:root {
  --bg: #f7f7f5;
  --surface: #ffffff;
  --ink: #1f2328;
  --ink-soft: #5b6169;
  --line: #e3e4e6;
  --accent: #1f6f5c;
  --accent-dark: #175647;
  --radius: 6px;
  --radius-sm: 4px;
  --shadow: 0 1px 2px rgba(31, 35, 40, 0.04);
  --wrap: 1120px;
  --read: 720px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

/* ============================================================
   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(--font);
  font-size: 16px;
  line-height: 1.75;
  font-weight: 400;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3 {
  margin: 0;
  color: var(--ink);
  font-weight: 600;
  line-height: 1.35;
}

p {
  margin: 0;
}

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

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

a:hover,
a:focus-visible {
  color: var(--accent-dark);
  text-decoration: underline;
}

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

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

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

/* ============================================================
   layout — 全站骨架
   ============================================================ */

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

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 14px 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  text-decoration: none;
}

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

.brand-mark {
  display: inline-block;
  width: 10px;
  height: 22px;
  background: var(--accent);
  border-radius: 2px;
}

.brand-slogan {
  font-size: 17px;
  font-weight: 600;
  line-height: 1.3;
}

.site-nav {
  display: block;
}

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

.nav-link {
  display: inline-block;
  padding: 8px 14px;
  min-height: 44px;
  line-height: 28px;
  color: var(--ink);
  font-size: 15px;
  border-bottom: 2px solid transparent;
  text-decoration: none;
}

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

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

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

.nav-toggle-bar {
  display: block;
  width: 20px;
  height: 2px;
  margin: 0 auto;
  background: var(--ink);
}

.site-main {
  display: block;
}

.inner-main {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 24px 24px 72px;
}

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 4px 0 18px;
  font-size: 14px;
  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-bottom: 22px;
  margin-bottom: 32px;
  border-bottom: 1px solid var(--line);
}

.page-title {
  font-size: 32px;
  font-weight: 600;
  line-height: 1.35;
}

.page-description {
  max-width: var(--read);
  margin-top: 12px;
  color: var(--ink-soft);
  font-size: 16px;
}

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

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 40px;
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 44px 24px 32px;
}

.footer-about {
  flex: 1 1 240px;
  max-width: 300px;
}

.footer-brand {
  color: var(--ink);
  font-size: 17px;
  font-weight: 600;
}

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

.footer-nav {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 28px;
  flex: 2 1 520px;
}

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

.footer-list li + li {
  margin-top: 6px;
}

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

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

.footer-bottom {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 18px 24px 28px;
  border-top: 1px solid var(--line);
}

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

/* ============================================================
   components — 通用
   ============================================================ */

.btn {
  display: inline-block;
  padding: 11px 22px;
  min-height: 44px;
  line-height: 22px;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  text-align: center;
  text-decoration: none;
  transition: background-color 0.18s ease, color 0.18s ease, border-color 0.18s ease;
}

.btn-primary {
  display: inline-block;
  padding: 11px 22px;
  min-height: 44px;
  line-height: 22px;
  background: var(--accent);
  color: #ffffff;
  border: 1px solid var(--accent);
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  text-align: center;
  text-decoration: none;
  transition: background-color 0.18s ease, border-color 0.18s ease;
}

.btn-primary:hover,
.btn-primary:focus-visible {
  background: var(--accent-dark);
  border-color: var(--accent-dark);
  color: #ffffff;
  text-decoration: none;
}

.btn-ghost {
  background: transparent;
  color: var(--accent);
  border: 1px solid var(--line);
}

.btn-ghost:hover,
.btn-ghost:focus-visible {
  border-color: var(--accent);
  color: var(--accent-dark);
  text-decoration: none;
}

.link-arrow {
  display: inline-block;
  padding: 4px 0;
  min-height: 32px;
  color: var(--accent);
  font-size: 15px;
  font-weight: 600;
}

.link-arrow::after {
  content: "→";
  margin-left: 6px;
  font-weight: 400;
}

.link-arrow:hover,
.link-arrow:focus-visible {
  color: var(--accent-dark);
}

.section-title {
  font-size: 22px;
  font-weight: 600;
}

.section-intro,
.section-lead,
.section-note {
  margin-top: 12px;
  color: var(--ink-soft);
  font-size: 15px;
  line-height: 1.75;
}

.section-note a {
  font-weight: 600;
}

.media-figure,
.content-figure,
.guide-figure {
  margin: 24px 0 0;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.media-figure img,
.content-figure img,
.guide-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background: var(--bg);
}

