/* ==========================================================
   糖心love 论坛 — 全站样式表
   视觉方向：艺术展览风 / 中性浅米色 / 衬线标题 + 无衬线正文
   ========================================================== */

/* ==========================================================
   1. Base — 基础变量、重置与全局元素
   ========================================================== */

:root {
  /* 色彩系统 */
  --color-bg: #F4F1EC;
  --color-text: #26221D;
  --color-text-secondary: #6F675C;
  --color-accent: #B4593B;
  --color-accent-soft: #E8D9CE;
  --color-card: #FFFFFF;
  --color-border: #DCD6CC;
  --color-border-light: #E9E4DC;

  /* 字体 */
  --font-heading: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", serif;
  --font-body: "Inter", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;

  /* 尺寸 */
  --container-width: 1120px;
  --container-padding: 24px;
  --content-max: 760px;
  --radius: 8px;

  /* 间距 */
  --space-xs: 8px;
  --space-sm: 16px;
  --space-md: 28px;
  --space-lg: 48px;
  --space-xl: 72px;

  /* 过渡 */
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
}

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

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

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.8;
  color: var(--color-text);
  background-color: var(--color-bg);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

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

a:hover {
  color: #8F422B;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.4;
  color: var(--color-text);
}

ul, ol {
  list-style: none;
}

figure {
  margin: 0;
}

/* 辅助类：仅屏幕阅读器可见 */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ==========================================================
   2. Layout — 全站布局骨架
   ========================================================== */

.container,
.header-inner,
.footer-inner,
.inner-main,
.home-main {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
}

/* 主内容区域 */
.site-main {
  flex: 1 0 auto;
  width: 100%;
}

.home-main {
  padding-top: var(--space-lg);
  padding-bottom: var(--space-xl);
}

.inner-main {
  padding-top: var(--space-md);
  padding-bottom: var(--space-xl);
}

/* 内页统一宽度与间距 */
.inner-main .page-header {
  max-width: var(--container-width);
  margin: 0 auto;
}

/* 正文内容宽度约束 */
.inner-main .page-header + section,
.inner-main .page-header + .layout-shell {
  max-width: var(--container-width);
  margin-left: auto;
  margin-right: auto;
}

/* ==========================================================
   3. Components — 通用组件
   ========================================================== */

/* ---------- 页头 Header ---------- */

.site-header {
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  position: relative;
  z-index: 100;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 72px;
  gap: 24px;
  flex-wrap: wrap;
  padding-top: 12px;
  padding-bottom: 12px;
}

.brand {
  display: inline-flex;
  flex-direction: column;
  line-height: 1.3;
}

.brand-name {
  font-family: var(--font-heading);
  font-size: 22px;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: 0.02em;
}

.brand-slogan {
  font-size: 13px;
  color: var(--color-text-secondary);
  margin-top: 2px;
}

/* 主导航 */
.site-nav {
  display: flex;
  align-items: center;
  gap: 24px;
}

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

.nav-list li a {
  display: inline-block;
  padding: 8px 14px;
  font-size: 15px;
  color: var(--color-text);
  border-radius: var(--radius);
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

.nav-list li a:hover {
  color: var(--color-accent);
  background-color: rgba(180, 89, 59, 0.08);
}

.nav-list li a.is-current {
  color: var(--color-accent);
  background-color: rgba(180, 89, 59, 0.1);
  font-weight: 600;
}

/* 参与讨论按钮 */
.btn-participate {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 18px;
  background-color: var(--color-accent);
  color: #FFFFFF;
  border-radius: var(--radius);
  font-size: 15px;
  font-weight: 500;
  transition: background-color var(--transition-fast);
  white-space: nowrap;
}

.btn-participate:hover {
  background-color: #8F422B;
  color: #FFFFFF;
}

.btn-participate.is-current {
  background-color: #8F422B;
}

/* 汉堡菜单按钮（默认桌面隐藏） */
.nav-toggle {
  display: none;
  background: none;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  width: 44px;
  height: 44px;
  cursor: pointer;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  padding: 8px;
}

.nav-toggle-bar {
  display: block;
  width: 20px;
  height: 2px;
  background-color: var(--color-text);
  border-radius: 2px;
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

