/* ==========================================================================
   xiao-bang.com 全站样式
   分组：base / layout / components / pages / responsive
   ========================================================================== */

/* --------------------------------------------------------------------------
   base
   -------------------------------------------------------------------------- */

:root {
  --canvas: #f5f5f3;
  --surface: #ffffff;
  --ink: #1f1f1f;
  --ink-soft: #6b6b6b;
  --rule: #b8b8b4;
  --rule-soft: #e2e2de;
  --channel: #3d5a4c;
  --collection: #8a7a5c;
  --radius: 6px;
  --radius-sm: 4px;
  --wrap: 1120px;
  --header-h: 60px;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-mono: "SFMono-Regular", Menlo, Consolas, "Liberation Mono", monospace;
}

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

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

body.site-body {
  margin: 0;
  padding: 0;
  background: var(--canvas);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  font-weight: 400;
  line-height: 1.75;
  scroll-padding-top: calc(var(--header-h) + 16px);
}

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

a {
  color: var(--channel);
  text-decoration: none;
}

a:hover,
a:focus-visible {
  text-decoration: underline;
}

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

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

p {
  margin: 0;
}

ul,
ol,
dl,
dd,
figure {
  margin: 0;
  padding: 0;
}

li {
  list-style: none;
}

button {
  font: inherit;
  color: inherit;
}

code,
.channel-code,
.index-code,
.step-code,
.step-num,
.order-index,
.advice-index,
.log-date,
.collection-tag {
  font-family: var(--font-mono);
}

/* --------------------------------------------------------------------------
   layout —— 全站骨架
   -------------------------------------------------------------------------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: var(--surface);
  border-bottom: 1px solid var(--rule-soft);
}

.header-inner {
  max-width: var(--wrap);
  min-height: var(--header-h);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 17px;
  font-weight: 600;
  color: var(--ink);
  text-decoration: none;
}

.brand:hover {
  text-decoration: none;
  color: var(--channel);
}

.site-nav {
  position: relative;
}

.nav-toggle {
  display: none;
  min-height: 44px;
  padding: 0 16px;
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: var(--radius-sm);
  font-size: 14px;
  cursor: pointer;
}

.nav-toggle:hover {
  border-color: var(--channel);
  color: var(--channel);
}

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

.nav-list li {
  display: block;
}

.nav-list a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 12px;
  font-size: 15px;
  color: var(--ink-soft);
  border-radius: var(--radius-sm);
  text-decoration: none;
}

.nav-list a:hover {
  color: var(--ink);
  background: var(--canvas);
  text-decoration: none;
}

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

.site-main {
  display: block;
}

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

.home-main {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 24px 72px;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: 20px 0 0;
  font-size: 13px;
  color: var(--ink-soft);
}

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

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

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

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

.page-header {
  padding: 18px 0 30px;
  border-bottom: 1px solid var(--rule-soft);
  margin-bottom: 40px;
}

.page-title {
  font-size: 30px;
  font-weight: 600;
  color: var(--ink);
}

.page-description {
  margin-top: 14px;
  max-width: 780px;
  font-size: 16px;
  color: var(--ink-soft);
}

.page-lead {
  margin-top: 10px;
  max-width: 780px;
  font-size: 15px;
  color: var(--ink-soft);
}

/* 通用区块头部 */
.section-head {
  margin-bottom: 22px;
}

.section-head h2 {
  font-size: 22px;
}

.section-desc,
.section-note {
  margin-top: 8px;
  max-width: 760px;
  font-size: 15px;
  color: var(--ink-soft);
}

.section-intro {
  margin: 8px 0 22px;
  max-width: 760px;
  font-size: 15px;
  color: var(--ink-soft);
}

.sub-title {
  font-size: 16px;
  margin-bottom: 12px;
}

/* --------------------------------------------------------------------------
   components —— 页脚 / 按钮 / 卡片 / 列表通用件
   -------------------------------------------------------------------------- */

