:root {
  --ink: #2f4f4f;
  --ink-soft: #3d5c5c;
  --link: #4a7c7c;
  --link-strong: #35625f;
  --accent: #c25e3a;
  --bg: #f7f7f5;
  --surface: #ffffff;
  --line: #e0e0dc;
  --line-strong: #cfcfc9;
  --muted: #6b7876;
  --mono: "SFMono-Regular", "Consolas", "Liberation Mono", "Menlo", monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", sans-serif;
  --radius: 6px;
  --shell: 1080px;
  --main-col: 720px;
  --side-col: 320px;
}

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

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

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

body.site-body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.8;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4 {
  margin: 0;
  color: var(--ink);
  font-weight: 600;
  line-height: 1.4;
}

p {
  margin: 0;
}

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

dl {
  margin: 0;
}

dt,
dd {
  margin: 0;
}

a {
  color: var(--link);
  text-decoration: none;
  transition: color 0.18s ease, border-color 0.18s ease;
}

a:hover,
a:focus-visible {
  color: var(--link-strong);
}

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

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

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
}

time,
.batch-code,
.update-code,
.rank-no,
.step-index {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 30;
  background: var(--surface);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 24px;
  min-height: 62px;
  display: flex;
  align-items: center;
  gap: 24px;
}

.brand {
  display: inline-flex;
  flex-direction: column;
  gap: 1px;
  padding: 10px 0;
  color: var(--ink);
  font-size: 19px;
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: 0;
}

.brand:hover,
.brand:focus-visible {
  color: var(--ink);
}

.brand-sub {
  color: var(--muted);
  font-size: 12px;
  font-weight: 400;
  line-height: 1.3;
}

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

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

.nav-list li {
  display: block;
}

.nav-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 12px;
  color: var(--ink-soft);
  font-size: 15px;
  border-bottom: 2px solid transparent;
}

.nav-link:hover,
.nav-link:focus-visible {
  color: var(--link-strong);
  border-bottom-color: var(--line-strong);
}

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

.nav-toggle {
  display: none;
  margin-left: auto;
  width: 44px;
  height: 44px;
  padding: 11px 10px;
  flex-direction: column;
  justify-content: space-between;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.nav-toggle-bar {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--ink);
  border-radius: 1px;
}

.site-main {
  display: block;
}

.inner-main {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 28px 24px 56px;
}

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

.footer-top {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 40px 24px 28px;
  display: grid;
  grid-template-columns: minmax(180px, 1fr) minmax(180px, 1fr) minmax(280px, 1.4fr);
  gap: 32px;
}

.footer-title {
  margin-bottom: 12px;
  font-size: 15px;
  color: var(--ink);
}

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

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

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

.footer-about {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.85;
}

.footer-bottom {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 16px 24px 32px;
  border-top: 1px solid var(--line);
  display: flex;
  flex-wrap: wrap;
  gap: 8px 24px;
  justify-content: space-between;
}

.footer-boundary,
.footer-copy {
  color: var(--muted);
  font-size: 13px;
  line-height: 1.7;
}

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

.fact-bar {
  background: var(--ink);
  color: #eef2f1;
}

.fact-bar p {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 8px 24px;
  font-size: 13px;
  line-height: 1.6;
}

.section {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 44px 24px 0;
}

.section-head {
  margin-bottom: 22px;
  max-width: 760px;
}

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

.section-desc,
.section-intro,
.section-lead {
  margin-top: 8px;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.8;
}

.section-figure,
.page-figure,
.hero-figure,
.duo-figure,
.guide-figure {
  margin: 0;
}

.section-figure img,
.page-figure img,
.hero-figure img,
.duo-figure img,
.guide-figure img {
  width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.section-figure img {
  aspect-ratio: 1080 / 380;
}

figcaption,
.figure-caption {
  margin-top: 8px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.7;
}

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  min-height: 32px;
  color: var(--link);
  font-size: 14px;
  border-bottom: 1px solid var(--line-strong);
}

.text-link::after {
  content: "→";
  font-size: 13px;
}

.text-link:hover,
.text-link:focus-visible {
  color: var(--link-strong);
  border-bottom-color: var(--link-strong);
}

.field-label {
  display: block;
  color: var(--muted);
  font-size: 12px;
  letter-spacing: 0;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 18px;
  color: var(--muted);
  font-size: 13px;
}

