:root {
  --bg: #faf9f6;
  --ink: #23262b;
  --ink-soft: #5b6068;
  --accent: #3f5a7a;
  --accent-soft: #6d84a0;
  --line: #dcd8d0;
  --line-soft: #ebe8e1;
  --card: #ffffff;
  --serif: "Songti SC", "STSong", "Noto Serif SC", "SimSun", Georgia, serif;
  --sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --wrap: 1120px;
  --read: 720px;
  --radius: 6px;
}

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

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

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.75;
}

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

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

a:hover,
a:focus-visible {
  color: var(--accent-soft);
  text-decoration: underline;
  text-underline-offset: 3px;
}

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

h1,
h2,
h3,
h4 {
  margin: 0;
  font-weight: 700;
  line-height: 1.3;
  color: var(--ink);
}

p {
  margin: 0 0 1em;
}

p:last-child {
  margin-bottom: 0;
}

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

dl,
dd {
  margin: 0;
}

sup {
  font-size: 0.7em;
  vertical-align: super;
  line-height: 0;
}

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

.site-body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--serif);
}

.site-main {
  flex: 1 1 auto;
  width: 100%;
}

.inner-main,
.home-main {
  width: 100%;
}

.header-inner,
.footer-inner,
.site-main > section,
.site-main > nav.breadcrumb,
.site-main > div.page-header,
.site-main > header.page-header {
  width: 100%;
  max-width: var(--wrap);
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(250, 249, 246, 0.94);
  border-bottom: 1px solid var(--line-soft);
  transition: background 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}

.site-header.is-solid {
  background: var(--bg);
  box-shadow: 0 1px 0 var(--line);
}

.site-home .site-header {
  background: transparent;
  border-bottom-color: transparent;
}

.site-home .site-header.is-solid {
  background: var(--bg);
  border-bottom-color: var(--line-soft);
  box-shadow: 0 1px 0 var(--line-soft);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 68px;
}

.brand {
  display: inline-flex;
  align-items: center;
  font-family: var(--serif);
  font-size: 21px;
  font-weight: 700;
  color: var(--ink);
  letter-spacing: 0.02em;
  padding: 8px 0;
}

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

.site-nav {
  display: flex;
  align-items: center;
}

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

.nav-list > li {
  display: block;
}

.nav-list a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 13px;
  font-family: var(--sans);
  font-size: 15px;
  color: var(--ink-soft);
  border-bottom: 2px solid transparent;
}

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

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

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 0 10px;
  background: transparent;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  cursor: pointer;
}

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

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

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-top: 26px;
  padding-bottom: 4px;
  font-family: var(--sans);
  font-size: 13px;
  color: var(--ink-soft);
}

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

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

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

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

.page-header {
  padding-top: 20px;
  padding-bottom: 28px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 40px;
}

.page-description {
  font-family: var(--sans);
  font-size: 13px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin-bottom: 10px;
}

.page-title {
  font-family: var(--serif);
  font-size: 40px;
  font-weight: 700;
  line-height: 1.24;
  color: var(--ink);
  max-width: var(--read);
}

.page-lead {
  margin-top: 14px;
  max-width: var(--read);
  font-size: 17px;
  color: var(--ink-soft);
}

/* ============ section head shared ============ */

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

.section-title {
  font-family: var(--serif);
  font-size: 25px;
  font-weight: 700;
  color: var(--ink);
}

.section-note,
.section-intro,
.section-desc,
.section-lead {
  margin-top: 8px;
  max-width: var(--read);
  font-size: 15px;
  color: var(--ink-soft);
}

.section-foot {
  margin-top: 22px;
  font-family: var(--sans);
  font-size: 14px;
  color: var(--ink-soft);
}

.section-foot a {
  margin-right: 18px;
}

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

.site-footer {
  margin-top: 72px;
  border-top: 1px solid var(--line);
  background: #f4f2ee;
  padding: 44px 0 0;
}