.media-figure figcaption,
.content-figure figcaption,
.guide-figure-caption {
  padding: 12px 16px;
  color: var(--ink-soft);
  font-size: 14px;
  border-top: 1px solid var(--line);
}

.table-scroll {
  margin-top: 20px;
  overflow-x: auto;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

/* ============================================================
   pages — 首页
   ============================================================ */

.home-main {
  display: block;
}

.hero-section {
  background: var(--surface);
  border-bottom: 1px solid var(--line);
}

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  align-items: start;
  gap: 48px;
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 56px 24px 60px;
}

.hero-select {
  max-width: 560px;
}

.hero-title {
  font-size: 32px;
  font-weight: 600;
  line-height: 1.35;
}

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

.hero-choices {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
  margin-top: 30px;
}

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

.choice-title {
  padding-bottom: 8px;
  margin-bottom: 10px;
  color: var(--ink);
  font-size: 15px;
  font-weight: 600;
  border-bottom: 1px solid var(--line);
}

.choice-list li + li {
  margin-top: 4px;
}

.choice-item {
  display: block;
  padding: 7px 10px;
  min-height: 38px;
  color: var(--ink);
  font-size: 14px;
  line-height: 24px;
  border-radius: var(--radius-sm);
  transition: background-color 0.18s ease, color 0.18s ease;
}

.choice-item:hover,
.choice-item:focus-visible {
  background: var(--bg);
  color: var(--accent);
  text-decoration: none;
}

.hero-cta-line {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

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

.hero-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  background: var(--bg);
}

.hero-figure figcaption {
  padding: 12px 16px;
  color: var(--ink-soft);
  font-size: 14px;
  border-top: 1px solid var(--line);
}

.section {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 56px 24px 0;
}

.section-head {
  max-width: var(--read);
  margin-bottom: 28px;
}

.section-desc {
  margin-top: 10px;
  color: var(--ink-soft);
  font-size: 15px;
}

.section-desc a {
  font-weight: 600;
}

.section-figure {
  margin: 28px 0 0;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.section-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 21 / 9;
  object-fit: cover;
  background: var(--bg);
}

.section-figure figcaption {
  padding: 12px 16px;
  color: var(--ink-soft);
  font-size: 14px;
  border-top: 1px solid var(--line);
}

.column-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 16px;
}

.column-card {
  padding: 20px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.column-name {
  font-size: 17px;
  font-weight: 600;
}

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

.column-count {
  margin-top: 12px;
  padding-top: 12px;
  color: var(--ink);
  font-size: 13px;
  border-top: 1px solid var(--line);
}

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

.path-card {
  padding: 22px 20px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.path-name {
  font-size: 17px;
  font-weight: 600;
}

.path-for {
  margin-top: 10px;
  color: var(--ink-soft);
  font-size: 14px;
}

.path-how {
  margin-top: 12px;
  font-size: 14px;
  line-height: 1.7;
}

.pick-main {
  padding: 26px 24px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.pick-main .pick-name {
  font-size: 19px;
  font-weight: 600;
}

.pick-main .pick-desc {
  max-width: var(--read);
  margin-top: 10px;
  color: var(--ink-soft);
  font-size: 15px;
}

.pick-main .pick-enter {
  margin-top: 18px;
}

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

.pick-sub {
  padding: 22px 20px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.pick-sub .pick-name {
  font-size: 17px;
  font-weight: 600;
}

.pick-sub .pick-desc {
  margin-top: 10px;
  color: var(--ink-soft);
  font-size: 14px;
}

.pick-sub .pick-enter {
  margin-top: 12px;
}

.changes-layout {
  display: grid;
  grid-template-columns: 200px minmax(0, 1fr);
  gap: 36px;
  align-items: start;
}

.changes-index {
  position: sticky;
  top: 88px;
  padding: 20px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.changes-index-title {
  margin-bottom: 12px;
  font-size: 15px;
  font-weight: 600;
}

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

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

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

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

.change-item {
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
}

.change-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  color: var(--ink-soft);
}

.change-tag {
  display: inline-block;
  padding: 2px 9px;
  color: var(--accent);
  background: rgba(31, 111, 92, 0.08);
  border-radius: 2px;
  font-size: 12px;
  font-weight: 600;
}

.change-text {
  margin-top: 8px;
  font-size: 15px;
  line-height: 1.75;
}

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

.topic-card {
  padding: 22px 20px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.topic-name {
  font-size: 17px;
  font-weight: 600;
}

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

.topic-enter {
  margin-top: 12px;
}

.section-limits {
  padding-bottom: 72px;
}

.limits-body {
  max-width: var(--read);
  padding: 24px 22px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