/* ---------- 面包屑 ---------- */

.breadcrumb {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-md);
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.breadcrumb a {
  color: var(--color-text-secondary);
}

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

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

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

/* ---------- 页面标题区 ---------- */

.page-header {
  margin-bottom: var(--space-lg);
}

.page-title {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 12px;
}

.page-description {
  font-size: 16px;
  color: var(--color-text-secondary);
  max-width: 680px;
  line-height: 1.8;
}

.page-header-figure,
.page-header-media {
  margin-top: var(--space-md);
  max-width: 100%;
  overflow: hidden;
  border-radius: var(--radius);
  background-color: var(--color-border-light);
}

.page-header-figure img,
.page-header-media img {
  width: 100%;
  height: 240px;
  object-fit: cover;
}

/* ---------- 页脚 Footer ---------- */

.site-footer {
  background-color: var(--color-bg);
  border-top: 1px solid var(--color-border-light);
  padding-top: var(--space-lg);
  margin-top: auto;
}

.footer-inner {
  display: grid;
  grid-template-columns: 1.2fr 1fr 1fr 1fr;
  gap: 40px;
  padding-bottom: var(--space-lg);
}

.footer-brand p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

.footer-brand strong {
  display: block;
  font-family: var(--font-heading);
  font-size: 18px;
  color: var(--color-text);
  margin-bottom: 8px;
}

.footer-nav h2 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--color-text);
  font-family: var(--font-body);
}

.footer-nav li {
  margin-bottom: 8px;
}

.footer-nav li a {
  font-size: 14px;
  color: var(--color-text-secondary);
}

.footer-nav li a:hover {
  color: var(--color-accent);
}

.footer-bottom {
  border-top: 1px solid var(--color-border-light);
  padding: var(--space-sm) 0;
  text-align: center;
}

.footer-bottom p {
  font-size: 13px;
  color: var(--color-text-secondary);
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

/* ---------- 区块通用 ---------- */

.section-block {
  margin-bottom: var(--space-xl);
}

.section-block h2 {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 8px;
}

.section-desc {
  font-size: 15px;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-md);
  max-width: 640px;
}

.section-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 15px;
  font-weight: 500;
  margin-top: var(--space-sm);
}

/* ==========================================================
   4. Pages — 页面级样式
   ========================================================== */

/* ---------- 首页 Hero ---------- */

.hero-section {
  margin-bottom: var(--space-xl);
}

.layout-split {
  display: grid;
  grid-template-columns: 62% 1fr;
  gap: 40px;
  align-items: start;
}

.hero-main h1 {
  font-size: 40px;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: var(--space-sm);
}

.hero-lead {
  font-size: 16px;
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: var(--space-md);
  max-width: 620px;
}

.hero-responsibilities {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-md);
  margin-bottom: var(--space-md);
}

.hero-responsibilities ul li {
  padding: 6px 0;
  font-size: 15px;
  display: flex;
  align-items: flex-start;
  gap: 10px;
}

.hero-responsibilities ul li::before {
  content: "";
  flex-shrink: 0;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--color-accent);
  margin-top: 11px;
}

.hero-figure {
  border-radius: var(--radius);
  overflow: hidden;
  background-color: var(--color-border-light);
}

.hero-figure img {
  width: 100%;
  height: 280px;
  object-fit: cover;
}

.hero-figure figcaption {
  font-size: 13px;
  color: var(--color-text-secondary);
  padding: 10px 14px;
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-top: none;
  border-radius: 0 0 var(--radius) var(--radius);
}

/* 公告卡 */
.hero-aside {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-md);
}

.notice-card h2 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 12px;
  font-family: var(--font-body);
}

.notice-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-sm);
  line-height: 1.7;
}

.notice-card a {
  display: inline-block;
  font-size: 14px;
  font-weight: 500;
  margin-top: 6px;
  margin-right: 16px;
}

/* ---------- 首页版块导航带 ---------- */

.board-nav-section {
  padding: var(--space-lg) 0;
  border-top: 1px solid var(--color-border-light);
  border-bottom: 1px solid var(--color-border-light);
}