.footer-inner {
  display: grid;
  grid-template-columns: minmax(220px, 1.4fr) repeat(3, minmax(150px, 1fr));
  gap: 32px;
  padding-bottom: 32px;
}

.footer-brand {
  max-width: 320px;
}

.footer-name {
  font-family: var(--serif);
  font-size: 20px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 8px;
}

.footer-desc {
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.footer-title {
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin-bottom: 12px;
}

.footer-list li {
  margin-bottom: 4px;
}

.footer-list a {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  font-family: var(--sans);
  font-size: 14px;
  color: var(--ink-soft);
}

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

.footer-copy {
  margin: 0;
  padding: 18px 24px 26px;
  max-width: var(--wrap);
  margin-left: auto;
  margin-right: auto;
  border-top: 1px solid var(--line);
  font-family: var(--sans);
  font-size: 13px;
  color: var(--ink-soft);
}

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

/* 通用按钮式链接 */
.topic-link,
.covers-more a,
.updates-more a,
.ranking-more a,
.fields-more a,
.guide-tail a,
.rank-footnote a,
.rank-back a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  padding: 0 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
  font-family: var(--sans);
  font-size: 14px;
  color: var(--accent);
}

.topic-link:hover,
.covers-more a:hover,
.updates-more a:hover,
.ranking-more a:hover,
.fields-more a:hover,
.guide-tail a:hover,
.rank-footnote a:hover,
.rank-back a:hover,
.topic-link:focus-visible,
.covers-more a:focus-visible,
.updates-more a:focus-visible,
.ranking-more a:focus-visible,
.fields-more a:focus-visible,
.guide-tail a:focus-visible,
.rank-footnote a:focus-visible,
.rank-back a:focus-visible {
  border-color: var(--accent-soft);
  color: var(--accent);
  text-decoration: none;
}

/* figure 通用约束 */
.hero-figure img,
.topic-figure img,
.guide-figure img,
.rank-media img {
  width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: var(--radius);
  background: var(--line-soft);
}

figcaption {
  margin-top: 10px;
  font-family: var(--sans);
  font-size: 13px;
  color: var(--ink-soft);
}

/* ============ page: index ============ */

/* 首屏摘要区 */
.hero-summary {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: 48px;
  align-items: center;
  padding-top: 56px;
  padding-bottom: 56px;
}

.hero-kicker {
  font-family: var(--sans);
  font-size: 13px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 14px;
}

.hero-title {
  font-family: var(--serif);
  font-size: 42px;
  font-weight: 700;
  line-height: 1.22;
  color: var(--ink);
  margin-bottom: 18px;
}

.hero-lead {
  max-width: 520px;
  font-size: 17px;
  color: var(--ink-soft);
  margin-bottom: 26px;
}

.hero-paths {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.hero-path a {
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 172px;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
}

.hero-path a:hover,
.hero-path a:focus-visible {
  border-color: var(--accent-soft);
  text-decoration: none;
}

.hero-path-label {
  font-family: var(--sans);
  font-size: 15px;
  font-weight: 600;
  color: var(--accent);
}

.hero-path-desc {
  font-size: 13px;
  color: var(--ink-soft);
}

.hero-figure {
  margin: 0;
}

.hero-figure img {
  aspect-ratio: 4 / 3;
}

/* 题材方向总览 */
.topic-overview {
  padding-top: 44px;
  padding-bottom: 44px;
  border-top: 1px solid var(--line);
}

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

.topic-column {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 22px 20px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.topic-name {
  font-family: var(--serif);
  font-size: 19px;
  color: var(--ink);
}

.topic-trait,
.topic-entry {
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.topic-trait {
  padding-bottom: 10px;
  border-bottom: 1px dashed var(--line);
}

.topic-link {
  margin-top: auto;
  align-self: flex-start;
}

/* 封面条目与最近更新并列区 */
.covers-and-updates {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(280px, 1fr);
  gap: 44px;
  padding-top: 44px;
  padding-bottom: 44px;
  border-top: 1px solid var(--line);
}