.breadcrumb a {
  color: var(--muted);
  min-height: 24px;
  display: inline-flex;
  align-items: center;
}

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

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

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

.page-header {
  margin-bottom: 28px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--line);
  max-width: 760px;
}

.page-title {
  font-size: 32px;
  line-height: 1.35;
}

.page-description {
  margin-top: 10px;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.85;
}

.page-layout {
  display: grid;
  grid-template-columns: minmax(0, var(--main-col)) minmax(240px, var(--side-col));
  gap: 40px;
  align-items: start;
}

.main-column,
.layout-main,
.content-main {
  min-width: 0;
}

.sidebar,
.layout-sidebar,
.content-side {
  min-width: 0;
  position: sticky;
  top: 86px;
}

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

.sidebar-block + .sidebar-block,
.side-block + .side-block,
.sidebar > .sidebar-title + .sidebar-list + .sidebar-title,
.sidebar-note {
  margin-top: 22px;
}

.anchor-list a,
.sidebar-list a,
.sidebar-links a,
.toc-list a,
.side-link-list a {
  display: flex;
  align-items: center;
  min-height: 36px;
  color: var(--ink-soft);
  font-size: 14px;
  border-bottom: 1px dashed var(--line);
}

.anchor-list a:hover,
.sidebar-list a:hover,
.sidebar-links a:hover,
.toc-list a:hover,
.side-link-list a:hover,
.anchor-list a:focus-visible,
.sidebar-list a:focus-visible,
.sidebar-links a:focus-visible,
.toc-list a:focus-visible,
.side-link-list a:focus-visible {
  color: var(--link-strong);
  border-bottom-color: var(--link);
}

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

.sidebar-note-title,
.sidebar-note .sidebar-title {
  margin: 0 0 8px;
  padding: 0;
  font-size: 14px;
  border: 0;
}

.sidebar-note-text {
  color: var(--muted);
  font-size: 13px;
  line-height: 1.8;
}

.sidebar-link {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  margin-top: 10px;
  color: var(--link);
  font-size: 13px;
  border-bottom: 1px solid var(--line-strong);
}

.related-block,
.related-section {
  margin-top: 40px;
  padding-top: 28px;
  border-top: 1px solid var(--line);
}

.related-links,
.related-grid,
.return-links,
.return-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
  margin-top: 18px;
}

.related-link,
.related-card,
.return-link,
.return-card {
  display: block;
  padding: 16px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--ink);
}

.related-link:hover,
.related-card:hover,
.return-link:hover,
.return-card:hover,
.related-link:focus-visible,
.related-card:focus-visible,
.return-link:focus-visible,
.return-card:focus-visible {
  border-color: var(--link);
  color: var(--ink);
  transform: translateY(-2px);
}

.related-link,
.related-card,
.return-link,
.return-card {
  transition: border-color 0.18s ease, transform 0.18s ease;
}

.related-name,
.related-title,
.return-card-name {
  font-size: 16px;
  color: var(--ink);
}

.related-desc,
.return-card-desc {
  margin-top: 6px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.75;
}

.related-item {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
}

.related-list {
  margin-top: 16px;
}

/* ============ pages: index ============ */

.hero {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 40px 24px 0;
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
  gap: 40px;
  align-items: start;
}

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

.hero-eyebrow {
  color: var(--accent);
  font-size: 13px;
  font-family: var(--mono);
  letter-spacing: 0;
}

.hero-title {
  margin-top: 10px;
  font-size: 34px;
  line-height: 1.35;
}

.hero-lead {
  margin-top: 14px;
  max-width: 560px;
  color: var(--ink-soft);
  font-size: 16px;
  line-height: 1.85;
}

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 20px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  font-size: 15px;
  transition: background-color 0.18s ease, border-color 0.18s ease, color 0.18s ease;
}

.btn-primary {
  background: var(--ink);
  border-color: var(--ink);
  color: #f4f7f6;
}

.btn-primary:hover,
.btn-primary:focus-visible {
  background: var(--link-strong);
  border-color: var(--link-strong);
  color: #ffffff;
}

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

.btn-ghost:hover,
.btn-ghost:focus-visible {
  border-color: var(--link);
  color: var(--link-strong);
}