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

.limits-text + .limits-text {
  margin-top: 12px;
}

.limits-list {
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
}

.limits-list li {
  position: relative;
  padding-left: 18px;
  color: var(--ink);
  font-size: 14px;
  line-height: 1.75;
}

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

.limits-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
}

/* ============================================================
   pages — 内页通用布局
   ============================================================ */

.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 44px;
  align-items: start;
}

.layout-with-aside {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 44px;
  align-items: start;
}

.layout-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 44px;
  align-items: start;
}

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

.content-block + .content-block,
.guide-section + .guide-section {
  margin-top: 48px;
}

.content-block,
.guide-section,
.faq-group {
  min-width: 0;
}

/* 内页 — 栏目架构 */

.section-structure,
.section-scope,
.section-order,
.section-fields,
.section-next {
  margin-top: 44px;
}

.section-structure:first-child,
.section-scope:first-child {
  margin-top: 0;
}

.scope-item {
  padding: 20px 0;
  border-top: 1px solid var(--line);
}

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

.scope-name {
  font-size: 17px;
  font-weight: 600;
}

.scope-desc {
  margin-top: 8px;
  color: var(--ink);
  font-size: 15px;
  line-height: 1.75;
}

.scope-org {
  margin-top: 8px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

.order-list {
  counter-reset: order;
  margin-top: 20px;
  border-top: 1px solid var(--line);
}

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

.order-index {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  color: var(--accent);
  background: rgba(31, 111, 92, 0.08);
  border-radius: 50%;
  font-size: 13px;
  font-weight: 600;
  line-height: 1;
}

.order-text {
  min-width: 0;
  font-size: 15px;
  line-height: 1.75;
}

.field-table,
.spec-table {
  width: 100%;
  min-width: 560px;
  border-collapse: collapse;
  font-size: 14px;
}

.field-table caption,
.spec-table caption,
.table-caption {
  padding: 14px 16px;
  color: var(--ink-soft);
  font-size: 13px;
  text-align: left;
  border-bottom: 1px solid var(--line);
}

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

.field-table thead th,
.spec-table thead th {
  color: var(--ink);
  background: var(--bg);
  font-weight: 600;
  white-space: nowrap;
}

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

.next-list {
  margin-top: 20px;
}

.next-item {
  padding: 14px 0;
  border-top: 1px solid var(--line);
}

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

.next-item a {
  font-size: 15px;
  font-weight: 600;
}

.content-aside,
.sidebar,
.layout-side,
.layout-aside {
  min-width: 0;
  padding: 22px 20px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.aside-title,
.sidebar-title,
.side-title {
  font-size: 16px;
  font-weight: 600;
}

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

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

.aside-item {
  padding: 10px 0;
  border-top: 1px solid var(--line);
}

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

.aside-item a {
  display: block;
  min-height: 24px;
  font-size: 14px;
  font-weight: 600;
}

.aside-note {
  display: block;
  margin-top: 4px;
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.6;
}

/* 内页 — 工具入口 */

.entry-figure {
  margin-top: 20px;
}

.entry-list {
  margin-top: 24px;
  border-top: 1px solid var(--line);
}

.entry-item {
  padding: 20px 0;
  border-bottom: 1px solid var(--line);
}

.entry-name {
  font-size: 17px;
  font-weight: 600;
}

.entry-purpose {
  margin-top: 8px;
  font-size: 15px;
  line-height: 1.75;
}

.entry-condition {
  margin-top: 8px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

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

.reading-col {
  padding: 20px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.reading-heading {
  padding-bottom: 10px;
  margin-bottom: 12px;
  font-size: 15px;
  font-weight: 600;
  border-bottom: 1px solid var(--line);
}

.reading-list li {
  position: relative;
  padding-left: 16px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

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

.reading-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 5px;
  height: 5px;
  background: var(--accent);
  border-radius: 50%;
}

.sidebar-block + .sidebar-block {
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}

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

.sidebar-list li {
  padding: 8px 0;
}

.sidebar-list a {
  display: block;
  min-height: 24px;
  color: var(--ink-soft);
  font-size: 14px;
}

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

/* 内页 — 使用指南 */

.guide-overview {
  margin-bottom: 8px;
}

.guide-figure {
  margin-top: 20px;
}

.guide-note {
  margin-top: 16px;
  color: var(--ink-soft);
  font-size: 15px;
  line-height: 1.75;
}

.prepare-columns {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 28px;
  margin-top: 20px;
}

