/* ==========================================================================
   BASE — 全站基础
   ========================================================================== */

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", "Helvetica Neue", Arial, sans-serif;
  font-size: 15px;
  line-height: 1.75;
  color: #1c1c1e;
  background-color: #f4f2ee;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  color: #b0683c;
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: #8a4e2a;
}

ul,
ol {
  list-style: none;
}

button {
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
  border: none;
  background: none;
  cursor: pointer;
}

details summary {
  cursor: pointer;
  list-style: none;
}

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

/* ==========================================================================
   LAYOUT — 全站骨架
   ========================================================================== */

.site-body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.site-header {
  background-color: #1c1c1e;
  border-bottom: 3px solid #b0683c;
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px;
  height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: flex;
  align-items: center;
  flex-shrink: 0;
  color: #ffffff;
}

.brand:hover {
  color: #ffffff;
}

.brand-name {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: #ffffff;
}

.brand-name::after {
  content: "论坛";
  font-size: 13px;
  font-weight: 400;
  color: #b0683c;
  margin-left: 6px;
  letter-spacing: 0.02em;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 10px;
  align-items: center;
}

.nav-toggle-bar {
  display: block;
  width: 22px;
  height: 2px;
  background-color: #ffffff;
  transition: transform 0.25s ease, opacity 0.25s ease;
}

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

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

.nav-item {
  margin: 0;
}

.nav-link {
  display: block;
  padding: 8px 16px;
  font-size: 15px;
  color: #d8d4cc;
  border-bottom: 2px solid transparent;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.nav-link:hover {
  color: #ffffff;
  border-bottom-color: #b0683c;
}

.nav-link.is-current {
  color: #ffffff;
  border-bottom-color: #b0683c;
  font-weight: 600;
}

.site-main {
  flex: 1 0 auto;
}

.inner-main {
  max-width: 1180px;
  margin: 0 auto;
  padding: 32px 24px 64px;
}

.site-footer {
  background-color: #1c1c1e;
  color: #c9c4bb;
  margin-top: auto;
}

.footer-inner {
  max-width: 1180px;
  margin: 0 auto;
  padding: 48px 24px 40px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
}

.footer-col h2 {
  font-size: 15px;
  font-weight: 600;
  color: #ffffff;
  margin-bottom: 16px;
  letter-spacing: 0.03em;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer-links a {
  font-size: 14px;
  color: #a39e94;
  transition: color 0.2s ease;
}

.footer-links a:hover {
  color: #ffffff;
}

.footer-col p {
  font-size: 14px;
  line-height: 1.7;
  color: #a39e94;
}

.footer-col .footer-note {
  margin-top: 12px;
  font-size: 13px;
  color: #7d786f;
}

/* ==========================================================================
   COMPONENTS — 通用组件
   ========================================================================== */

/* 面包屑 */
.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 14px;
  color: #8a7f74;
  margin-bottom: 20px;
}

.breadcrumb a {
  color: #8a7f74;
}

.breadcrumb a:hover {
  color: #b0683c;
}

.breadcrumb-sep {
  color: #b9b2a8;
}

.breadcrumb-current {
  color: #1c1c1e;
  font-weight: 500;
}

/* 页面标题区 */
.page-header {
  margin-bottom: 40px;
}

.page-title {
  font-size: 32px;
  line-height: 1.3;
  font-weight: 700;
  color: #1c1c1e;
  margin-bottom: 12px;
  letter-spacing: 0.01em;
}

.page-description {
  font-size: 16px;
  line-height: 1.7;
  color: #5c574f;
  max-width: 720px;
}

/* 区块标题 */
.section-title {
  font-size: 24px;
  line-height: 1.4;
  font-weight: 700;
  color: #1c1c1e;
  margin-bottom: 20px;
}

/* 主按钮 */
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 12px 28px;
  background-color: #b0683c;
  color: #ffffff;
  font-size: 16px;
  font-weight: 600;
  border-radius: 4px;
  transition: background-color 0.2s ease;
}

