:root {
  --paper: #f4f2ec;
  --ink: #2b2f2c;
  --ink-soft: #6b7069;
  --green: #2f4a3e;
  --green-soft: #3d5c4d;
  --ochre: #a8622a;
  --line: #d8d4c8;
  --card: #ffffff;
  --serif: "Songti SC", "SimSun", "Source Han Serif SC", "Noto Serif CJK SC", Georgia, serif;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  --wrap: 1120px;
  --radius: 6px;
  --shadow: 0 1px 0 rgba(47, 74, 62, 0.06);
}

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

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

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

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.75;
  font-weight: 400;
}

h1,
h2,
h3,
h4 {
  font-family: var(--serif);
  font-weight: 600;
  line-height: 1.3;
  color: var(--green);
  margin: 0;
}

p {
  margin: 0;
}

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

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

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

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

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

button {
  font-family: inherit;
  font-size: inherit;
  cursor: pointer;
}

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

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

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

.site-main {
  flex: 1 0 auto;
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 20px 56px;
}

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

.top-notice {
  background: var(--green);
  color: #eef1ec;
}

.top-notice-text {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 9px 20px;
  font-size: 13px;
  line-height: 1.6;
  letter-spacing: 0.01em;
}

.section {
  margin-top: 52px;
}

.section-head {
  border-bottom: 1px solid var(--line);
  padding-bottom: 14px;
  margin-bottom: 22px;
}

.section-title {
  font-size: 22px;
  color: var(--green);
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.section-title::before {
  content: "";
  width: 4px;
  height: 16px;
  background: var(--ochre);
  display: inline-block;
  flex: none;
  transform: translateY(-1px);
}

.section-desc,
.section-lead,
.section-intro {
  margin-top: 8px;
  color: var(--ink-soft);
  font-size: 14.5px;
  max-width: 860px;
}

.section-more,
.section-foot,
.section-footnote {
  margin-top: 18px;
  font-size: 14px;
  color: var(--ink-soft);
}

.text-link,
.inline-link {
  color: var(--green);
  border-bottom: 1px solid var(--line);
  padding-bottom: 1px;
  margin-right: 16px;
  display: inline-block;
}

.text-link:hover,
.inline-link:hover {
  border-bottom-color: var(--ochre);
  color: var(--ochre);
}

/* ============ header / nav ============ */

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

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

.brand {
  display: flex;
  align-items: baseline;
  gap: 12px;
  min-width: 0;
}

.brand-mark {
  font-family: var(--serif);
  font-size: 20px;
  font-weight: 600;
  color: var(--green);
  letter-spacing: 0.02em;
}

.brand-slogan {
  font-size: 13px;
  color: var(--ink-soft);
  border-left: 1px solid var(--line);
  padding-left: 12px;
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  padding: 0;
}

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

.site-nav {
  min-width: 0;
}

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

.nav-item {
  flex: none;
}

.nav-link {
  display: block;
  padding: 8px 14px;
  font-size: 15px;
  color: var(--ink);
  border-bottom: 2px solid transparent;
  transition: color 0.18s ease, border-color 0.18s ease;
}

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

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

/* ============ breadcrumb / page header ============ */

.breadcrumb {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 18px 20px 0;
  font-size: 13.5px;
  color: var(--ink-soft);
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

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

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

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

.breadcrumb-current {
  color: var(--green);
  font-weight: 600;
}

.page-header {
  padding: 22px 0 20px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 34px;
}

.page-description {
  font-family: var(--mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--ochre);
  text-transform: uppercase;
  margin-bottom: 10px;
}

.page-title {
  font-size: 32px;
  color: var(--green);
  line-height: 1.3;
}

.page-intro,
.page-lead {
  margin-top: 12px;
  color: var(--ink-soft);
  font-size: 15px;
  max-width: 860px;
}

/* ============ figure ============ */

.hero-figure,
.topic-media,
.topic-cover,
.page-figure,
.guide-figure,
.record-figure {
  margin: 0;
  overflow: hidden;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--card);
}

.hero-figure img,
.topic-media img,
.topic-cover img,
.page-figure img,
.guide-figure img,
.record-figure img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

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

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

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

.hero-caption,
.page-figure-caption,
.guide-figure-caption,
.record-figure-caption {
  padding: 10px 14px;
  font-size: 13px;
  color: var(--ink-soft);
  border-top: 1px solid var(--line);
  background: var(--paper);
}