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

.footer-inner {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 44px 24px 0;
  display: grid;
  grid-template-columns: minmax(220px, 1.4fr) repeat(4, minmax(150px, 1fr));
  gap: 28px 24px;
}

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

.footer-brand {
  font-size: 16px;
  font-weight: 600;
  color: var(--ink);
}

.footer-desc {
  margin-top: 10px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

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

.footer-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 10px;
}

.footer-group ul {
  display: grid;
  gap: 2px;
}

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

.footer-group li a:hover {
  color: var(--channel);
}

.footer-copy {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 20px 24px 30px;
  font-size: 13px;
  color: var(--ink-soft);
  border-top: 1px solid var(--rule-soft);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 22px;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  border: 1px solid transparent;
}

.btn:hover {
  text-decoration: none;
}

.btn-primary {
  background: var(--channel);
  color: #ffffff;
}

.btn-primary:hover {
  background: #32493e;
  color: #ffffff;
}

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

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

/* 频道目录行（首页概览） */
.channel-rows {
  border-top: 1px solid var(--rule-soft);
}

.channel-row {
  display: grid;
  grid-template-columns: 92px minmax(120px, 1fr) minmax(180px, 1.4fr) minmax(180px, 1.4fr);
  gap: 16px;
  align-items: baseline;
  padding: 16px 12px;
  border-bottom: 1px solid var(--rule-soft);
  transition: background-color 0.18s ease;
}

.channel-row:hover {
  background: #efefec;
}

.channel-code {
  font-size: 13px;
  color: var(--ink-soft);
  letter-spacing: 0.02em;
}

.channel-topic {
  font-size: 16px;
  font-weight: 600;
  color: var(--channel);
}

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

/* 片单卡 */
.collection-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
}

.collection-card {
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 1px solid var(--rule-soft);
  border-radius: var(--radius);
  overflow: hidden;
}

.collection-cover {
  margin: 0;
  aspect-ratio: 16 / 9;
  background: #e8e8e4;
}

.collection-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

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

.collection-theme {
  margin-top: 8px;
  font-size: 14px;
  color: var(--ink-soft);
}

/* 四步顺序条 */
.step-list {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.step-item {
  background: var(--surface);
  border: 1px solid var(--rule-soft);
  border-radius: var(--radius);
  padding: 20px 18px;
  min-width: 0;
}

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

.step-name {
  font-size: 16px;
  margin-bottom: 8px;
}

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

/* 字段口径简表 */
.field-list {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--rule-soft);
}

.field-item {
  display: grid;
  grid-template-columns: minmax(96px, 130px) minmax(0, 1fr);
  gap: 14px;
  padding: 12px 0;
  border-bottom: 1px solid var(--rule-soft);
}

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

.field-item dd {
  font-size: 14px;
  color: var(--ink-soft);
}

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

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

.boundary-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 5px;
  height: 5px;
  background: var(--collection);
  border-radius: 50%;
}

/* 站内栏目索引 */
.index-columns {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 18px;
  border-top: 1px solid var(--rule-soft);
  padding-top: 22px;
}

.index-col {
  min-width: 0;
  padding-right: 12px;
}

.index-code {
  display: block;
  font-size: 13px;
  color: var(--ink-soft);
  margin-bottom: 8px;
}

.index-col a {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  font-size: 16px;
  font-weight: 600;
  color: var(--channel);
}

.index-col p {
  margin-top: 6px;
  font-size: 13px;
  color: var(--ink-soft);
}

/* 整理记录条目 */
.log-list {
  border-top: 1px solid var(--rule-soft);
}

.log-item {
  display: grid;
  grid-template-columns: 110px 160px minmax(0, 1fr);
  gap: 16px;
  padding: 14px 0;
  border-bottom: 1px solid var(--rule-soft);
}

.log-date {
  font-size: 13px;
  color: var(--ink-soft);
}

.log-scope {
  font-size: 14px;
  font-weight: 600;
  color: var(--ink);
}

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

/* 字段三列表格 */
.field-table-grid {
  width: 100%;
  border-collapse: collapse;
  background: var(--surface);
  border: 1px solid var(--rule-soft);
  border-radius: var(--radius);
  overflow: hidden;
}