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

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

.hero-returning {
  min-width: 0;
  padding: 22px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.hero-returning-title {
  font-size: 18px;
}

.hero-returning-lead {
  margin-top: 8px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.8;
}

.quick-entry {
  display: block;
  margin-top: 14px;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--ink);
  transition: border-color 0.18s ease, transform 0.18s ease;
}

.quick-entry:hover,
.quick-entry:focus-visible {
  border-color: var(--link);
  color: var(--ink);
  transform: translateY(-2px);
}

.quick-entry-label {
  display: block;
  font-size: 15px;
  font-weight: 600;
}

.quick-entry-desc {
  display: block;
  margin-top: 4px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.7;
}

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

.direction-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 18px;
}

.direction-card {
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  display: flex;
  flex-direction: column;
}

.direction-name {
  font-size: 18px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.direction-scope,
.direction-sample,
.direction-summary {
  margin-top: 12px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.direction-sample {
  color: var(--muted);
}

.direction-card .text-link {
  margin-top: auto;
  padding-top: 14px;
  align-self: flex-start;
}

.duo-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
  gap: 32px;
  align-items: start;
}

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

.duo-subtitle {
  font-size: 18px;
}

.duo-note {
  margin-top: 8px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.8;
}

.duo-figure {
  margin-top: 16px;
}

.duo-figure img {
  aspect-ratio: 16 / 10;
}

.entry-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 14px;
  margin-top: 18px;
}

.entry-card {
  padding: 14px 16px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: border-color 0.18s ease, transform 0.18s ease;
}

.entry-card:hover {
  border-color: var(--line-strong);
  transform: translateY(-2px);
}

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

.entry-fields {
  margin-top: 10px;
  display: grid;
  gap: 6px;
}

.entry-fields dt {
  color: var(--muted);
  font-size: 12px;
}

.entry-fields dd {
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.7;
}

.duo-col-log .update-list {
  margin-top: 18px;
}

.update-list {
  display: grid;
  gap: 0;
}

.update-item {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 12px;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
  font-size: 14px;
}

.update-date {
  color: var(--muted);
  font-size: 13px;
}

.update-batch {
  color: var(--accent);
  font-size: 13px;
}

.update-entry {
  color: var(--ink);
}

.update-dir {
  color: var(--muted);
  font-size: 13px;
}

.duo-col-log .text-link {
  margin-top: 18px;
}

.fields-layout {
  display: grid;
  grid-template-columns: minmax(200px, 0.8fr) minmax(280px, 1.4fr);
  gap: 32px;
  align-items: start;
}

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

.fields-subtitle {
  font-size: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.field-name-list {
  margin-top: 14px;
  display: grid;
  gap: 10px;
}

.field-name-item {
  padding: 10px 14px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius);
  font-size: 14px;
  color: var(--ink);
}

.field-rule-list {
  margin-top: 14px;
  display: grid;
  gap: 14px;
}

.field-rule-list dt {
  font-size: 14px;
  font-weight: 600;
  color: var(--ink);
}

.field-rule-list dd {
  margin-top: 4px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.8;
}

.fields-col-rule .text-link {
  margin-top: 18px;
}

.step-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 18px;
  margin-top: 22px;
}

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

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

.step-title {
  font-size: 16px;
}

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

.feedback-note {
  margin-top: 26px;
  padding: 20px 22px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.feedback-title {
  font-size: 16px;
}

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

.feedback-note .text-link {
  margin-top: 12px;
}

.index-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 14px;
}

.index-card {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--ink);
  transition: border-color 0.18s ease, transform 0.18s ease;
}

.index-card:hover,
.index-card:focus-visible {
  border-color: var(--link);
  color: var(--ink);
  transform: translateY(-2px);
}

.index-name {
  font-size: 15px;
  font-weight: 600;
}

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

/* ============ pages: tixiang ============ */

.direction-block {
  padding: 24px 0;
  border-bottom: 1px solid var(--line);
}

.direction-block:first-of-type {
  padding-top: 8px;
}

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

.direction-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 12px;
  margin-top: 12px;
  font-size: 13px;
}

.meta-label {
  color: var(--muted);
}

.meta-value {
  color: var(--ink-soft);
}

.subsection-title {
  margin-top: 20px;
  font-size: 15px;
  color: var(--ink);
}