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

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

.cover-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 12px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: border-color 0.18s ease, transform 0.18s ease;
}

.cover-card:hover {
  border-color: var(--accent-soft);
  transform: translateY(-2px);
}

.cover-figure {
  margin: 0;
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--line-soft);
}

.cover-figure img {
  width: 100%;
  aspect-ratio: 3 / 4;
  object-fit: cover;
}

.cover-title {
  font-family: var(--serif);
  font-size: 16px;
  line-height: 1.4;
  color: var(--ink);
}

.cover-meta {
  font-family: var(--sans);
  font-size: 12px;
  color: var(--ink-soft);
  margin: 0;
}

.covers-more,
.updates-more,
.ranking-more,
.fields-more {
  margin-top: 22px;
}

/* 更新侧栏 */
.updates-column {
  min-width: 0;
  display: flex;
  flex-direction: column;
  padding: 22px 22px 24px;
  background: #f4f2ee;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.update-group {
  padding: 14px 0;
  border-top: 1px solid var(--line-soft);
}

.update-group:first-of-type {
  border-top: 0;
  padding-top: 0;
}

.update-date {
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.05em;
  color: var(--accent);
  margin-bottom: 8px;
}

.update-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  grid-template-areas:
    "work range"
    "topic topic";
  gap: 2px 10px;
  padding: 7px 0;
  border-bottom: 1px dotted var(--line);
}

.update-item:last-child {
  border-bottom: 0;
}

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

.update-range {
  grid-area: range;
  font-family: var(--sans);
  font-size: 12px;
  color: var(--ink-soft);
  white-space: nowrap;
}

.update-topic {
  grid-area: topic;
  font-family: var(--sans);
  font-size: 12px;
  color: var(--ink-soft);
}

/* 人气榜单与条目字段口径摘要 */
.ranking-and-fields {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(280px, 1fr);
  gap: 44px;
  padding-top: 44px;
  padding-bottom: 44px;
  border-top: 1px solid var(--line);
}

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

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

.ranking-column .rank-item {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr) minmax(96px, auto);
  grid-template-areas:
    "no work topic"
    "no note note";
  gap: 2px 12px;
  align-items: baseline;
  padding: 13px 0;
  border-bottom: 1px solid var(--line-soft);
}

.ranking-column .rank-no {
  grid-area: no;
  font-family: var(--sans);
  font-size: 15px;
  font-weight: 600;
  color: var(--accent);
}

.ranking-column .rank-work {
  grid-area: work;
  font-size: 16px;
  color: var(--ink);
}

.ranking-column .rank-topic {
  grid-area: topic;
  font-family: var(--sans);
  font-size: 12px;
  color: var(--ink-soft);
  text-align: right;
}

.ranking-column .rank-note {
  grid-area: note;
  font-size: 13px;
  color: var(--ink-soft);
  margin: 0;
}

/* 字段口径摘要 */
.fields-column {
  min-width: 0;
  padding: 22px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.field-glossary {
  margin-bottom: 16px;
}

.field-glossary .field-name {
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--accent);
  margin-top: 12px;
}

.field-glossary .field-name:first-of-type {
  margin-top: 0;
}

.field-glossary .field-desc {
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
  margin-top: 4px;
}

.fields-note {
  padding-top: 14px;
  border-top: 1px dashed var(--line);
  font-size: 14px;
  color: var(--ink-soft);
}

/* 站内栏目索引 */
.site-index {
  padding-top: 44px;
  padding-bottom: 8px;
  border-top: 1px solid var(--line);
}

.index-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 18px;
}

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

.index-name {
  font-family: var(--serif);
  font-size: 17px;
  margin-bottom: 8px;
}

.index-name a {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
}

.index-desc {
  font-size: 13px;
  line-height: 1.7;
  color: var(--ink-soft);
  margin: 0;
}

