar-list a:hover,
.sidebar-list a:focus-visible {
  color: var(--accent-deep);
  background-color: var(--bg-soft);
  border-left-color: var(--accent);
  border-bottom-color: transparent;
}

.aside-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.aside-tag a {
  display: inline-block;
  padding: 6px 10px;
  min-height: 34px;
  line-height: 22px;
  font-size: 13px;
  color: var(--ink-soft);
  background-color: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 999px;
  border-bottom: 1px solid var(--line);
}

.aside-tag a:hover,
.aside-tag a:focus-visible {
  color: var(--accent-deep);
  border-color: var(--accent);
}

.aside-note,
.sidebar-note {
  margin-top: 18px;
  font-size: 13px;
  line-height: 1.75;
  color: var(--ink-mute);
}

.aside-note-title {
  font-size: 13px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 8px;
}

.aside-link-list li {
  margin-bottom: 6px;
}

.aside-link-list a {
  font-size: 13px;
}

.channel-item {
  display: grid;
  grid-template-columns: minmax(0, 260px) minmax(0, 1fr);
  gap: 22px;
  align-items: start;
  padding: 20px 0;
  border-bottom: 1px solid var(--line);
}

.channel-item:first-of-type {
  padding-top: 4px;
}

.channel-media {
  aspect-ratio: 4 / 3;
  display: flex;
  flex-direction: column;
}

.channel-media img {
  flex: 1 1 auto;
  min-height: 0;
}

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

.channel-body .channel-name {
  font-size: 18px;
  font-weight: 700;
}

.channel-def {
  margin-top: 8px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink);
}

.channel-text {
  margin-top: 8px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.channel-for {
  margin-top: 10px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-mute);
}

.compare-table {
  margin-top: 4px;
}

.scope-columns,
.boundary-columns {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  margin-top: 4px;
}

.scope-col,
.boundary-col {
  min-width: 0;
  padding: 18px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.scope-title,
.boundary-title {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 10px;
}

.scope-in .scope-title,
.boundary-in .boundary-title {
  color: var(--accent-deep);
}

.scope-out .scope-title,
.boundary-out .boundary-title {
  color: var(--warm);
}

.scope-list li,
.boundary-list li {
  position: relative;
  padding-left: 16px;
  margin-bottom: 8px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.scope-list li::before,
.boundary-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background-color: var(--line-strong);
}

.scope-in .scope-list li::before,
.boundary-in .boundary-list li::before {
  background-color: var(--accent);
}

.scope-out .scope-list li::before,
.boundary-out .boundary-list li::before {
  background-color: var(--warm);
}

/* ============ pages: collections ============ */

.section-collections .collection-item {
  display: grid;
  grid-template-columns: minmax(0, 240px) minmax(0, 1fr);
  gap: 22px;
  align-items: start;
  padding: 20px 0;
  border-bottom: 1px solid var(--line);
}

.section-collections .collection-item:first-of-type {
  padding-top: 4px;
}

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

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

.collection-body .collection-name {
  font-size: 18px;
  font-weight: 700;
}

.collection-scope {
  margin-top: 8px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.collection-body .collection-channel {
  margin-top: 8px;
  font-size: 14px;
  color: var(--ink-mute);
}

.collection-term {
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px dashed var(--line);
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.organize-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  margin-top: 4px;
}

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

.organize-title {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--accent-deep);
}

.organize-list li {
  position: relative;
  padding-left: 16px;
  margin-bottom: 8px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.organize-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background-color: var(--accent);
}

.section-entry .step-body .step-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
}

/* ============ pages: fields ============ */

.content-section {
  margin-bottom: 44px;
}

.content-figure {
  margin: 16px 0 24px;
  aspect-ratio: 16 / 7;
  display: flex;
  flex-direction: column;
}

.content-figure img {
  flex: 1 1 auto;
  min-height: 0;
}

.field-card {
  padding: 18px;
  margin-bottom: 14px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius);
}

.field-card .field-name {
  font-size: 17px;
  font-weight: 700;
}

.field-definition {
  margin-top: 8px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink);
}

.field-body {
  margin-top: 8px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.decision-example {
  margin-top: 4px;
  padding: 20px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.decision-lead {
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink);
}

.decision-steps {
  margin-top: 12px;
  display: grid;
  gap: 10px;
}

.decision-step {
  position: relative;
  padding-left: 34px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.decision-step .step-label {
  position: absolute;
  left: 0;
  top: 2px;
  min-width: 24px;
  height: 24px;
  line-height: 24px;
  text-align: center;
  font-size: 12px;
  font-weight: 700;
  color: var(--accent-deep);
  background-color: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
}

.decision-tail {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
}

/* ============ pages: guide ============ */

.guide-steps,
.guide-filter,
.guide-field-points,
.guide-faq,
.guide-feedback {
  margin-bottom: 44px;
}