.entry-summary-list {
  margin-top: 12px;
  display: grid;
  gap: 10px;
}

.entry-summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
  padding: 12px 14px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.entry-summary .entry-name {
  font-size: 15px;
}

.entry-field {
  color: var(--muted);
  font-size: 13px;
}

/* ============ pages: gengxin ============ */

.batch-status-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 28px;
  margin-top: 16px;
  padding: 16px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.batch-status-item {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 10px;
  font-size: 14px;
}

.batch-label {
  color: var(--muted);
  font-size: 13px;
}

.batch-value {
  color: var(--ink);
}

.batch-code {
  color: var(--accent);
}

.batch-status-note {
  margin-top: 10px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.75;
}

.layout-main .page-figure {
  margin-top: 26px;
}

.update-list-section .update-list {
  margin-top: 18px;
}

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

.update-entry {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
  padding: 14px 0;
}

.update-code {
  color: var(--accent);
  font-size: 13px;
}

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

.update-direction {
  color: var(--muted);
  font-size: 13px;
}

.update-state {
  margin-left: auto;
  padding: 2px 10px;
  background: #eef3f2;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--ink-soft);
  font-size: 12px;
}

.batch-rule-section .rule-list {
  margin-top: 16px;
  display: grid;
  gap: 16px;
}

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

.rule-desc {
  margin-top: 4px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.8;
}

.rule-footnote {
  margin-top: 16px;
  color: var(--muted);
  font-size: 13px;
}

.related-grid {
  margin-top: 18px;
}

/* ============ pages: weici ============ */

.section-rank .section-figure {
  margin-top: 20px;
}

.rank-list {
  margin-top: 22px;
  counter-reset: none;
}

.rank-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.rank-no {
  flex: 0 0 46px;
  color: var(--accent);
  font-size: 15px;
  line-height: 1.7;
}

.rank-body {
  min-width: 0;
  flex: 1 1 auto;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 16px;
}

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

.rank-direction,
.rank-period {
  color: var(--muted);
  font-size: 13px;
}

.rank-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 14px;
  width: 100%;
}

.section-note {
  margin-top: 16px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.8;
}

.section-note a {
  border-bottom: 1px solid var(--line-strong);
}

.section-caliber .caliber-block {
  margin-top: 20px;
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.caliber-heading {
  font-size: 16px;
}

.caliber-text {
  margin-top: 8px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.8;
}

/* ============ pages: zhiyin ============ */

.guide-steps .guide-figure {
  margin-top: 18px;
}

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

.guide-steps .step-list {
  margin-top: 22px;
}

.guide-steps .step-item {
  display: flex;
  gap: 14px;
  align-items: flex-start;
}

.guide-steps .step-index {
  flex: 0 0 auto;
  margin: 0;
  padding: 2px 10px;
  background: #fbf0eb;
  border: 1px solid #edcdbe;
  border-radius: var(--radius);
}

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

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

.field-reading-item {
  padding: 16px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.field-reading-name {
  font-size: 15px;
}

.field-reading-item p {
  margin-top: 8px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.8;
}

.feedback-columns {
  margin-top: 20px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 18px;
}

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

.feedback-subtitle {
  font-size: 15px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line);
}

.feedback-list {
  margin-top: 12px;
  display: grid;
  gap: 8px;
}

.feedback-list li {
  position: relative;
  padding-left: 16px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.8;
}

.feedback-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
}

.feedback-guide .feedback-note {
  margin-top: 18px;
  padding: 0;
  background: none;
  border: 0;
}

/* ============ pages: shuoming ============ */

.content-section {
  margin-top: 36px;
}

.content-section:first-of-type {
  margin-top: 28px;
}

.table-wrap {
  margin-top: 18px;
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.field-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

.table-caption {
  padding: 12px 16px;
  text-align: left;
  color: var(--muted);
  font-size: 13px;
  border-bottom: 1px solid var(--line);
}

.field-table th,
.field-table td {
  padding: 12px 16px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--line);
  line-height: 1.75;
}

.field-table th {
  background: #f3f4f2;
  color: var(--ink);
  font-weight: 600;
  white-space: nowrap;
}

.field-table td:first-child {
  color: var(--ink);
  font-weight: 600;
  white-space: nowrap;
}