/* ============ tables ============ */

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

.data-table {
  min-width: 720px;
  font-size: 14.5px;
}

.table-caption {
  caption-side: top;
  text-align: left;
  padding: 14px 16px;
  font-family: var(--mono);
  font-size: 12.5px;
  letter-spacing: 0.05em;
  color: var(--ink-soft);
  border-bottom: 1px solid var(--line);
  background: var(--paper);
}

.data-table thead th {
  text-align: left;
  padding: 12px 16px;
  background: var(--paper);
  color: var(--green);
  font-weight: 600;
  font-size: 13.5px;
  border-bottom: 1px solid var(--line);
  white-space: nowrap;
}

.data-table tbody td {
  padding: 13px 16px;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
  color: var(--ink);
}

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

.table-row:hover td {
  background: #faf8f3;
}

.cell-code {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--ochre);
  white-space: nowrap;
}

.cell-name {
  font-weight: 600;
  color: var(--green);
}

.field-table {
  min-width: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
}

.field-table tbody th {
  text-align: left;
  width: 34%;
  padding: 12px 16px;
  border-bottom: 1px solid var(--line);
  font-weight: 600;
  color: var(--green);
  font-size: 14px;
  vertical-align: top;
}

.field-table tbody td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 14px;
}

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

/* ============ home hero ============ */

.hero {
  padding: 44px 0 0;
}

.hero-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: 40px;
  align-items: start;
}

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

.hero-kicker {
  font-family: var(--mono);
  font-size: 12.5px;
  letter-spacing: 0.08em;
  color: var(--ochre);
  margin-bottom: 12px;
}

.hero-title {
  font-size: 34px;
  line-height: 1.28;
  color: var(--green);
}

.hero-desc {
  margin-top: 16px;
  color: var(--ink-soft);
  font-size: 15.5px;
  max-width: 560px;
}

.hero-points {
  margin-top: 20px;
  display: grid;
  gap: 8px;
}

.hero-point {
  position: relative;
  padding-left: 20px;
  font-size: 14.5px;
  color: var(--ink);
}

.hero-point::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 8px;
  height: 8px;
  border: 1px solid var(--ochre);
  background: transparent;
}

.hero-actions {
  margin-top: 26px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 22px;
  border-radius: var(--radius);
  font-size: 15px;
  border: 1px solid transparent;
  transition: background 0.18s ease, color 0.18s ease, border-color 0.18s ease;
}

.btn-primary {
  background: var(--green);
  color: #f4f2ec;
  border-color: var(--green);
}

.btn-primary:hover {
  background: var(--green-soft);
  color: #ffffff;
}

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

.btn-ghost:hover {
  border-color: var(--ochre);
  color: var(--ochre);
}

.hero-flow {
  margin-top: 40px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
  padding: 20px 22px;
}

.hero-flow-title {
  font-family: var(--mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--ink-soft);
  margin-bottom: 14px;
}

.flow-list {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.flow-item {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding-top: 12px;
  border-top: 2px solid var(--green);
  min-width: 0;
}

.flow-step {
  font-family: var(--mono);
  font-size: 12.5px;
  color: var(--ochre);
  flex: none;
}

.flow-text {
  font-size: 14px;
  color: var(--ink);
}

/* ============ channel table rows ============ */

.channel-table-section .section-head,
.channel-field-section .section-head,
.channel-topic-section .section-head {
  margin-bottom: 20px;
}

/* ============ topic cards ============ */

.topic-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
}

.topic-card {
  display: flex;
  flex-direction: column;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.topic-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 18px rgba(47, 74, 62, 0.08);
}

.topic-media,
.topic-cover {
  border: none;
  border-radius: 0;
  border-bottom: 1px solid var(--line);
}

.topic-media img,
.topic-cover img {
  aspect-ratio: 16 / 9;
}

.topic-body {
  padding: 16px 18px 18px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-width: 0;
}

.topic-code,
.topic-index {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--ochre);
}

.topic-name {
  font-size: 17px;
  color: var(--green);
}

.topic-link {
  color: var(--green);
}

.topic-link:hover {
  color: var(--ochre);
}

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

.topic-meta {
  font-size: 13px;
  color: var(--ink-soft);
  border-top: 1px dashed var(--line);
  padding-top: 10px;
  margin: 0;
}

.topic-meta dt {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--ochre);
  display: inline;
}