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

.topic-table-section,
.choice-guide {
  padding-bottom: 44px;
}

.topic-table-section {
  padding-top: 4px;
}

.table-scroll {
  margin-top: 22px;
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
}

.topic-table {
  width: 100%;
  min-width: 660px;
  border-collapse: collapse;
  font-size: 15px;
}

.topic-table-caption {
  caption-side: top;
  padding: 14px 18px;
  text-align: left;
  font-family: var(--sans);
  font-size: 13px;
  color: var(--ink-soft);
  border-bottom: 1px solid var(--line);
}

.topic-table thead th {
  padding: 12px 18px;
  text-align: left;
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.05em;
  color: var(--accent);
  background: #f4f2ee;
  border-bottom: 1px solid var(--line);
  white-space: nowrap;
}

.topic-table tbody th {
  padding: 14px 18px;
  text-align: left;
  font-family: var(--serif);
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
  border-bottom: 1px solid var(--line-soft);
  white-space: nowrap;
}

.topic-table tbody td {
  padding: 14px 18px;
  color: var(--ink-soft);
  border-bottom: 1px solid var(--line-soft);
  vertical-align: top;
}

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

.topic-figure {
  margin: 26px 0 0;
}

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

.choice-guide {
  padding-top: 40px;
  border-top: 1px solid var(--line);
}

.guide-steps {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  margin-top: 22px;
  counter-reset: guide-step;
}

.guide-step {
  padding: 22px 20px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.guide-step .step-title {
  font-family: var(--serif);
  font-size: 18px;
  margin-bottom: 8px;
}

.guide-step .step-title::before {
  counter-increment: guide-step;
  content: counter(guide-step, decimal-leading-zero);
  display: block;
  font-family: var(--sans);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--accent-soft);
  margin-bottom: 6px;
}

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

.guide-tail {
  margin-top: 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ============ page: updates ============ */

.date-track {
  padding-top: 4px;
  padding-bottom: 40px;
}

.track-day {
  display: grid;
  grid-template-columns: 168px minmax(0, 1fr);
  gap: 24px;
  padding: 24px 0;
  border-top: 1px solid var(--line);
}

.track-day:first-of-type {
  border-top: 0;
  padding-top: 8px;
}

.day-head {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding-top: 2px;
}

.day-date {
  font-family: var(--sans);
  font-size: 15px;
  font-weight: 600;
  color: var(--accent);
}

.day-count {
  font-family: var(--sans);
  font-size: 12px;
  color: var(--ink-soft);
}

.day-entries {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  min-width: 0;
}

.update-card {
  display: grid;
  grid-template-columns: 76px minmax(0, 1fr);
  gap: 14px;
  padding: 14px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: border-color 0.18s ease;
}

.update-card:hover {
  border-color: var(--accent-soft);
}

.update-thumb {
  margin: 0;
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--line-soft);
}

.update-thumb img {
  width: 100%;
  aspect-ratio: 3 / 4;
  object-fit: cover;
}

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

.update-name {
  font-family: var(--serif);
  font-size: 16px;
  line-height: 1.4;
  margin-bottom: 8px;
}

.update-fields {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 4px 10px;
  font-size: 13px;
}

.update-fields .field-name {
  font-family: var(--sans);
  font-size: 12px;
  color: var(--ink-soft);
  white-space: nowrap;
}

.update-fields .field-desc {
  color: var(--ink);
  min-width: 0;
  overflow-wrap: anywhere;
}

.field-note {
  padding-top: 40px;
  border-top: 1px solid var(--line);
}

.field-list {
  margin-top: 22px;
  border-top: 1px solid var(--line);
}

.field-list .field-row {
  display: grid;
  grid-template-columns: 168px minmax(0, 1fr);
  gap: 20px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line-soft);
}

.field-list .field-name {
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--accent);
}