.btn-primary:hover {
  background-color: #8a4e2a;
  color: #ffffff;
}

/* 次按钮 */
.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 12px 28px;
  background-color: transparent;
  color: #b0683c;
  font-size: 16px;
  font-weight: 600;
  border: 1px solid #b0683c;
  border-radius: 4px;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.btn-secondary:hover {
  background-color: #b0683c;
  color: #ffffff;
}

/* 侧栏卡片 */
.sidebar-card {
  background-color: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 6px;
  padding: 24px;
}

.sidebar-card + .sidebar-card {
  margin-top: 20px;
}

.sidebar-card h2,
.sidebar-title {
  font-size: 18px;
  font-weight: 600;
  color: #1c1c1e;
  margin-bottom: 14px;
  line-height: 1.5;
}

.sidebar-card p {
  font-size: 14px;
  line-height: 1.7;
  color: #5c574f;
}

.sidebar-card a {
  font-size: 14px;
  font-weight: 500;
}

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

.sidebar-list a {
  display: inline-block;
  color: #5c574f;
  transition: color 0.2s ease;
}

.sidebar-list a:hover {
  color: #b0683c;
}

.sidebar-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.sidebar-links a {
  display: inline-block;
  color: #5c574f;
  font-size: 14px;
}

.sidebar-links a:hover {
  color: #b0683c;
}

/* 布局壳 */
.layout-shell {
  display: flex;
  align-items: flex-start;
  gap: 32px;
}

.layout-shell .main-content {
  flex: 1 1 auto;
  min-width: 0;
}

.layout-shell .sidebar-content,
.layout-shell .sidebar-area {
  flex: 0 0 300px;
  max-width: 300px;
}

.sidebar-right .main-content {
  order: 1;
}

.sidebar-right .sidebar-content {
  order: 2;
}

.sidebar-left .sidebar-area {
  order: 1;
}

.sidebar-left .content-area {
  order: 2;
  flex: 1 1 auto;
  min-width: 0;
}

/* 页面布局（帮助中心、守则） */
.page-layout {
  display: flex;
  align-items: flex-start;
  gap: 32px;
}

.page-layout .main-content {
  flex: 1 1 auto;
  min-width: 0;
}

.page-layout .sidebar-right,
.page-layout .sidebar-content {
  flex: 0 0 300px;
  max-width: 300px;
}

/* ==========================================================================
   COMPONENTS — 首页模块
   ========================================================================== */

/* 首屏 */
.hero-section {
  background-color: #1c1c1e;
  color: #ffffff;
}

.hero-inner {
  max-width: 1180px;
  margin: 0 auto;
  padding: 72px 24px 56px;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 56px;
  align-items: center;
}

.hero-copy h1 {
  font-size: 36px;
  line-height: 1.25;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 20px;
}

.hero-copy p {
  font-size: 16px;
  line-height: 1.75;
  color: #c9c4bb;
  margin-bottom: 12px;
}

.hero-media {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.hero-figure {
  border-radius: 6px;
  overflow: hidden;
}

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

.hero-media .btn-primary {
  align-self: flex-start;
}

/* 首屏下方图文说明 */
.content-media-primary {
  margin: 0 auto;
  max-width: 1180px;
  padding: 24px;
}

.content-media-primary img {
  width: 100%;
  aspect-ratio: 16 / 5;
  object-fit: cover;
  border-radius: 6px;
}

.content-media-primary figcaption {
  font-size: 14px;
  color: #8a7f74;
  margin-top: 8px;
  text-align: center;
}

/* 参与流程 */
.process-section {
  max-width: 1180px;
  margin: 0 auto;
  padding: 48px 24px;
}

.process-steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.step-item {
  background-color: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 6px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.step-status {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: 3px;
  align-self: flex-start;
}