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

.board-card {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  overflow: hidden;
  transition: box-shadow var(--transition-normal), transform var(--transition-normal);
  display: flex;
  flex-direction: column;
}

.board-card:hover {
  box-shadow: 0 4px 20px rgba(38, 34, 29, 0.08);
  transform: translateY(-2px);
}

.board-card img {
  width: 100%;
  height: 140px;
  object-fit: cover;
}

.board-card h3 {
  font-size: 18px;
  font-weight: 600;
  padding: var(--space-sm) var(--space-sm) 4px;
  font-family: var(--font-heading);
}

.board-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  padding: 0 var(--space-sm);
  flex: 1 0 auto;
  line-height: 1.7;
}

.board-card a {
  display: inline-flex;
  align-items: center;
  font-size: 14px;
  font-weight: 500;
  padding: 8px var(--space-sm) var(--space-sm);
}

/* ---------- 首页热门话题 ---------- */

.topic-list {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  overflow: hidden;
}

.topic-item {
  padding: var(--space-sm) var(--space-md);
  border-bottom: 1px solid var(--color-border-light);
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 8px 16px;
  align-items: baseline;
  transition: background-color var(--transition-fast);
}

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

.topic-item:hover {
  background-color: rgba(244, 241, 236, 0.6);
}

.topic-item a {
  display: inline-block;
}

.topic-item a h3 {
  font-size: 16px;
  font-weight: 600;
  font-family: var(--font-body);
  transition: color var(--transition-fast);
}

.topic-item a:hover h3 {
  color: var(--color-accent);
}

.topic-board {
  font-size: 13px;
  color: var(--color-text-secondary);
  background-color: var(--color-bg);
  padding: 2px 10px;
  border-radius: 4px;
  white-space: nowrap;
  align-self: center;
}

.topic-item p {
  font-size: 14px;
  color: var(--color-text-secondary);
  grid-column: 1 / -1;
  line-height: 1.7;
}

.topic-tag {
  display: inline-block;
  font-size: 12px;
  color: var(--color-accent);
  background-color: rgba(180, 89, 59, 0.08);
  padding: 2px 10px;
  border-radius: 4px;
  grid-column: 1 / -1;
  width: fit-content;
}

/* ---------- 首页参与路径 ---------- */

.path-steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  counter-reset: path-step;
}

.path-step {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-md);
  position: relative;
  counter-increment: path-step;
}

.path-step::before {
  content: counter(path-step, decimal-leading-zero);
  font-family: var(--font-heading);
  font-size: 14px;
  color: var(--color-accent);
  display: block;
  margin-bottom: 8px;
  font-weight: 600;
}

.path-step h3 {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 6px;
}

.path-step p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 10px;
  line-height: 1.7;
}

.path-step a {
  font-size: 14px;
  font-weight: 500;
}

/* ---------- 首页站务更新 ---------- */

.update-list {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  overflow: hidden;
}

.update-item {
  padding: var(--space-sm) var(--space-md);
  border-bottom: 1px solid var(--color-border-light);
}

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

.update-item h3 {
  font-size: 15px;
  font-weight: 600;
  font-family: var(--font-body);
  margin-bottom: 2px;
}

.update-item p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* ---------- 版块导航页 ---------- */

.section-forum-index {
  margin-bottom: var(--space-lg);
}

.section-forum-index > h2 {
  font-size: 24px;
  margin-bottom: var(--space-md);
}

.forum-group {
  margin-bottom: var(--space-md);
}

.forum-group-title {
  font-size: 18px;
  font-weight: 600;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--color-border);
  margin-bottom: var(--space-sm);
}

.forum-group-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.forum-row {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-sm) var(--space-md);
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 4px 16px;
  align-items: start;
  transition: box-shadow var(--transition-fast);
}

.forum-row:hover {
  box-shadow: 0 2px 12px rgba(38, 34, 29, 0.06);
}

.forum-name {
  font-size: 16px;
  font-weight: 600;
  font-family: var(--font-body);
}

.forum-desc {
  font-size: 14px;
  color: var(--color-text-secondary);
  grid-column: 1 / -1;
  line-height: 1.7;
}