.field-list .field-desc {
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

/* ============ page: ranking ============ */

.rank-section {
  padding-top: 4px;
  padding-bottom: 44px;
}

.rank-section .rank-list {
  margin-top: 22px;
  border-top: 1px solid var(--line);
}

.rank-section .rank-item {
  display: grid;
  grid-template-columns: 76px 44px minmax(0, 1fr);
  grid-template-areas:
    "cover pos body"
    "cover pos body";
  gap: 16px;
  align-items: start;
  padding: 18px 0;
  border-bottom: 1px solid var(--line-soft);
}

.rank-section .rank-cover {
  grid-area: cover;
  margin: 0;
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--line-soft);
}

.rank-section .rank-cover img {
  width: 100%;
  aspect-ratio: 3 / 4;
  object-fit: cover;
}

.rank-section .rank-body {
  grid-area: body;
  min-width: 0;
}

.rank-section .rank-position {
  grid-area: pos;
  font-family: var(--sans);
  font-size: 20px;
  font-weight: 600;
  color: var(--accent);
  line-height: 1.2;
  margin: 0;
}

.rank-section .rank-name {
  font-family: var(--serif);
  font-size: 19px;
  margin-bottom: 4px;
}

.rank-section .rank-topic {
  font-family: var(--sans);
  font-size: 12px;
  color: var(--accent-soft);
  margin-bottom: 6px;
}

.rank-section .rank-note {
  font-size: 14px;
  color: var(--ink-soft);
  margin: 0;
}

.rank-footnote {
  margin-top: 22px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.rank-note-section {
  padding-top: 40px;
  border-top: 1px solid var(--line);
}

.rank-note-section .section-desc a {
  margin-left: 4px;
}

.note-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  margin-top: 22px;
}

.note-card {
  padding: 20px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.note-card .note-title {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-family: var(--serif);
  font-size: 17px;
  margin-bottom: 8px;
}

.note-card .note-index {
  font-family: var(--sans);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--accent-soft);
}

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

.rank-media {
  margin: 28px 0 0;
}

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

.rank-back {
  margin-top: 26px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

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

.guide-section {
  padding-bottom: 44px;
}

.guide-section + .guide-section {
  padding-top: 40px;
  border-top: 1px solid var(--line);
}

.field-boundary {
  padding-top: 4px;
}

.field-layout {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 32px;
  margin-top: 24px;
}

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

.field-col .col-title {
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-soft);
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 14px;
}

.field-col .field-list {
  margin-top: 0;
  border-top: 0;
}

.field-col .field-name {
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  margin-top: 12px;
}

.field-col .field-name:first-of-type {
  margin-top: 0;
}

.field-col .field-desc {
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
  margin-top: 4px;
}

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

.boundary-item {
  padding: 12px 14px;
  background: var(--card);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent-soft);
  border-radius: var(--radius);
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.guide-figure {
  margin: 28px 0 0;
}

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

.figure-caption {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 14px;
}

.figure-caption .fn-mark {
  font-family: var(--sans);
  font-size: 12px;
  color: var(--accent);
}

.path-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  margin-top: 24px;
}

.path-item {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 14px;
  padding: 20px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.path-num {
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 600;
  color: var(--accent-soft);
  padding-top: 2px;
}

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

.path-title {
  font-family: var(--serif);
  font-size: 17px;
  margin-bottom: 6px;
}

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

.guide-note {
  margin-top: 26px;
  padding: 20px 22px;
  background: #f4f2ee;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.guide-note .note-title {
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin-bottom: 10px;
}

.note-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.note-item {
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.note-item .fn-mark {
  font-family: var(--sans);
  font-size: 12px;
  color: var(--accent);
  margin-right: 6px;
}

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 24px;
}

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

.faq-question {
  display: flex;
  align-items: center;
  min-height: 48px;
  padding: 12px 18px;
  cursor: pointer;
  font-family: var(--serif);
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
  list-style: none;
}