.field-table-grid caption {
  caption-side: top;
  text-align: left;
  padding: 0 0 12px;
  font-size: 13px;
  color: var(--ink-soft);
}

.field-table-grid th,
.field-table-grid td {
  padding: 13px 16px;
  font-size: 14px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--rule-soft);
}

.field-table-grid thead th {
  background: #eeeeea;
  font-weight: 600;
  color: var(--ink);
}

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

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

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

/* FAQ 折叠 */
.faq-item {
  background: var(--surface);
  border: 1px solid var(--rule-soft);
  border-radius: var(--radius);
  padding: 0 18px;
  margin-bottom: 10px;
}

.faq-item summary {
  cursor: pointer;
  padding: 14px 0;
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
  list-style: none;
}

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

.faq-item summary::after {
  content: "＋";
  float: right;
  color: var(--ink-soft);
  font-weight: 400;
}

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

.faq-item p {
  padding: 0 0 16px;
  font-size: 14px;
  color: var(--ink-soft);
}

/* 404 */
.error-main {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 72px 24px 96px;
}

.error-block {
  max-width: 620px;
}

.error-code {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ink-soft);
  margin-bottom: 10px;
}

.error-block h1 {
  font-size: 30px;
  margin-bottom: 14px;
}

.error-text {
  font-size: 16px;
  color: var(--ink-soft);
}

.error-links {
  margin-top: 26px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.error-links li a {
  display: flex;
  align-items: center;
  min-height: 44px;
  padding: 0 16px;
  background: var(--surface);
  border: 1px solid var(--rule-soft);
  border-radius: var(--radius-sm);
  font-size: 15px;
  color: var(--ink);
}

.error-links li a:hover {
  border-color: var(--channel);
  color: var(--channel);
  text-decoration: none;
}

/* --------------------------------------------------------------------------
   pages —— 首页
   -------------------------------------------------------------------------- */

.home-main section {
  margin-bottom: 56px;
}

.home-main section:last-child {
  margin-bottom: 0;
}

.hero {
  padding-top: 40px;
}

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
  gap: 40px;
  align-items: start;
}

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

.hero-eyebrow {
  font-size: 13px;
  font-family: var(--font-mono);
  color: var(--collection);
  margin-bottom: 12px;
}

.hero-title {
  font-size: 30px;
  line-height: 1.35;
}

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

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

.hero-media {
  margin: 0;
  background: var(--surface);
  border: 1px solid var(--rule-soft);
  border-radius: var(--radius);
  overflow: hidden;
}

.hero-media img {
  width: 100%;
  aspect-ratio: 16 / 10;
  height: auto;
  object-fit: cover;
}

.hero-media figcaption {
  padding: 12px 16px;
  font-size: 13px;
  color: var(--ink-soft);
  border-top: 1px solid var(--rule-soft);
}

.hero-stats {
  margin-top: 36px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  border-top: 1px solid var(--rule-soft);
  border-bottom: 1px solid var(--rule-soft);
}

.stat {
  padding: 18px 16px;
  border-right: 1px solid var(--rule-soft);
  min-width: 0;
}

.stat:last-child {
  border-right: 0;
}

.stat dt {
  font-size: 13px;
  color: var(--ink-soft);
  font-family: var(--font-mono);
}

.stat dd {
  margin: 6px 0 0;
  font-size: 16px;
  font-weight: 600;
  color: var(--ink);
}

.collection-entry .collection-card {
  padding: 0;
}

.collection-entry .collection-name {
  padding: 16px 18px 0;
}

.collection-entry .collection-theme {
  padding: 0 18px 18px;
}

.glossary-columns {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
  gap: 40px;
  align-items: start;
}

.glossary-fields,
.glossary-boundary {
  min-width: 0;
}

.glossary-boundary > p {
  font-size: 14px;
  color: var(--ink-soft);
  margin-bottom: 14px;
}