.forum-topics {
  font-size: 13px;
  color: var(--color-text-secondary);
  grid-column: 1 / -1;
}

.forum-link {
  grid-column: 1 / -1;
  font-size: 14px;
  font-weight: 500;
  justify-self: start;
}

/* 参与提示条 */
.section-participate-tip {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-left: 3px solid var(--color-accent);
  border-radius: var(--radius);
  padding: var(--space-md);
  margin-bottom: var(--space-lg);
}

.section-participate-tip h2 {
  font-size: 18px;
  margin-bottom: 6px;
  font-family: var(--font-body);
}

.tip-text {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 10px;
}

.tip-links {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
}

.tip-links a {
  font-size: 14px;
  font-weight: 500;
}

/* 相关版块入口 */
.section-related-forum {
  margin-bottom: var(--space-lg);
}

.section-related-forum h2 {
  font-size: 20px;
  margin-bottom: 6px;
}

.related-desc {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-sm);
}

.related-links {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.related-links a {
  display: inline-block;
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: 8px 18px;
  font-size: 14px;
  font-weight: 500;
  transition: border-color var(--transition-fast), color var(--transition-fast);
}

.related-links a:hover {
  border-color: var(--color-accent);
}

/* ---------- 热门话题页 ---------- */

.layout-shell.page-layout {
  display: grid;
  grid-template-columns: 1fr 270px;
  gap: 40px;
  align-items: start;
  margin-bottom: var(--space-lg);
}

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

.topic-list-section {
  margin-bottom: var(--space-md);
}

.section-title {
  font-size: 24px;
  margin-bottom: 6px;
}

.section-intro {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-sm);
}

.topic-list-section .topic-item {
  padding: var(--space-sm) var(--space-md);
}

.topic-title {
  font-size: 17px;
  font-weight: 600;
  font-family: var(--font-body);
  margin-bottom: 2px;
}

.topic-title a {
  color: var(--color-text);
}

.topic-title a:hover {
  color: var(--color-accent);
}

.topic-meta {
  font-size: 13px;
  color: var(--color-text-secondary);
  margin-bottom: 6px;
}

.topic-meta a {
  font-size: 13px;
  font-weight: 500;
}

.topic-summary {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 8px;
}

.topic-tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.tag {
  display: inline-block;
  font-size: 12px;
  color: var(--color-accent);
  background-color: rgba(180, 89, 59, 0.08);
  padding: 2px 10px;
  border-radius: 4px;
}

/* 侧栏 */
.sidebar-column {
  min-width: 0;
}

.sidebar-column section {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-md);
  margin-bottom: var(--space-md);
}

.sidebar-title {
  font-size: 16px;
  font-weight: 600;
  font-family: var(--font-body);
  padding-bottom: 8px;
  border-bottom: 1px solid var(--color-border-light);
  margin-bottom: var(--space-sm);
}

.board-list li {
  margin-bottom: 8px;
}

.board-list li a {
  display: block;
  font-size: 14px;
  padding: 6px 10px;
  border-radius: 4px;
  transition: background-color var(--transition-fast);
}

.board-list li a:hover {
  background-color: var(--color-bg);
}

.rule-list li {
  margin-bottom: 8px;
}

.rule-list li a {
  font-size: 14px;
  display: inline-block;
  padding: 4px 0;
}

/* 参与提示（热门话题页底部） */
.participation-note {
  background-color: var(--color-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-sm) var(--space-md);
  margin-top: var(--space-md);
}

.participation-note p {
  font-size: 14px;
  color: var(--color-text-secondary);
}

.participation-note a {
  font-weight: 500;
  margin: 0 4px;
}

/* ---------- 发帖指南页 ---------- */

.guide-section {
  max-width: var(--content-max);
  margin-bottom: var(--space-lg);
}

.guide-section h2 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: var(--space-sm);
  padding-bottom: 8px;
  border-bottom: 1px solid var(--color-border-light);
}

.guide-section > p {
  font-size: 15px;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-sm);
}

.audience-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.audience-card {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-sm) var(--space-md);
}

.audience-card h3 {
  font-size: 16px;
  font-weight: 600;
  font-family: var(--font-body);
  margin-bottom: 6px;
}