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

.faq-question::after {
  content: "+";
  margin-left: auto;
  padding-left: 14px;
  font-family: var(--sans);
  font-size: 18px;
  color: var(--accent);
}

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

.faq-answer {
  margin: 0;
  padding: 0 18px 16px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink-soft);
  border-top: 1px solid var(--line-soft);
  padding-top: 14px;
}

.guide-index {
  padding-bottom: 0;
}

.index-list {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

.index-item a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
  font-family: var(--sans);
  font-size: 14px;
  color: var(--accent);
}

.index-item a:hover,
.index-item a:focus-visible {
  border-color: var(--accent-soft);
  text-decoration: none;
}

/* ============ page: 404 ============ */

.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  padding-top: 64px;
  padding-bottom: 64px;
}

.error-panel {
  width: 100%;
  max-width: 640px;
  padding: 40px 32px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  text-align: center;
}

.error-code {
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--accent);
  margin-bottom: 12px;
}

.error-panel h1 {
  font-family: var(--serif);
  font-size: 30px;
  margin-bottom: 12px;
}

.error-text {
  max-width: 480px;
  margin: 0 auto 24px;
  font-size: 16px;
  color: var(--ink-soft);
}

.error-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}

.error-links a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--bg);
  font-family: var(--sans);
  font-size: 14px;
  color: var(--accent);
}

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

/* ============ 滚动出现增强（不影响初始可见） ============ */

.reveal {
  transition: transform 0.5s ease;
}

.reveal.is-visible {
  transform: none;
}

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

@media (max-width: 1024px) {
  .hero-summary {
    grid-template-columns: minmax(0, 1fr);
    gap: 32px;
    padding-top: 40px;
    padding-bottom: 40px;
  }

  .hero-title {
    font-size: 34px;
  }

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

  .covers-and-updates,
  .ranking-and-fields {
    grid-template-columns: minmax(0, 1fr);
    gap: 32px;
  }

  .index-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

@media (max-width: 768px) {
  body {
    font-size: 16px;
  }

  .header-inner,
  .footer-inner,
  .site-main > section,
  .site-main > nav.breadcrumb,
  .site-main > div.page-header,
  .site-main > header.page-header {
    padding-left: 18px;
    padding-right: 18px;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: block;
    background: var(--bg);
    border-bottom: 1px solid var(--line);
    box-shadow: 0 8px 18px rgba(35, 38, 43, 0.08);
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px 18px 14px;
  }

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

  .nav-list a {
    min-height: 48px;
    padding: 0 4px;
    border-bottom: 1px solid var(--line-soft);
  }

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

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

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

  .hero-paths {
    flex-direction: column;
  }

  .hero-path a {
    min-width: 0;
    width: 100%;
  }

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

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

  .ranking-column .rank-item {
    grid-template-columns: 36px minmax(0, 1fr);
    grid-template-areas:
      "no work"
      "no topic"
      "note note";
  }

  .ranking-column .rank-topic {
    text-align: left;
  }

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

  .track-day {
    grid-template-columns: minmax(0, 1fr);
    gap: 12px;
  }

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

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

  .rank-section .rank-item {
    grid-template-columns: 64px 36px minmax(0, 1fr);
    gap: 12px;
  }

  .note-grid,
  .guide-steps,
  .path-list,
  .field-layout {
    grid-template-columns: minmax(0, 1fr);
  }

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

@media (max-width: 480px) {
  .cover-grid {
    grid-template-columns: minmax(0, 1fr);
  }

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

  .rank-section .rank-item {
    grid-template-columns: 56px minmax(0, 1fr);
    grid-template-areas:
      "cover body"
      "pos body";
    align-items: center;
  }

  .rank-section .rank-position {
    font-size: 16px;
  }

  .update-card {
    grid-template-columns: 64px minmax(0, 1fr);
  }

  .error-panel {
    padding: 32px 20px;
  }
}