.guide-figure {
  margin: 16px 0 24px;
  aspect-ratio: 16 / 7;
  display: flex;
  flex-direction: column;
}

.guide-figure img {
  flex: 1 1 auto;
  min-height: 0;
}

.guide-steps .step-item {
  padding-left: 18px;
}

.filter-block,
.filter-example {
  padding: 18px;
  margin-bottom: 14px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.filter-example {
  background-color: var(--bg-soft);
}

.filter-title {
  font-size: 16px;
  font-weight: 700;
}

.filter-text {
  margin-top: 8px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.faq-list {
  border-top: 1px solid var(--line);
}

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

.faq-question {
  display: block;
  padding: 14px 40px 14px 0;
  min-height: 44px;
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
  cursor: pointer;
  position: relative;
  list-style: none;
}

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

.faq-question::after {
  content: "";
  position: absolute;
  right: 12px;
  top: 22px;
  width: 8px;
  height: 8px;
  border-right: 2px solid var(--accent);
  border-bottom: 2px solid var(--accent);
  transform: rotate(45deg);
  transition: transform 0.18s ease;
}

.faq-item[open] .faq-question::after {
  transform: rotate(-135deg);
}

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

.faq-answer {
  padding: 0 0 16px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
  max-width: 68ch;
}

.guide-feedback .feedback-text {
  margin-top: 10px;
}

/* ============ pages: 404 ============ */

.error-main {
  max-width: var(--width-shell);
  margin: 0 auto;
  padding: 56px 24px 64px;
}

.error-hero {
  padding: 32px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.error-code {
  font-size: 13px;
  font-weight: 700;
  color: var(--warm);
}

.error-hero h1 {
  margin-top: 10px;
  font-size: 28px;
  font-weight: 700;
}

.error-text {
  margin-top: 12px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
  max-width: 60ch;
}

.error-actions {
  margin-top: 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.error-links {
  margin-top: 32px;
}

.error-links h2 {
  font-size: 20px;
  font-weight: 700;
}

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

.error-link-list a {
  display: block;
  padding: 16px;
  min-height: 44px;
  font-size: 15px;
  color: var(--ink);
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  border-bottom: 1px solid var(--line);
}

.error-link-list a:hover,
.error-link-list a:focus-visible {
  border-color: var(--accent);
  color: var(--accent-deep);
}

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

@media (max-width: 1024px) {
  .home-hero {
    grid-template-columns: minmax(0, 1fr);
  }

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

  .channel-row {
    grid-template-columns: minmax(120px, 170px) minmax(0, 1fr);
  }

  .channel-fit {
    grid-column: 2 / -1;
  }
}

@media (max-width: 900px) {
  .page-layout,
  .page-layout.sidebar-left,
  .sidebar-left .page-layout {
    grid-template-columns: minmax(0, 1fr);
    gap: 28px;
  }

  .page-aside,
  .page-sidebar {
    position: static;
    order: 2;
    padding: 16px;
    background-color: var(--bg-surface);
    border: 1px solid var(--line);
    border-radius: var(--radius);
  }

  .page-content {
    order: 1;
    max-width: none;
  }

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

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

  .error-link-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 768px) {
  .header-inner {
    padding: 12px 16px;
    gap: 12px;
  }

  .nav-toggle {
    display: block;
  }

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

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding: 8px 0 4px;
    border-top: 1px solid var(--line);
  }

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

  .nav-link {
    padding: 11px 12px;
    font-size: 16px;
  }

  .home-main,
  .inner-main,
  .error-main {
    padding: 20px 16px 48px;
  }

  .hero-title {
    font-size: 25px;
  }

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

  .section-title {
    font-size: 19px;
  }

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

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

  .channel-fit {
    grid-column: auto;
  }

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

  .channel-item,
  .section-collections .collection-item {
    grid-template-columns: minmax(0, 1fr);
    gap: 14px;
  }

  .scope-columns,
  .boundary-columns,
  .organize-grid {
    grid-template-columns: minmax(0, 1fr);
  }

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

  .footer-inner {
    padding: 28px 16px 20px;
  }

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

  .footer-copy {
    padding: 14px 16px 24px;
  }

  .error-hero {
    padding: 22px;
  }

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

  .data-table,
  .field-table,
  .compare-table {
    font-size: 13px;
  }

  .data-table th,
  .data-table td,
  .field-table th,
  .field-table td,
  .compare-table th,
  .compare-table td {
    padding: 9px 10px;
  }
}

@media (max-width: 480px) {
  .site-body {
    font-size: 15px;
  }

  .hero-title {
    font-size: 22px;
  }

  .page-title {
    font-size: 22px;
  }

  .step-item,
  .path-step {
    padding: 14px 14px 14px 50px;
  }

  .step-index {
    left: 12px;
    top: 14px;
  }
}