/* --------------------------------------------------------------------------
   pages —— 频道分类
   -------------------------------------------------------------------------- */

.channel-list .channel-row {
  display: grid;
  grid-template-columns: 200px minmax(0, 1fr) minmax(200px, 0.85fr);
  gap: 24px;
  align-items: start;
  padding: 22px 0;
  border-bottom: 1px solid var(--rule-soft);
  background: transparent;
  transition: background-color 0.18s ease;
}

.channel-list .channel-row:hover {
  background: #efefec;
}

.channel-list .channel-row:first-child {
  border-top: 1px solid var(--rule-soft);
}

.channel-thumb {
  margin: 0;
  aspect-ratio: 16 / 9;
  background: #e8e8e4;
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.channel-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

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

.channel-main .channel-code {
  font-size: 13px;
  color: var(--ink-soft);
  margin-bottom: 6px;
}

.channel-name {
  font-size: 18px;
  color: var(--channel);
  margin-bottom: 10px;
}

.channel-field {
  font-size: 14px;
  color: var(--ink-soft);
  margin-bottom: 4px;
}

.field-label {
  display: inline-block;
  min-width: 84px;
  font-size: 13px;
  color: var(--ink);
  font-weight: 600;
}

.channel-list .channel-boundary {
  font-size: 14px;
  color: var(--ink-soft);
  border-left: 2px solid var(--rule-soft);
  padding-left: 16px;
}

.boundary-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.boundary-item {
  background: var(--surface);
  border: 1px solid var(--rule-soft);
  border-radius: var(--radius);
  padding: 18px;
  min-width: 0;
}

.boundary-item h3 {
  font-size: 15px;
  margin-bottom: 8px;
}

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

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

.advice-foot a {
  margin-right: 16px;
}

.advice-steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.advice-step {
  background: var(--surface);
  border: 1px solid var(--rule-soft);
  border-radius: var(--radius);
  padding: 18px;
  min-width: 0;
}

.advice-index {
  font-size: 13px;
  color: var(--collection);
  margin-bottom: 8px;
}

.advice-step h3 {
  font-size: 16px;
  margin-bottom: 8px;
}

.advice-step p {
  font-size: 14px;
  color: var(--ink-soft);
}

/* --------------------------------------------------------------------------
   pages —— 专题片单
   -------------------------------------------------------------------------- */

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

.collection-tag {
  font-size: 13px;
  color: var(--collection);
  margin-bottom: 6px;
}

.collection-meta {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid var(--rule-soft);
  display: grid;
  grid-template-columns: 84px minmax(0, 1fr);
  gap: 4px 12px;
}

.collection-meta dt {
  font-size: 13px;
  color: var(--ink);
  font-weight: 600;
}

.collection-meta dd {
  font-size: 13px;
  color: var(--ink-soft);
}

.order-list {
  border-top: 1px solid var(--rule-soft);
}

.order-item {
  display: grid;
  grid-template-columns: 90px minmax(140px, 220px) minmax(0, 1fr);
  gap: 20px;
  align-items: baseline;
  padding: 16px 0;
  border-bottom: 1px solid var(--rule-soft);
}

.order-index {
  font-size: 13px;
  color: var(--ink-soft);
}

.order-name {
  font-size: 16px;
  color: var(--ink);
}

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

.map-columns {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 32px;
}

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

.map-col-title {
  font-size: 15px;
  padding-bottom: 10px;
  margin-bottom: 12px;
  border-bottom: 1px solid var(--rule-soft);
}

.map-col-collection .map-col-title {
  color: var(--collection);
}

.map-col-channel .map-col-title {
  color: var(--channel);
}

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

.map-list li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 10px;
  font-size: 14px;
}

.map-list li a {
  min-height: 32px;
  display: inline-flex;
  align-items: center;
  font-weight: 600;
}

.map-note {
  font-size: 13px;
  color: var(--ink-soft);
}

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

.map-foot a {
  margin-right: 16px;
}

/* --------------------------------------------------------------------------
   pages —— 浏览指引
   -------------------------------------------------------------------------- */