.step-status.is-done {
  background-color: #e8e4dc;
  color: #5c574f;
}

.step-status.is-done::after {
  content: "已完成";
}

.step-status.is-current {
  background-color: #b0683c;
  color: #ffffff;
}

.step-status.is-current::after {
  content: "当前步骤";
}

.step-status.is-todo {
  background-color: #e8e4dc;
  color: #5c574f;
}

.step-status.is-todo::after {
  content: "下一步";
}

.step-number {
  font-size: 32px;
  font-weight: 700;
  color: #b0683c;
  line-height: 1.2;
}

.step-item p {
  font-size: 15px;
  color: #5c574f;
}

/* 版块矩阵 */
.board-grid-section {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px 48px;
}

.board-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.board-card {
  background-color: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 6px;
  padding: 28px 24px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  transition: box-shadow 0.25s ease, transform 0.25s ease;
}

.board-card:hover {
  box-shadow: 0 4px 16px rgba(28, 28, 30, 0.08);
  transform: translateY(-2px);
}

.board-card h3 {
  font-size: 18px;
  font-weight: 600;
  color: #1c1c1e;
  line-height: 1.5;
}

.board-card p {
  font-size: 14px;
  line-height: 1.7;
  color: #5c574f;
  flex: 1 1 auto;
}

.board-card a {
  font-size: 14px;
  font-weight: 500;
}

/* 首页两栏：最近话题 + 侧栏 */
.home-columns {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px 48px;
  display: flex;
  align-items: flex-start;
  gap: 32px;
}

.topic-list-panel {
  flex: 1 1 auto;
  min-width: 0;
  background-color: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 6px;
  padding: 28px 24px;
}

.topic-list-panel .section-title {
  margin-bottom: 16px;
}

.topic-list {
  display: flex;
  flex-direction: column;
}

.topic-item {
  padding: 20px 0;
  border-bottom: 1px solid #eeeae3;
}

.topic-item:first-child {
  padding-top: 0;
}

.topic-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.topic-board {
  display: inline-block;
  font-size: 13px;
  color: #b0683c;
  background-color: #f4f2ee;
  padding: 2px 10px;
  border-radius: 3px;
  margin-bottom: 8px;
}

.topic-item h3 {
  font-size: 17px;
  font-weight: 600;
  line-height: 1.5;
  margin-bottom: 6px;
}

.topic-item h3 a {
  color: #1c1c1e;
}

.topic-item h3 a:hover {
  color: #b0683c;
}

.topic-item p {
  font-size: 14px;
  line-height: 1.7;
  color: #5c574f;
  margin-bottom: 8px;
}

.topic-link {
  font-size: 14px;
  font-weight: 500;
}

.home-sidebar {
  flex: 0 0 300px;
  max-width: 300px;
}

/* 近期动态预览 */
.updates-preview {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px 56px;
}

.updates-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.update-item {
  background-color: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 6px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.update-item h3 {
  font-size: 17px;
  font-weight: 600;
  color: #1c1c1e;
  line-height: 1.5;
}

.update-item p {
  font-size: 14px;
  line-height: 1.7;
  color: #5c574f;
  flex: 1 1 auto;
}

.update-item a {
  font-size: 14px;
  font-weight: 500;
}

/* ==========================================================================
   COMPONENTS — 新手指南页
   ========================================================================== */

.intro-block {
  margin-bottom: 48px;
}

.intro-block .section-title {
  margin-bottom: 12px;
}

.intro-block > p {
  font-size: 15px;
  color: #5c574f;
  margin-bottom: 16px;
  max-width: 720px;
}

.intro-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding-left: 20px;
  list-style: disc;
}

.intro-list li {
  font-size: 15px;
  line-height: 1.7;
  color: #1c1c1e;
  padding-left: 4px;
}

.guide-media-block {
  margin-bottom: 48px;
}

.guide-media-block .section-title {
  margin-bottom: 12px;
}

.guide-media-block > p {
  font-size: 15px;
  color: #5c574f;
  margin-bottom: 16px;
  max-width: 720px;
}