.topic-meta dd {
  display: inline;
  margin: 0;
}

.topic-meta dt + dd::before {
  content: " · ";
  color: var(--line);
}

/* ============ record ============ */

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

.record-group {
  background: var(--card);
  border: 1px solid var(--line);
  border-left: 3px solid var(--green);
  border-radius: var(--radius);
  padding: 16px 18px;
  min-width: 0;
}

.record-month {
  font-size: 16px;
  color: var(--green);
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.record-list {
  display: grid;
  gap: 10px;
}

.record-item {
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-areas:
    "date scope"
    "date type";
  gap: 2px 12px;
  font-size: 13.5px;
  min-width: 0;
}

.record-date {
  grid-area: date;
  font-family: var(--mono);
  font-size: 12.5px;
  color: var(--ochre);
  white-space: nowrap;
}

.record-scope {
  grid-area: scope;
  color: var(--ink);
}

.record-type {
  grid-area: type;
  color: var(--ink-soft);
  font-size: 13px;
}

/* ============ guide cols ============ */

.guide-cols {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 26px;
}

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

.guide-subtitle {
  font-size: 16px;
  color: var(--green);
  margin-bottom: 12px;
}

.guide-note {
  font-size: 13px;
  color: var(--ink-soft);
  margin-top: 12px;
}

/* ============ index grid ============ */

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

.index-col {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  min-width: 0;
}

.index-heading {
  font-size: 16px;
  color: var(--green);
}

.index-text {
  font-size: 13.5px;
  color: var(--ink-soft);
  flex: 1 1 auto;
}

.index-link {
  font-size: 14px;
  color: var(--ochre);
  border-bottom: 1px solid var(--line);
  align-self: flex-start;
  padding-bottom: 2px;
}

.index-link:hover {
  color: var(--green);
  border-bottom-color: var(--green);
}

/* ============ inner page: channel ============ */

.field-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
  gap: 26px;
}

.field-column {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 20px;
  min-width: 0;
}

.subsection-title {
  font-size: 16px;
  color: var(--green);
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.field-name-list,
.field-meaning-list {
  display: grid;
  gap: 10px;
}

.field-name-item {
  font-family: var(--mono);
  font-size: 13.5px;
  color: var(--ochre);
  padding: 8px 12px;
  background: var(--paper);
  border-left: 3px solid var(--green);
  border-radius: 0 var(--radius) var(--radius) 0;
}

.field-meaning-item {
  font-size: 14px;
  color: var(--ink-soft);
  padding: 8px 0;
  border-bottom: 1px dashed var(--line);
}

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

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

.correspond-column {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 20px;
  min-width: 0;
}

.correspond-list {
  display: grid;
  gap: 10px;
}

.correspond-item {
  font-size: 14px;
  color: var(--ink);
  padding: 9px 12px;
  background: var(--paper);
  border-radius: var(--radius);
  border-left: 3px solid var(--ochre);
}

/* ============ inner page: topic ============ */

.section-topic-list .section-title,
.section-topic-idea .section-title,
.section-topic-scope .section-title {
  font-size: 22px;
}

.section-topic-list .section-lead,
.section-topic-idea .section-lead,
.section-topic-scope .section-lead {
  margin-bottom: 22px;
}

.idea-pairs {
  display: grid;
  gap: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
  overflow: hidden;
}

.idea-row {
  display: grid;
  grid-template-columns: minmax(0, 0.7fr) minmax(0, 1.3fr);
  gap: 20px;
  padding: 14px 18px;
  border-bottom: 1px solid var(--line);
}

.idea-row:last-child {
  border-bottom: none;
}

.idea-row:hover {
  background: #faf8f3;
}

.idea-name {
  font-family: var(--serif);
  font-size: 15px;
  font-weight: 600;
  color: var(--green);
}

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

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

.scope-item {
  background: var(--card);
  border: 1px solid var(--line);
  border-top: 3px solid var(--ochre);
  border-radius: var(--radius);
  padding: 16px 18px;
  min-width: 0;
}

.scope-title {
  font-size: 15.5px;
  color: var(--green);
  margin-bottom: 8px;
}

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

/* ============ inner page: guide ============ */

.guide-section {
  margin-top: 44px;
}

.guide-section .section-title {
  font-size: 22px;
  margin-bottom: 8px;
}

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

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

.boundary-col {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 20px;
  min-width: 0;
}

.boundary-subtitle {
  font-size: 16px;
  color: var(--green);
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.boundary-list {
  display: grid;
  gap: 10px;
}