.audience-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* 发帖流程步骤 */
.flow-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  counter-reset: flow-step;
}

.flow-step {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-sm) var(--space-md);
  counter-increment: flow-step;
  position: relative;
}

.step-number {
  display: block;
  font-family: var(--font-heading);
  font-size: 24px;
  font-weight: 700;
  color: var(--color-accent);
  line-height: 1;
  margin-bottom: 8px;
}

.flow-step .step-number::after {
  content: counter(flow-step);
}

.step-content h3 {
  font-size: 16px;
  font-weight: 600;
  font-family: var(--font-body);
  margin-bottom: 6px;
}

.step-content p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* 准备材料清单 */
.checklist {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.check-item {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-sm) var(--space-md);
}

.check-item h3 {
  font-size: 15px;
  font-weight: 600;
  font-family: var(--font-body);
  margin-bottom: 6px;
}

.check-item p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* 发布后说明 */
.after-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.after-item {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-sm) var(--space-md);
}

.after-item h3 {
  font-size: 15px;
  font-weight: 600;
  font-family: var(--font-body);
  margin-bottom: 6px;
}

.after-item p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* 反馈方式 */
.feedback-links {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.feedback-link {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-sm) var(--space-md);
  display: block;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.feedback-link:hover {
  border-color: var(--color-accent);
  box-shadow: 0 2px 12px rgba(38, 34, 29, 0.06);
}

.feedback-link-title {
  display: block;
  font-size: 16px;
  font-weight: 600;
  font-family: var(--font-body);
  margin-bottom: 4px;
}

.feedback-link-desc {
  display: block;
  font-size: 14px;
  color: var(--color-text-secondary);
}

/* ---------- 社区规则页 ---------- */

.rules-summary {
  max-width: 780px;
  margin-bottom: var(--space-lg);
}

.rules-summary > h2 {
  font-size: 20px;
  margin-bottom: var(--space-sm);
}

.summary-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.summary-card {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-left: 3px solid var(--color-accent);
  border-radius: var(--radius);
  padding: var(--space-sm) var(--space-md);
}

.summary-card h3 {
  font-size: 16px;
  font-weight: 600;
  font-family: var(--font-body);
  margin-bottom: 6px;
}

.summary-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* 详细条款 */
.rules-detailed {
  max-width: 780px;
  margin-bottom: var(--space-lg);
}

.rules-detailed > h2 {
  font-size: 20px;
  margin-bottom: var(--space-sm);
}

.rule-group {
  margin-bottom: var(--space-md);
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-md);
}

.rule-group h3 {
  font-size: 17px;
  font-weight: 600;
  font-family: var(--font-body);
  margin-bottom: 10px;
}

.rule-group .rule-list li {
  padding: 5px 0;
  font-size: 14px;
  line-height: 1.7;
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

.rule-group .rule-list li::before {
  content: "";
  flex-shrink: 0;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background-color: var(--color-border);
  margin-top: 11px;
}

/* 违规处理 */
.rule-enforcement {
  max-width: 780px;
  margin-bottom: var(--space-lg);
}

.rule-enforcement > h2 {
  font-size: 20px;
  margin-bottom: var(--space-sm);
}

.enforcement-steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.step-item {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-sm) var(--space-md);
}

.step-item h3 {
  font-size: 16px;
  font-weight: 600;
  font-family: var(--font-body);
  margin-bottom: 6px;
}

.step-item p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* 帮助入口 */
.help-entry {
  max-width: 780px;
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-md);
}

.help-entry h2 {
  font-size: 18px;
  margin-bottom: 6px;
  font-family: var(--font-body);
}

.help-entry > p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-sm);
}

.entry-links {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.entry-links a {
  display: inline-block;
  background-color: var(--color-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: 8px 18px;
  font-size: 14px;
  font-weight: 500;
  transition: border-color var(--transition-fast);
}

.entry-links a:hover {
  border-color: var(--color-accent);
}

/* ---------- 版本记录页 ---------- */

.version-current {
  max-width: var(--content-max);
  margin-bottom: var(--space-lg);
}