.guide-steps .step-list {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  border-top: 1px solid var(--rule-soft);
}

.guide-steps .step-item {
  display: grid;
  grid-template-columns: 76px minmax(0, 1fr) minmax(0, 320px);
  gap: 24px;
  align-items: start;
  padding: 24px 0;
  background: transparent;
  border: 0;
  border-bottom: 1px solid var(--rule-soft);
  border-radius: 0;
}

.guide-steps .step-num {
  font-size: 13px;
  color: var(--ink-soft);
  padding-top: 3px;
}

.guide-steps .step-name {
  font-size: 18px;
  color: var(--channel);
  margin-bottom: 8px;
}

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

.guide-steps .step-media {
  margin: 0;
  background: var(--surface);
  border: 1px solid var(--rule-soft);
  border-radius: var(--radius);
  overflow: hidden;
}

.guide-steps .step-media img {
  width: 100%;
  aspect-ratio: 16 / 10;
  height: auto;
  object-fit: cover;
}

.guide-steps .step-media figcaption {
  padding: 10px 12px;
  font-size: 13px;
  color: var(--ink-soft);
  border-top: 1px solid var(--rule-soft);
}

.guide-steps .step-link {
  grid-column: 2 / 3;
  margin-top: 10px;
  font-size: 14px;
}

.confirm-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.confirm-item {
  background: var(--surface);
  border: 1px solid var(--rule-soft);
  border-radius: var(--radius);
  padding: 18px;
  min-width: 0;
}

.confirm-item h3 {
  font-size: 15px;
  margin-bottom: 8px;
}

.confirm-item p {
  font-size: 14px;
  color: var(--ink-soft);
}

.notes-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.note-card {
  background: var(--surface);
  border: 1px solid var(--rule-soft);
  border-radius: var(--radius);
  padding: 18px;
  min-width: 0;
}

.note-card h3 {
  font-size: 15px;
  margin-bottom: 8px;
}

.note-card p {
  font-size: 14px;
  color: var(--ink-soft);
}

/* --------------------------------------------------------------------------
   pages —— 字段说明
   -------------------------------------------------------------------------- */

.glossary-visual {
  margin-bottom: 44px;
}

.glossary-visual h2 {
  font-size: 22px;
  margin-bottom: 16px;
}

.glossary-figure {
  margin: 0;
  background: var(--surface);
  border: 1px solid var(--rule-soft);
  border-radius: var(--radius);
  overflow: hidden;
}

.glossary-figure img {
  width: 100%;
  aspect-ratio: 21 / 9;
  height: auto;
  object-fit: cover;
}

.glossary-figure figcaption {
  padding: 12px 16px;
  font-size: 13px;
  color: var(--ink-soft);
  border-top: 1px solid var(--rule-soft);
}

.field-table {
  margin-bottom: 48px;
}

.field-table h2,
.boundary-rule h2,
.misconception h2,
.glossary-links h2 {
  font-size: 22px;
}

.boundary-rule {
  margin-bottom: 48px;
}

.boundary-rule .boundary-list {
  gap: 0;
  border-top: 1px solid var(--rule-soft);
}

.boundary-rule .boundary-list li {
  padding: 16px 0;
  border-bottom: 1px solid var(--rule-soft);
}

.boundary-rule .boundary-list li::before {
  display: none;
}

.boundary-rule .boundary-list h3 {
  font-size: 16px;
  margin-bottom: 6px;
}

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

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

.boundary-note a {
  margin-right: 16px;
}

.misconception {
  margin-bottom: 48px;
}

.glossary-links {
  padding-top: 24px;
  border-top: 1px solid var(--rule-soft);
}

.glossary-links p {
  margin-top: 12px;
  font-size: 15px;
  color: var(--ink-soft);
}

.glossary-links p a {
  margin-right: 18px;
}

/* --------------------------------------------------------------------------
   responsive
   -------------------------------------------------------------------------- */