.guide-figure {
  margin-bottom: 16px;
  border-radius: 6px;
  overflow: hidden;
}

.guide-figure img {
  width: 100%;
  aspect-ratio: 16 / 7;
  object-fit: cover;
}

.guide-figure figcaption {
  font-size: 14px;
  color: #8a7f74;
  padding: 8px 0;
  border-bottom: 1px solid #e2ddd5;
}

.guide-edit-block {
  margin-bottom: 48px;
}

.guide-edit-block .section-title {
  margin-bottom: 12px;
}

.guide-edit-block > p {
  font-size: 15px;
  color: #5c574f;
  margin-bottom: 16px;
  max-width: 720px;
}

.operation-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding-left: 20px;
  list-style: decimal;
  margin-bottom: 16px;
}

.operation-list li {
  font-size: 15px;
  line-height: 1.7;
  color: #1c1c1e;
  padding-left: 4px;
}

/* 步骤进度导航 */
.progress-nav {
  margin-bottom: 48px;
  background-color: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 6px;
  padding: 28px 24px;
}

.progress-nav .section-title {
  margin-bottom: 20px;
}

.progress-steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.progress-steps .step-item {
  border: 1px solid #e2ddd5;
  border-radius: 6px;
  padding: 20px;
  display: flex;
  align-items: center;
  gap: 14px;
}

.progress-steps .step-item.is-done {
  background-color: #f4f2ee;
}

.progress-steps .step-item.is-current {
  background-color: #f4f2ee;
  border-color: #b0683c;
}

.progress-steps .step-item.is-todo {
  background-color: #ffffff;
}

.step-num {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background-color: #e2ddd5;
  color: #5c574f;
  font-size: 15px;
  font-weight: 700;
  flex-shrink: 0;
}

.progress-steps .step-item.is-done .step-num {
  background-color: #8a7f74;
  color: #ffffff;
}

.progress-steps .step-item.is-current .step-num {
  background-color: #b0683c;
  color: #ffffff;
}

.progress-steps .step-item.is-todo .step-num {
  background-color: #e8e4dc;
  color: #8a7f74;
}

.step-text {
  font-size: 15px;
  font-weight: 500;
  color: #1c1c1e;
}

/* 相关入口 */
.related-links {
  margin-top: 48px;
}

.related-links .section-title {
  margin-bottom: 12px;
}

.related-links > p {
  font-size: 15px;
  color: #5c574f;
  margin-bottom: 20px;
  max-width: 720px;
}

.link-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.link-card {
  background-color: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 6px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.link-card h3 {
  font-size: 17px;
  font-weight: 600;
  color: #1c1c1e;
  line-height: 1.5;
}

.link-card p {
  font-size: 14px;
  line-height: 1.7;
  color: #5c574f;
  flex: 1 1 auto;
}

.link-card a {
  font-size: 14px;
  font-weight: 500;
}

/* ==========================================================================
   COMPONENTS — 话题广场页
   ========================================================================== */

.section-filter {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 32px;
}

.filter-tag {
  display: inline-block;
  padding: 8px 18px;
  font-size: 14px;
  font-weight: 500;
  background-color: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 4px;
  color: #5c574f;
  transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.filter-tag:hover {
  border-color: #b0683c;
  color: #b0683c;
}

.filter-tag.is-active {
  background-color: #b0683c;
  border-color: #b0683c;
  color: #ffffff;
}

.page-header-media {
  margin-top: 20px;
  border-radius: 6px;
  overflow: hidden;
}

.page-header-media img {
  width: 100%;
  aspect-ratio: 16 / 5;
  object-fit: cover;
}

.section-desc {
  font-size: 15px;
  color: #5c574f;
  margin-bottom: 24px;
  max-width: 720px;
}

.topic-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.topic-item {
  padding: 24px 0;
  border-bottom: 1px solid #eeeae3;
}