.prepare-conditions,
.prepare-notes {
  min-width: 0;
  padding: 20px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.subsection-title {
  padding-bottom: 10px;
  margin-bottom: 12px;
  font-size: 15px;
  font-weight: 600;
  border-bottom: 1px solid var(--line);
}

.condition-item + .condition-item {
  margin-top: 12px;
}

.condition-name {
  font-size: 14px;
  font-weight: 600;
}

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

.prepare-notes p {
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.75;
}

.prepare-notes p + p {
  margin-top: 10px;
}

.step-list {
  counter-reset: step;
  margin-top: 20px;
  border-top: 1px solid var(--line);
}

.step-item {
  padding: 20px 0 20px 0;
  border-bottom: 1px solid var(--line);
}

.step-title {
  font-size: 16px;
  font-weight: 600;
}

.step-desc {
  margin-top: 8px;
  font-size: 15px;
  line-height: 1.75;
}

.step-deviation {
  margin-top: 8px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

.checkpoint-columns {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 28px;
  margin-top: 20px;
}

.checkpoint-items,
.checkpoint-methods {
  min-width: 0;
  padding: 20px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.checkpoint-list li,
.method-list li {
  position: relative;
  padding-left: 16px;
  font-size: 14px;
  line-height: 1.7;
}

.checkpoint-list li + li,
.method-list li + li {
  margin-top: 10px;
}

.checkpoint-list li::before,
.method-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
}

.checkpoint-list li::before {
  background: var(--accent);
}

.method-list li::before {
  background: var(--line);
}

.method-list li {
  color: var(--ink-soft);
}

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

.next-card {
  display: block;
  padding: 20px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--ink);
  text-decoration: none;
  transition: border-color 0.18s ease, background-color 0.18s ease;
}

.next-card:hover,
.next-card:focus-visible {
  border-color: var(--accent);
  background: #fbfdfc;
  color: var(--ink);
  text-decoration: none;
}

.next-card-title {
  font-size: 16px;
  font-weight: 600;
}

.next-card-desc {
  margin-top: 8px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

.side-link-list {
  margin-top: 14px;
}

.side-link-item {
  padding: 9px 0;
  border-top: 1px solid var(--line);
}

.side-link-item:last-child {
  border-bottom: 1px solid var(--line);
}

.side-link-item a {
  display: block;
  min-height: 24px;
  font-size: 14px;
  font-weight: 600;
}

.side-note {
  margin-top: 16px;
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.7;
}

/* 内页 — 常见问题 */

.content-figure {
  margin-bottom: 40px;
}

.faq-group {
  margin-top: 44px;
}

.faq-group:first-of-type {
  margin-top: 0;
}

.faq-item {
  margin-top: 12px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 18px;
  min-height: 44px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
}

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

.faq-question::after {
  content: "＋";
  flex: 0 0 auto;
  color: var(--accent);
  font-size: 15px;
  font-weight: 400;
}

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

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

.faq-answer {
  padding: 14px 18px 18px;
}

.faq-answer p {
  color: var(--ink-soft);
  font-size: 15px;
  line-height: 1.75;
}

.faq-answer p + p {
  margin-top: 10px;
}

.limits-section,
.feedback-section {
  margin-top: 44px;
}

.limits-item {
  position: relative;
  padding: 14px 0 14px 18px;
  border-top: 1px solid var(--line);
  font-size: 15px;
  line-height: 1.75;
}

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

.limits-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 22px;
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
}

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

.feedback-card {
  padding: 20px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.feedback-title {
  font-size: 16px;
  font-weight: 600;
}

.feedback-desc {
  margin-top: 8px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

.aside-block {
  margin-top: 22px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
}

.aside-subtitle {
  margin-bottom: 10px;
  font-size: 14px;
  font-weight: 600;
}

.copy-link {
  display: block;
  width: 100%;
  margin-top: 20px;
  padding: 11px 16px;
  min-height: 44px;
  color: var(--accent);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 600;
  transition: border-color 0.18s ease, color 0.18s ease;
}

.copy-link:hover,
.copy-link:focus-visible {
  border-color: var(--accent);
  color: var(--accent-dark);
}

/* ============================================================
   pages — 404
   ============================================================ */

.error-main {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 56px 24px 80px;
}

.error-hero {
  max-width: var(--read);
  padding-bottom: 28px;
  border-bottom: 1px solid var(--line);
}