.version-current > h2 {
  font-size: 20px;
  margin-bottom: var(--space-sm);
}

.version-current-layout {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 24px;
  align-items: start;
}

.version-figure {
  border-radius: var(--radius);
  overflow: hidden;
  background-color: var(--color-border-light);
}

.version-figure img {
  width: 100%;
  height: 200px;
  object-fit: cover;
}

.version-current-text p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 10px;
}

.version-timeline {
  max-width: var(--content-max);
  margin-bottom: var(--space-lg);
}

.version-timeline > h2 {
  font-size: 20px;
  margin-bottom: 6px;
}

.timeline-lead {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-sm);
}

.timeline-list {
  position: relative;
  padding-left: 24px;
}

.timeline-list::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 4px;
  bottom: 4px;
  width: 1px;
  background-color: var(--color-border);
}

.timeline-item {
  position: relative;
  margin-bottom: var(--space-md);
}

.timeline-marker {
  position: absolute;
  left: -24px;
  top: 8px;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  background-color: var(--color-accent);
  border: 3px solid var(--color-bg);
  box-shadow: 0 0 0 1px var(--color-accent);
}

.timeline-content {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-sm) var(--space-md);
}

.timeline-content h3 {
  font-size: 16px;
  font-weight: 600;
  font-family: var(--font-body);
  margin-bottom: 4px;
}

.timeline-content p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

.archive-note {
  background-color: var(--color-bg);
  border: 1px dashed var(--color-border);
  border-radius: var(--radius);
  padding: var(--space-sm) var(--space-md);
  margin-top: var(--space-md);
}

.archive-note h3 {
  font-size: 15px;
  font-weight: 600;
  font-family: var(--font-body);
  margin-bottom: 4px;
}

.archive-note p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* 相关入口 */
.version-related {
  max-width: var(--content-max);
  margin-bottom: var(--space-lg);
}

.version-related h2 {
  font-size: 20px;
  margin-bottom: 6px;
}

.version-related > p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-sm);
}

.version-related .related-links li {
  margin-bottom: 8px;
}

.version-related .related-links a {
  font-size: 15px;
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

/* 页内相关链接导航 */
.related-links-nav {
  max-width: var(--content-max);
  border-top: 1px solid var(--color-border-light);
  padding-top: var(--space-sm);
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.related-links-label {
  font-size: 14px;
  color: var(--color-text-secondary);
}

.related-links-item {
  font-size: 14px;
  font-weight: 500;
}

/* ---------- 常见问题页 ---------- */

.faq-group {
  max-width: var(--content-max);
  margin-bottom: var(--space-md);
}

.faq-group-title {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: var(--space-sm);
  padding-bottom: 8px;
  border-bottom: 1px solid var(--color-border-light);
}

.faq-item {
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  margin-bottom: 10px;
}

.faq-item summary {
  padding: var(--space-sm) var(--space-md);
  font-size: 15px;
  font-weight: 500;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  transition: color var(--transition-fast);
}

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

.faq-item summary::after {
  content: "+";
  font-size: 20px;
  color: var(--color-accent);
  flex-shrink: 0;
  font-weight: 400;
  transition: transform var(--transition-fast);
}

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

.faq-item summary:hover {
  color: var(--color-accent);
}

.faq-item p {
  padding: 0 var(--space-md) var(--space-sm);
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

.faq-item p a {
  font-weight: 500;
}

/* 其他帮助入口 */
.help-entry-title {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 6px;
}

.help-entry > p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-sm);
}

.help-entry-list {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.help-entry-list li a {
  display: inline-block;
  background-color: var(--color-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: 8px 18px;
  font-size: 14px;
  font-weight: 500;
  transition: border-color var(--transition-fast);
}

.help-entry-list li a:hover {
  border-color: var(--color-accent);
}

/* ---------- 404 页面 ---------- */

.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-xl) var(--container-padding);
}

.error-panel {
  text-align: center;
  max-width: 520px;
  background-color: var(--color-card);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: var(--space-lg) var(--space-md);
}

.error-code {
  font-family: var(--font-heading);
  font-size: 72px;
  font-weight: 700;
  color: var(--color-accent);
  line-height: 1;
  margin-bottom: var(--space-sm);
}