.topic-item:first-child {
  padding-top: 0;
}

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

.topic-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 8px;
}

.topic-board {
  display: inline-block;
  font-size: 13px;
  color: #b0683c;
  background-color: #f4f2ee;
  padding: 2px 10px;
  border-radius: 3px;
}

.topic-date {
  font-size: 13px;
  color: #8a7f74;
}

.topic-title {
  font-size: 18px;
  font-weight: 600;
  line-height: 1.5;
  margin-bottom: 8px;
}

.topic-title a {
  color: #1c1c1e;
}

.topic-title a:hover {
  color: #b0683c;
}

.topic-summary {
  font-size: 14px;
  line-height: 1.7;
  color: #5c574f;
  margin-bottom: 10px;
}

.topic-link {
  font-size: 14px;
  font-weight: 500;
}

/* 分页 */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  padding: 32px 0 8px;
}

.page-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 44px;
  height: 44px;
  padding: 0 18px;
  background-color: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 4px;
  font-size: 14px;
  font-weight: 500;
  color: #1c1c1e;
  transition: border-color 0.2s ease, color 0.2s ease;
}

.page-link:hover {
  border-color: #b0683c;
  color: #b0683c;
}

.page-link.prev::before {
  content: "←";
  margin-right: 6px;
}

.page-link.next::after {
  content: "→";
  margin-left: 6px;
}

.page-indicator {
  font-size: 14px;
  color: #8a7f74;
}

.load-more {
  display: block;
  margin: 20px auto 0;
  min-height: 48px;
  padding: 12px 36px;
  background-color: transparent;
  border: 1px solid #b0683c;
  border-radius: 4px;
  color: #b0683c;
  font-size: 15px;
  font-weight: 500;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.load-more:hover {
  background-color: #b0683c;
  color: #ffffff;
}

/* 话题广场相关链接条 */
.related-links {
  margin-top: 40px;
  padding-top: 20px;
  border-top: 1px solid #e2ddd5;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

.related-links-label {
  font-size: 14px;
  font-weight: 600;
  color: #1c1c1e;
}

.related-links-item {
  font-size: 14px;
  color: #5c574f;
}

.related-links-item:hover {
  color: #b0683c;
}

/* ==========================================================================
   COMPONENTS — 动态记录页
   ========================================================================== */

.year-index-card {
  position: sticky;
  top: 88px;
}

.year-index-list {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.year-index-list a {
  display: block;
  padding: 10px 12px;
  font-size: 15px;
  font-weight: 500;
  color: #1c1c1e;
  border-radius: 4px;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.year-index-list a:hover {
  background-color: #f4f2ee;
  color: #b0683c;
}

.timeline-section {
  margin-bottom: 48px;
}

.timeline-section > h2 {
  font-size: 24px;
  font-weight: 700;
  color: #1c1c1e;
  margin-bottom: 20px;
  padding-bottom: 10px;
  border-bottom: 2px solid #1c1c1e;
}

.month-group {
  margin-bottom: 32px;
}

.month-group h3 {
  font-size: 17px;
  font-weight: 600;
  color: #b0683c;
  margin-bottom: 14px;
}

.timeline-item {
  display: flex;
  gap: 20px;
  padding: 16px 0;
  border-bottom: 1px solid #eeeae3;
}

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

.timeline-figure {
  flex: 0 0 120px;
  border-radius: 4px;
  overflow: hidden;
}

.timeline-figure img {
  width: 120px;
  height: 80px;
  object-fit: cover;
}

.timeline-content {
  flex: 1 1 auto;
  min-width: 0;
}

.timeline-content h4 {
  font-size: 16px;
  font-weight: 600;
  color: #1c1c1e;
  margin-bottom: 6px;
  line-height: 1.5;
}