.boundary-item {
  position: relative;
  padding-left: 18px;
  font-size: 14px;
  color: var(--ink-soft);
}

.boundary-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 7px;
  height: 7px;
  background: var(--ochre);
  border-radius: 1px;
}

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

.faq-list {
  display: grid;
  gap: 12px;
}

.faq-item {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0;
  overflow: hidden;
}

.faq-question {
  list-style: none;
  cursor: pointer;
  padding: 15px 46px 15px 18px;
  font-family: var(--serif);
  font-size: 15.5px;
  font-weight: 600;
  color: var(--green);
  position: relative;
  min-height: 44px;
  display: flex;
  align-items: center;
}

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

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

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

.faq-answer {
  padding: 0 18px 16px;
  font-size: 14px;
  color: var(--ink-soft);
  border-top: 1px solid var(--line);
  padding-top: 14px;
  margin-top: 0;
}

.next-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.next-item {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-width: 0;
}

.next-link {
  font-family: var(--serif);
  font-size: 15.5px;
  font-weight: 600;
  color: var(--green);
}

.next-link:hover {
  color: var(--ochre);
}

.next-desc {
  font-size: 13.5px;
  color: var(--ink-soft);
}

/* ============ inner page: record ============ */

.record-months .section-head,
.record-notes .section-head,
.record-links .section-head {
  margin-bottom: 20px;
}

.record-details {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
  margin-bottom: 14px;
  overflow: hidden;
}

.record-summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 18px;
  min-height: 44px;
  background: var(--paper);
  border-bottom: 1px solid transparent;
}

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

.record-details[open] .record-summary {
  border-bottom-color: var(--line);
}

.record-details .record-month {
  font-size: 16px;
  color: var(--green);
  margin: 0;
  padding: 0;
  border: none;
}

.record-count {
  font-family: var(--mono);
  font-size: 12.5px;
  color: var(--ochre);
  white-space: nowrap;
}

.record-details .record-list {
  padding: 14px 18px;
}

.record-row {
  display: grid;
  grid-template-columns: 110px minmax(0, 1fr) 140px;
  gap: 14px;
  padding: 9px 0;
  border-bottom: 1px dashed var(--line);
  font-size: 14px;
  min-width: 0;
}

.record-row:last-child {
  border-bottom: none;
}

.record-channel {
  color: var(--ink);
}

.notes-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
}

.notes-item {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px 18px;
  min-width: 0;
}

.notes-heading {
  font-size: 15.5px;
  color: var(--green);
  margin-bottom: 8px;
}

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

.link-table {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
  overflow: hidden;
}

.link-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr) minmax(0, 1fr);
  gap: 14px;
  padding: 12px 18px;
  border-bottom: 1px solid var(--line);
  font-size: 14px;
}

.link-row:last-child {
  border-bottom: none;
}

.link-row-head {
  background: var(--paper);
  font-weight: 600;
  color: var(--green);
  font-size: 13.5px;
}

.link-cell {
  min-width: 0;
  color: var(--ink);
}

.link-row-head .link-cell {
  color: var(--green);
}

.record-footnote {
  margin-top: 16px;
  font-size: 14px;
  color: var(--ink-soft);
}

/* ============ 404 ============ */

.error-main {
  padding-top: 48px;
}

.error-block {
  max-width: 640px;
  background: var(--card);
  border: 1px solid var(--line);
  border-top: 4px solid var(--ochre);
  border-radius: var(--radius);
  padding: 32px 30px;
}

.error-code {
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--ochre);
  margin-bottom: 10px;
}

.error-title {
  font-size: 30px;
  color: var(--green);
  margin-bottom: 12px;
}

.error-text {
  font-size: 15px;
  color: var(--ink-soft);
  margin-bottom: 22px;
}

.error-actions {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.error-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
  color: var(--green);
  font-size: 14.5px;
  text-align: center;
}

.error-btn:hover {
  border-color: var(--ochre);
  color: var(--ochre);
}

.error-hint {
  margin-top: 34px;
}

.error-hint-title {
  font-size: 18px;
  color: var(--green);
  margin-bottom: 14px;
}

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

.error-hint-list li {
  font-size: 14px;
  color: var(--ink-soft);
  padding-left: 18px;
  position: relative;
}

.error-hint-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 7px;
  height: 7px;
  background: var(--green);
  border-radius: 1px;
}

/* ============ footer ============ */

.site-footer {
  background: var(--green);
  color: #dfe5df;
  margin-top: 40px;
  flex: none;
}