.error-panel h1 {
  font-size: 24px;
  margin-bottom: 10px;
}

.error-desc {
  font-size: 15px;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-md);
}

.error-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: var(--space-sm);
}

.error-actions a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 24px;
  border-radius: var(--radius);
  font-size: 15px;
  font-weight: 500;
  min-height: 44px;
}

.btn-home {
  background-color: var(--color-accent);
  color: #FFFFFF;
}

.btn-home:hover {
  background-color: #8F422B;
  color: #FFFFFF;
}

.btn-board {
  background-color: var(--color-bg);
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

.btn-board:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.error-help {
  font-size: 13px;
  color: var(--color-text-secondary);
}

.error-help a {
  font-weight: 500;
}

/* ==========================================================
   5. Responsive — 响应式断点
   ========================================================== */

/* ---------- 桌面中等（≤1024px） ---------- */

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

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

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

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

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

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

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

/* ---------- 平板及以下（≤960px） ---------- */

@media (max-width: 960px) {
  .header-inner {
    min-height: 64px;
  }

  .nav-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
  }

  .nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  .nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2) {
    opacity: 0;
  }

  .nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    padding: 0 var(--container-padding);
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-normal);
  }

  .site-nav.is-open {
    max-height: none;
    padding-top: 8px;
    padding-bottom: 16px;
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    width: 100%;
  }

  .nav-list li a {
    display: block;
    padding: 12px 8px;
    font-size: 16px;
    border-bottom: 1px solid var(--color-border-light);
    border-radius: 0;
  }

  .btn-participate {
    margin-top: 12px;
    justify-content: center;
    width: 100%;
    padding: 12px 18px;
  }

  /* 首页首屏改为上下堆叠 */
  .layout-split {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .hero-aside {
    margin-top: 0;
  }

  /* 内页侧栏布局改为上下堆叠 */
  .layout-shell.page-layout {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .sidebar-column {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
  }

  .sidebar-column section {
    margin-bottom: 0;
  }

  /* 页脚改为两列 */
  .footer-inner {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }
}

/* ---------- 手机（≤640px） ---------- */

@media (max-width: 640px) {
  :root {
    --container-padding: 16px;
    --space-lg: 36px;
    --space-xl: 48px;
  }

  .brand-name {
    font-size: 20px;
  }

  .brand-slogan {
    font-size: 12px;
  }

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

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

  .hero-lead {
    font-size: 15px;
  }

  .hero-figure img {
    height: 200px;
  }

  .page-header-figure img,
  .page-header-media img {
    height: 180px;
  }

  .board-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .board-card img {
    height: 160px;
  }

  .topic-item {
    padding: 12px 16px;
  }

  .path-steps {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .forum-group-list {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .forum-row {
    padding: 12px 16px;
  }

  .sidebar-column {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .sidebar-column section {
    margin-bottom: 16px;
  }

  .audience-grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .flow-steps {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .checklist {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .after-grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .feedback-links {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .summary-grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .enforcement-steps {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .version-current-layout {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .version-figure img {
    height: 160px;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .footer-bottom p {
    font-size: 12px;
  }

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

  .error-panel {
    padding: var(--space-md) var(--space-sm);
  }

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

  .error-actions a {
    width: 100%;
  }

  .topic-tags {
    overflow-x: auto;
    flex-wrap: nowrap;
    padding-bottom: 4px;
    -webkit-overflow-scrolling: touch;
  }

  .tag {
    flex-shrink: 0;
  }

  .breadcrumb {
    font-size: 13px;
    margin-bottom: var(--space-sm);
  }

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

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

  .entry-links a {
    text-align: center;
  }

  .help-entry-list {
    flex-direction: column;
    gap: 8px;
  }

  .help-entry-list li a {
    text-align: center;
    width: 100%;
  }
}

/* ---------- 极小屏（≤360px） ---------- */

@media (max-width: 360px) {
  .header-inner {
    gap: 12px;
  }

  .brand-slogan {
    display: none;
  }

  .btn-participate {
    padding: 8px 14px;
    font-size: 14px;
  }
}