.timeline-content h4 a {
  color: #1c1c1e;
}

.timeline-content h4 a:hover {
  color: #b0683c;
}

.timeline-summary {
  font-size: 14px;
  line-height: 1.7;
  color: #5c574f;
}

.timeline-tag {
  display: inline-block;
  font-size: 13px;
  color: #8a7f74;
  background-color: #f4f2ee;
  padding: 2px 10px;
  border-radius: 3px;
  margin-bottom: 8px;
}

/* 历史跳转 */
.history-jump-section {
  margin-top: 48px;
  padding: 32px;
  background-color: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 6px;
}

.history-jump-section h2 {
  font-size: 20px;
  font-weight: 600;
  color: #1c1c1e;
  margin-bottom: 12px;
}

.history-jump-section > p {
  font-size: 15px;
  color: #5c574f;
  margin-bottom: 16px;
}

.history-jump {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.history-jump a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 10px 20px;
  background-color: #f4f2ee;
  border: 1px solid #e2ddd5;
  border-radius: 4px;
  font-size: 14px;
  font-weight: 500;
  color: #1c1c1e;
  transition: border-color 0.2s ease, color 0.2s ease;
}

.history-jump a:hover {
  border-color: #b0683c;
  color: #b0683c;
}

/* ==========================================================================
   COMPONENTS — 帮助中心页
   ========================================================================== */

.help-intro {
  margin-bottom: 32px;
}

.help-intro .section-title {
  margin-bottom: 12px;
}

.help-intro p {
  font-size: 15px;
  color: #5c574f;
  max-width: 720px;
}

.faq-section {
  margin-bottom: 48px;
}

.faq-item {
  background-color: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 6px;
  margin-bottom: 12px;
  overflow: hidden;
}

.faq-item summary {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 18px 24px;
  font-size: 16px;
  font-weight: 500;
  color: #1c1c1e;
  transition: color 0.2s ease;
}

.faq-item summary::after {
  content: "+";
  font-size: 22px;
  font-weight: 400;
  color: #b0683c;
  flex-shrink: 0;
  transition: transform 0.25s ease;
}

.faq-item[open] summary::after {
  transform: rotate(45deg);
}

.faq-item summary:hover {
  color: #b0683c;
}

.faq-item p {
  padding: 0 24px 18px;
  font-size: 15px;
  line-height: 1.75;
  color: #5c574f;
}

.feedback-process {
  margin-bottom: 48px;
}

.feedback-process .section-title {
  margin-bottom: 12px;
}

.feedback-process > p {
  font-size: 15px;
  color: #5c574f;
  margin-bottom: 20px;
  max-width: 720px;
}

.process-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 20px;
}

.process-item {
  background-color: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 6px;
  padding: 20px;
}

.process-item h3 {
  font-size: 16px;
  font-weight: 600;
  color: #1c1c1e;
  margin-bottom: 8px;
}

.process-item h3::before {
  content: attr(data-step);
  display: inline-block;
  margin-right: 8px;
  color: #b0683c;
}

.process-item p {
  font-size: 14px;
  line-height: 1.7;
  color: #5c574f;
}

.feedback-process a {
  font-size: 15px;
  font-weight: 500;
}

.help-media {
  margin-top: 40px;
  border-radius: 6px;
  overflow: hidden;
}

.help-media img {
  width: 100%;
  aspect-ratio: 16 / 6;
  object-fit: cover;
}

.help-media figcaption {
  font-size: 14px;
  color: #8a7f74;
  padding: 8px 0;
}

/* ==========================================================================
   COMPONENTS — 社区守则页
   ========================================================================== */

.rule-figure {
  margin-bottom: 32px;
  border-radius: 6px;
  overflow: hidden;
}

.rule-figure img {
  width: 100%;
  aspect-ratio: 16 / 5;
  object-fit: cover;
}

.rule-section {
  margin-bottom: 40px;
}

.rule-section h2 {
  font-size: 20px;
  font-weight: 600;
  color: #1c1c1e;
  margin-bottom: 12px;
}