.field-table td {
  color: var(--ink-soft);
}

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

.direction-rule {
  margin-top: 18px;
  padding: 16px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-left: 3px solid var(--link);
  border-radius: var(--radius);
}

.rule-title {
  font-size: 15px;
}

.rule-text {
  margin-top: 8px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.8;
}

.boundary-columns {
  margin-top: 18px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 18px;
}

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

.boundary-title {
  font-size: 15px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line);
}

.boundary-col-in .boundary-title {
  border-bottom-color: var(--link);
}

.boundary-col-out .boundary-title {
  border-bottom-color: var(--accent);
}

.boundary-list {
  margin-top: 12px;
  display: grid;
  gap: 8px;
}

.boundary-list li {
  position: relative;
  padding-left: 16px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.8;
}

.boundary-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 6px;
  height: 6px;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
}

.boundary-col-in .boundary-list li::before {
  background: var(--link);
  border-color: var(--link);
}

.boundary-col-out .boundary-list li::before {
  background: var(--accent);
  border-color: var(--accent);
}

.section-return .return-grid {
  margin-top: 18px;
}

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

.error-main {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 64px 24px 72px;
}

.error-panel {
  max-width: 640px;
  padding: 32px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.error-code {
  color: var(--accent);
  font-size: 14px;
}

.error-title {
  margin-top: 10px;
  font-size: 26px;
}

.error-desc {
  margin-top: 12px;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.85;
}

.error-hint-list {
  margin-top: 22px;
  display: grid;
  gap: 10px;
}

.error-hint-list a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  padding: 0 14px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--ink-soft);
  font-size: 14px;
}

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

.error-home-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  margin-top: 24px;
  padding: 0 22px;
  background: var(--ink);
  border: 1px solid var(--ink);
  border-radius: var(--radius);
  color: #f4f7f6;
  font-size: 15px;
}

.error-home-link:hover,
.error-home-link:focus-visible {
  background: var(--link-strong);
  border-color: var(--link-strong);
  color: #ffffff;
}

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

@media (max-width: 900px) {
  .header-inner {
    flex-wrap: wrap;
    gap: 8px;
    padding: 0 18px;
  }

  .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;
    padding-bottom: 10px;
    border-top: 1px solid var(--line);
  }

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

  .nav-link {
    width: 100%;
    min-height: 48px;
    padding: 0 6px;
    border-bottom: 1px solid var(--line);
    border-left: 2px solid transparent;
  }

  .nav-link:hover,
  .nav-link:focus-visible {
    border-bottom-color: var(--line);
    border-left-color: var(--line-strong);
  }

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

  .hero,
  .duo-layout,
  .fields-layout,
  .page-layout {
    grid-template-columns: minmax(0, 1fr);
    gap: 28px;
  }

  .hero {
    padding-top: 28px;
  }

  .sidebar,
  .layout-sidebar,
  .content-side {
    position: static;
  }

  .footer-top {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px;
    padding: 32px 18px 24px;
  }

  .footer-col-about {
    grid-column: 1 / -1;
  }

  .footer-bottom {
    padding: 16px 18px 28px;
  }

  .section {
    padding: 34px 18px 0;
  }

  .inner-main {
    padding: 24px 18px 48px;
  }

  .fact-bar p {
    padding: 8px 18px;
  }
}

@media (max-width: 600px) {
  body.site-body {
    font-size: 15px;
    line-height: 1.75;
  }

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

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

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

  .direction-name,
  .duo-subtitle,
  .step-title,
  .caliber-heading,
  .related-name,
  .related-title,
  .return-card-name {
    font-size: 16px;
  }

  .subsection-title,
  .fields-subtitle,
  .feedback-title,
  .feedback-subtitle,
  .rule-title,
  .boundary-title,
  .field-reading-name {
    font-size: 15px;
  }

  .hero-actions .btn {
    flex: 1 1 100%;
  }

  .entry-grid,
  .direction-grid,
  .step-list,
  .field-reading-list,
  .feedback-columns,
  .boundary-columns,
  .related-links,
  .related-grid,
  .return-links,
  .return-grid,
  .index-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .rank-no {
    flex-basis: 38px;
  }

  .update-state {
    margin-left: 0;
  }

  .error-panel {
    padding: 24px 20px;
  }

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