.footer-inner {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 44px 20px 26px;
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) repeat(3, minmax(0, 1fr)) minmax(0, 1.2fr);
  gap: 28px;
}

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

.footer-name {
  font-family: var(--serif);
  font-size: 18px;
  font-weight: 600;
  color: #ffffff;
  margin-bottom: 10px;
}

.footer-desc {
  font-size: 13.5px;
  line-height: 1.7;
  color: #c3cec6;
}

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

.footer-heading {
  font-family: var(--mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: #9fb3a6;
  margin-bottom: 12px;
  font-weight: 600;
}

.footer-list {
  display: grid;
  gap: 8px;
}

.footer-link {
  color: #dfe5df;
  font-size: 14px;
}

.footer-link:hover {
  color: #ffffff;
  text-decoration: underline;
}

.footer-note {
  font-size: 13px;
  color: #c3cec6;
  line-height: 1.7;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.16);
}

.footer-copy {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 16px 20px 22px;
  font-size: 13px;
  color: #b6c4ba;
}

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

@media (max-width: 960px) {
  .header-inner {
    flex-wrap: wrap;
    align-items: center;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    width: 100%;
    order: 3;
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    border-top: 1px solid var(--line);
    margin-top: 12px;
  }

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

  .nav-link {
    padding: 13px 4px;
    border-bottom: 1px solid var(--line);
    min-height: 44px;
    display: flex;
    align-items: center;
  }

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

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

  .hero-title {
    font-size: 28px;
  }

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

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

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

  .guide-cols {
    grid-template-columns: minmax(0, 1fr);
    gap: 22px;
  }

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

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

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

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

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

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

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

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

  .record-row {
    grid-template-columns: 100px minmax(0, 1fr);
    grid-template-areas:
      "date channel"
      "date type";
    gap: 2px 14px;
  }

  .record-row .record-date {
    grid-area: date;
  }

  .record-row .record-channel {
    grid-area: channel;
  }

  .record-row .record-type {
    grid-area: type;
    color: var(--ink-soft);
    font-size: 13px;
  }

  .footer-inner {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 26px;
  }

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

@media (max-width: 640px) {
  .site-main {
    padding: 0 16px 44px;
  }

  .top-notice-text,
  .header-inner,
  .breadcrumb,
  .footer-inner,
  .footer-copy {
    padding-left: 16px;
    padding-right: 16px;
  }

  .brand {
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
  }

  .brand-slogan {
    border-left: none;
    padding-left: 0;
    font-size: 12.5px;
  }

  .hero {
    padding-top: 30px;
  }

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

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

  .section {
    margin-top: 40px;
  }

  .section-title,
  .guide-section .section-title,
  .section-topic-list .section-title,
  .section-topic-idea .section-title,
  .section-topic-scope .section-title {
    font-size: 19px;
  }

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

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

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

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

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

  .data-table {
    min-width: 0;
  }

  .table-wrap {
    overflow-x: visible;
    border: none;
    background: transparent;
  }

  .data-table thead {
    display: none;
  }

  .data-table,
  .data-table tbody,
  .data-table tr,
  .data-table td {
    display: block;
    width: 100%;
  }

  .data-table tbody tr {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 6px 0;
    margin-bottom: 14px;
  }

  .data-table tbody td {
    border-bottom: 1px dashed var(--line);
    padding: 9px 14px;
  }

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

  .channel-table tbody td::before {
    content: attr(data-label);
    display: block;
    font-family: var(--mono);
    font-size: 11.5px;
    letter-spacing: 0.05em;
    color: var(--ochre);
    margin-bottom: 3px;
  }

  .channel-table .cell-code,
  .channel-table .cell-name {
    font-size: 15px;
  }

  .field-table {
    border: none;
    background: transparent;
  }

  .field-table tbody th,
  .field-table tbody td {
    display: block;
    width: 100%;
    border: none;
    padding: 0;
  }

  .field-table tbody tr {
    display: block;
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 12px 14px;
    margin-bottom: 12px;
  }

  .field-table tbody th {
    color: var(--green);
    margin-bottom: 4px;
  }

  .field-table tbody tr:last-child {
    margin-bottom: 0;
  }

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

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

  .link-row-head {
    display: none;
  }

  .link-row .link-cell {
    padding: 2px 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .topic-card,
  .nav-link,
  a,
  .btn {
    transition: none;
  }

  .topic-card:hover {
    transform: none;
  }
}