.rule-intro {
  font-size: 15px;
  color: #5c574f;
  margin-bottom: 16px;
  max-width: 720px;
}

.rule-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding-left: 20px;
  list-style: disc;
}

.rule-list li {
  font-size: 15px;
  line-height: 1.7;
  color: #1c1c1e;
  padding-left: 4px;
}

.rule-note {
  font-size: 14px;
  color: #8a7f74;
  margin-top: 16px;
  padding: 12px 16px;
  background-color: #f4f2ee;
  border-left: 3px solid #b0683c;
}

.rule-steps {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding-left: 20px;
  list-style: decimal;
}

.rule-steps li {
  font-size: 15px;
  line-height: 1.7;
  color: #1c1c1e;
  padding-left: 4px;
}

/* 相关入口 */
.related-title {
  font-size: 20px;
  font-weight: 600;
  color: #1c1c1e;
  margin-bottom: 20px;
}

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

.related-card {
  display: block;
  background-color: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 6px;
  padding: 24px;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.related-card:hover {
  border-color: #b0683c;
  box-shadow: 0 4px 12px rgba(28, 28, 30, 0.06);
}

.related-card h3 {
  font-size: 17px;
  font-weight: 600;
  color: #1c1c1e;
  margin-bottom: 8px;
}

.related-card p {
  font-size: 14px;
  line-height: 1.7;
  color: #5c574f;
}

/* ==========================================================================
   PAGES — 404 页
   ========================================================================== */

.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 60vh;
  padding: 48px 24px;
}

.error-section {
  max-width: 560px;
  text-align: center;
}

.error-code {
  font-size: 72px;
  font-weight: 700;
  color: #b0683c;
  line-height: 1.1;
  margin-bottom: 16px;
}

.error-section h1 {
  font-size: 28px;
  font-weight: 700;
  color: #1c1c1e;
  margin-bottom: 12px;
}

.error-desc {
  font-size: 16px;
  color: #5c574f;
  margin-bottom: 24px;
}

.error-actions {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 24px;
}

.error-help {
  font-size: 14px;
  color: #8a7f74;
}

/* ==========================================================================
   RESPONSIVE — 响应式
   ========================================================================== */

@media (max-width: 1024px) {
  .board-grid {
    grid-template-columns: repeat(2, 1fr);
  }

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

  .layout-shell {
    gap: 24px;
  }

  .layout-shell .sidebar-content,
  .layout-shell .sidebar-area {
    flex-basis: 260px;
    max-width: 260px;
  }

  .page-layout .sidebar-right,
  .page-layout .sidebar-content {
    flex-basis: 260px;
    max-width: 260px;
  }
}

@media (max-width: 768px) {
  .header-inner {
    height: 60px;
    padding: 0 16px;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: fixed;
    top: 60px;
    left: 0;
    right: 0;
    background-color: #1c1c1e;
    border-top: 1px solid #3a3a3d;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    padding: 8px 0;
  }

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

  .site-nav.is-open {
    max-height: 400px;
  }

  .nav-item {
    width: 100%;
  }

  .nav-link {
    padding: 14px 24px;
    border-bottom: none;
    border-left: 3px solid transparent;
  }

  .nav-link.is-current {
    border-left-color: #b0683c;
    border-bottom: none;
  }

  .hero-inner {
    grid-template-columns: 1fr;
    gap: 32px;
    padding: 48px 16px 40px;
  }

  .hero-copy h1 {
    font-size: 28px;
  }

  .process-steps {
    grid-template-columns: 1fr;
  }

  .board-grid {
    grid-template-columns: 1fr;
  }

  .home-columns {
    flex-direction: column;
    padding: 0 16px 40px;
  }

  .topic-list-panel {
    order: 1;
    padding: 24px 16px;
  }

  .home-sidebar {
    order: 2;
    flex-basis: auto;
    max-width: none;
    width: 100%;
  }