@media (max-width: 1024px) {
  .footer-inner {
    grid-template-columns: minmax(0, 1.4fr) repeat(2, minmax(0, 1fr));
  }

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

  .index-col:nth-child(3) {
    padding-right: 0;
  }

  .channel-list .channel-row {
    grid-template-columns: 180px minmax(0, 1fr);
  }

  .channel-list .channel-boundary {
    grid-column: 1 / -1;
    border-left: 0;
    border-top: 1px solid var(--rule-soft);
    padding: 12px 0 0;
  }

  .guide-steps .step-item {
    grid-template-columns: 68px minmax(0, 1fr);
  }

  .guide-steps .step-media {
    grid-column: 2 / 3;
    margin-top: 14px;
  }

  .guide-steps .step-link {
    grid-column: 2 / 3;
  }

  .boundary-grid,
  .advice-steps,
  .notes-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 768px) {
  :root {
    --header-h: 56px;
  }

  .header-inner {
    padding: 0 16px;
  }

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

  .nav-list {
    display: none;
    position: absolute;
    right: 0;
    top: calc(100% + 8px);
    width: min(280px, calc(100vw - 32px));
    padding: 8px;
    background: var(--surface);
    border: 1px solid var(--rule-soft);
    border-radius: var(--radius);
    box-shadow: 0 10px 24px rgba(31, 31, 31, 0.1);
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
  }

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

  .nav-list a {
    display: flex;
    width: 100%;
    min-height: 48px;
    padding: 0 14px;
  }

  .home-main,
  .inner-main {
    padding: 0 16px 56px;
  }

  .hero {
    padding-top: 28px;
  }

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

  .hero-title,
  .page-title,
  .error-block h1 {
    font-size: 24px;
  }

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

  .section-head h2,
  .glossary-visual h2,
  .field-table h2,
  .boundary-rule h2,
  .misconception h2,
  .glossary-links h2 {
    font-size: 19px;
  }

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

  .stat {
    border-right: 0;
    border-bottom: 1px solid var(--rule-soft);
  }

  .stat:last-child {
    border-bottom: 0;
  }

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

  .channel-list .channel-row {
    grid-template-columns: minmax(0, 1fr);
    gap: 12px;
  }

  .channel-list .channel-boundary {
    border-top: 1px solid var(--rule-soft);
    padding-top: 12px;
  }

  .collection-grid,
  .glossary-columns,
  .map-columns,
  .confirm-list,
  .boundary-grid,
  .advice-steps,
  .notes-grid,
  .error-links {
    grid-template-columns: minmax(0, 1fr);
  }

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

  .guide-steps .step-item {
    grid-template-columns: minmax(0, 1fr);
    gap: 10px;
    padding: 20px 0;
  }

  .guide-steps .step-media,
  .guide-steps .step-link {
    grid-column: 1 / -1;
    margin-top: 0;
  }

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

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

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

  .index-col {
    padding-right: 0;
  }

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

  .field-table-grid th,
  .field-table-grid td {
    padding: 11px 12px;
  }

  .field-table-grid tbody th {
    white-space: normal;
  }

  .footer-inner {
    grid-template-columns: minmax(0, 1fr);
    padding: 36px 16px 0;
    gap: 24px;
  }

  .footer-copy {
    padding: 18px 16px 26px;
  }

  .error-main {
    padding: 48px 16px 72px;
  }
}

@media (max-width: 480px) {
  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .btn {
    width: 100%;
  }

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

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

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

  .collection-meta dt {
    margin-top: 8px;
  }

  .field-label {
    display: block;
    min-width: 0;
    margin-bottom: 2px;
  }
}

/* 进入视口的轻量淡入，仅作增强，不影响初始可见性 */
.fade-in {
  animation: fade-in-up 0.42s ease both;
}

@keyframes fade-in-up {
  from {
    transform: translateY(10px);
  }
  to {
    transform: translateY(0);
  }
}

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

  .fade-in {
    animation: none;
  }
}