.error-code {
  color: var(--accent);
  font-size: 14px;
  font-weight: 600;
}

.error-hero h1 {
  margin-top: 8px;
  font-size: 32px;
}

.error-lead {
  margin-top: 12px;
  color: var(--ink-soft);
  font-size: 16px;
}

.error-paths {
  margin-top: 40px;
}

.error-paths h2 {
  font-size: 22px;
}

.error-path-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
  margin-top: 20px;
}

.error-path-item {
  padding: 20px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.error-path-item h3 {
  font-size: 16px;
  font-weight: 600;
}

.error-path-item p {
  margin-top: 8px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

.error-path-link {
  display: inline-block;
  margin-top: 12px;
  min-height: 32px;
  font-size: 14px;
  font-weight: 600;
}

.error-back {
  margin-top: 40px;
  padding: 24px 22px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.error-back h2 {
  font-size: 18px;
}

.error-back p {
  margin-top: 8px;
  margin-bottom: 18px;
  color: var(--ink-soft);
  font-size: 15px;
}

.error-note {
  margin-top: 32px;
  max-width: var(--read);
}

.error-note h2 {
  font-size: 18px;
}

.error-note p {
  margin-top: 8px;
  color: var(--ink-soft);
  font-size: 15px;
  line-height: 1.75;
}

.error-text-link {
  display: inline-block;
  margin-top: 10px;
  min-height: 32px;
  font-size: 15px;
  font-weight: 600;
}

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

@media (max-width: 960px) {
  .header-inner {
    flex-wrap: wrap;
    gap: 12px;
    padding: 12px 20px;
  }

  .nav-toggle {
    display: flex;
    order: 3;
  }

  .site-nav {
    order: 4;
    flex: 1 1 100%;
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px 0 4px;
  }

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

  .nav-link {
    display: block;
    padding: 11px 6px;
    min-height: 44px;
    border-bottom: 1px solid var(--line);
    border-left: 2px solid transparent;
  }

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

  .hero-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 32px;
    padding: 40px 20px 44px;
  }

  .hero-select {
    max-width: none;
  }

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

  .path-grid,
  .topic-grid,
  .next-actions,
  .feedback-paths,
  .error-path-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .changes-index {
    position: static;
  }

  .section {
    padding: 44px 20px 0;
  }

  .section-limits {
    padding-bottom: 56px;
  }

  .inner-main {
    padding: 20px 20px 56px;
  }

  .page-layout,
  .layout-with-aside,
  .layout-shell {
    grid-template-columns: minmax(0, 1fr);
    gap: 36px;
  }

  .footer-inner {
    gap: 28px;
    padding: 36px 20px 26px;
  }

  .footer-about {
    flex: 1 1 100%;
    max-width: none;
  }

  .footer-nav {
    flex: 1 1 100%;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 22px;
  }

  .footer-bottom {
    padding: 16px 20px 26px;
  }

  .error-main {
    padding: 40px 20px 64px;
  }
}

@media (max-width: 640px) {
  body.site-body {
    font-size: 15px;
  }

  .brand-slogan {
    font-size: 16px;
  }

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

  .section-title,
  .error-paths h2 {
    font-size: 19px;
  }

  .hero-choices,
  .column-grid,
  .path-grid,
  .pick-sub-grid,
  .topic-grid,
  .reading-grid,
  .prepare-columns,
  .checkpoint-columns,
  .next-actions,
  .feedback-paths,
  .error-path-list,
  .footer-nav {
    grid-template-columns: minmax(0, 1fr);
  }

  .hero-cta-line {
    flex-direction: column;
    align-items: stretch;
  }

  .hero-cta-line .btn,
  .hero-cta-line .btn-primary,
  .hero-cta-line .btn-ghost {
    display: block;
    width: 100%;
  }

  .column-card,
  .path-card,
  .pick-main,
  .pick-sub,
  .topic-card,
  .reading-col,
  .prepare-conditions,
  .prepare-notes,
  .checkpoint-items,
  .checkpoint-methods,
  .feedback-card,
  .next-card,
  .error-path-item {
    padding: 18px 16px;
  }

  .limits-body {
    padding: 20px 16px;
  }

  .content-aside,
  .sidebar,
  .layout-side,
  .layout-aside {
    padding: 20px 16px;
  }

  .faq-question {
    padding: 14px 16px;
  }

  .faq-answer {
    padding: 12px 16px 16px;
  }

  .field-table,
  .spec-table {
    min-width: 520px;
  }

  .field-table th,
  .field-table td,
  .spec-table th,
  .spec-table td {
    padding: 10px 12px;
  }
}

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

  .btn,
  .btn-primary,
  .btn-ghost,
  .link-arrow,
  .choice-item,
  .next-card,
  .copy-link {
    transition: none;
  }
}