  .updates-grid {
    grid-template-columns: 1fr;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 32px;
    padding: 40px 16px 32px;
  }

  .inner-main {
    padding: 24px 16px 48px;
  }

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

  .section-title {
    font-size: 21px;
  }

  .layout-shell {
    flex-direction: column;
  }

  .layout-shell .sidebar-content,
  .layout-shell .sidebar-area {
    flex-basis: auto;
    max-width: none;
    width: 100%;
    order: 2;
  }

  .layout-shell .main-content {
    order: 1;
    width: 100%;
  }

  .sidebar-left .sidebar-area {
    order: 2;
  }

  .sidebar-left .content-area {
    order: 1;
    width: 100%;
  }

  .page-layout {
    flex-direction: column;
  }

  .page-layout .main-content {
    order: 1;
    width: 100%;
  }

  .page-layout .sidebar-right,
  .page-layout .sidebar-content {
    order: 2;
    flex-basis: auto;
    max-width: none;
    width: 100%;
  }

  .link-cards {
    grid-template-columns: 1fr;
  }

  .process-list {
    grid-template-columns: 1fr;
  }

  .related-grid {
    grid-template-columns: 1fr;
  }

  .progress-steps {
    grid-template-columns: 1fr;
  }

  .timeline-item {
    flex-direction: column;
    gap: 12px;
  }

  .timeline-figure {
    flex-basis: auto;
  }

  .timeline-figure img {
    width: 100%;
    height: auto;
    aspect-ratio: 16 / 9;
  }

  .year-index-card {
    position: static;
  }

  .section-filter {
    gap: 8px;
  }

  .filter-tag {
    padding: 8px 14px;
    font-size: 13px;
  }

  .page-header-media img {
    aspect-ratio: 16 / 8;
  }

  .content-media-primary img {
    aspect-ratio: 16 / 9;
  }

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

  .help-media img {
    aspect-ratio: 16 / 9;
  }

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

  .error-code {
    font-size: 56px;
  }

  .error-actions {
    flex-direction: column;
    align-items: center;
  }

  .error-actions .btn-primary,
  .error-actions .btn-secondary {
    width: 100%;
    max-width: 280px;
  }
}

@media (max-width: 480px) {
  .hero-copy h1 {
    font-size: 24px;
  }

  .hero-copy p {
    font-size: 15px;
  }

  .hero-media .btn-primary {
    width: 100%;
  }

  .topic-list-panel {
    padding: 20px 14px;
  }

  .topic-item h3 {
    font-size: 16px;
  }

  .footer-inner {
    gap: 28px;
  }

  .pagination {
    gap: 10px;
  }

  .page-link {
    min-width: 40px;
    height: 40px;
    padding: 0 14px;
  }

  .faq-item summary {
    padding: 16px;
    font-size: 15px;
  }

  .faq-item p {
    padding: 0 16px 16px;
  }

  .timeline-content h4 {
    font-size: 15px;
  }

  .history-jump {
    flex-direction: column;
  }

  .history-jump a {
    width: 100%;
    justify-content: center;
  }
}

/* ==========================================================================
   ANIMATION — 轻量动效增强
   ========================================================================== */

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.board-card,
.update-item,
.link-card,
.related-card,
.process-item {
  animation: fadeInUp 0.4s ease both;
}

.board-card:nth-child(2),
.update-item:nth-child(2),
.link-card:nth-child(2),
.related-card:nth-child(2) {
  animation-delay: 0.06s;
}

.board-card:nth-child(3),
.update-item:nth-child(3),
.link-card:nth-child(3),
.related-card:nth-child(3) {
  animation-delay: 0.12s;
}

.board-card:nth-child(4),
.update-item:nth-child(4) {
  animation-delay: 0.18s;
}

@media (prefers-reduced-motion: reduce) {
  .board-card,
  .update-item,
  .link-card,
  .related-card,
  .process-item {
    animation: none;
  }
}