/* ============================================================
   51禁漫 - 五金从业者交流社区 全站样式
   版本: 1.0
   说明: 本文件为全站唯一样式表，按 base / layout / components /
         pages / responsive 分组。所有路径均为站点根绝对路径。
   ============================================================ */

/* ============================================================
   1. Base - 基础重置与全局变量
   ============================================================ */
:root {
  --color-primary: #1a3a5f;
  --color-primary-dark: #142e4b;
  --color-primary-light: #2a4f7a;
  --color-accent: #e67e22;
  --color-accent-dark: #c96a15;
  --color-bg: #f4f6f8;
  --color-card: #ffffff;
  --color-text: #333333;
  --color-text-secondary: #666666;
  --color-text-light: #999999;
  --color-border: #e3e7eb;
  --color-header-bg: #142e4b;
  --color-footer-bg: #1a2a3a;
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 2px 8px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 4px 16px rgba(0, 0, 0, 0.1);
  --container-width: 1200px;
  --header-height: 64px;
  --header-height-scrolled: 48px;
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial,
    sans-serif;
  --transition-speed: 0.2s;
}

*,
*::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: var(--font-family);
  font-size: 16px;
  line-height: 1.7;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-speed) ease;
}

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

ul,
ol {
  list-style: none;
}

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

/* 通用容器 */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 20px;
}

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

/* 站点主体 */
.site-body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  background-color: var(--color-bg);
}

/* 页头 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--color-header-bg);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
  transition: box-shadow var(--transition-speed) ease;
}

.header-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 20px;
  height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  transition: height var(--transition-speed) ease;
}

.site-header.is-scrolled .header-inner {
  height: var(--header-height-scrolled);
}

/* 品牌区 */
.brand-link {
  display: flex;
  align-items: baseline;
  gap: 10px;
  flex-shrink: 0;
}

.brand-name {
  font-size: 24px;
  font-weight: 700;
  color: #ffffff;
  letter-spacing: 0.5px;
  line-height: 1.2;
}

.brand-slogan {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.7);
  line-height: 1.4;
  white-space: nowrap;
}

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

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

.nav-item {
  position: relative;
}

.nav-item a {
  display: block;
  padding: 8px 16px;
  font-size: 15px;
  color: rgba(255, 255, 255, 0.85);
  border-radius: var(--radius-sm);
  transition: color var(--transition-speed) ease,
    background-color var(--transition-speed) ease;
}

.nav-item a:hover {
  color: #ffffff;
  background-color: rgba(255, 255, 255, 0.1);
}

.nav-item.is-current a,
.nav-item a.is-current {
  color: #ffffff;
  font-weight: 600;
  background-color: rgba(255, 255, 255, 0.12);
}

/* 移动端汉堡按钮 */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 10px;
  border-radius: var(--radius-sm);
}

.nav-toggle-bar {
  display: block;
  width: 24px;
  height: 2px;
  background-color: #ffffff;
  border-radius: 2px;
  transition: transform var(--transition-speed) ease,
    opacity var(--transition-speed) ease;
}

/* 页脚 */
.site-footer {
  background-color: var(--color-footer-bg);
  color: rgba(255, 255, 255, 0.8);
  margin-top: auto;
}

.footer-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 48px 20px 32px;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 48px;
}

.footer-title {
  font-size: 16px;
  font-weight: 600;
  color: #ffffff;
  margin-bottom: 16px;
  line-height: 1.4;
}

.footer-desc {
  font-size: 14px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.7);
}

.footer-links li {
  margin-bottom: 10px;
}

.footer-links a {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.7);
  transition: color var(--transition-speed) ease;
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: 16px 20px;
  text-align: center;
}

.footer-bottom p {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.5);
}

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

.inner-main {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 32px 20px 64px;
  width: 100%;
}

/* 面包屑 */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 24px;
  line-height: 1.6;
  flex-wrap: wrap;
}

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

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

.breadcrumb-sep {
  color: var(--color-text-light);
  user-select: none;
}

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

/* 页面标题区 */
.page-header {
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--color-border);
}

.page-title {
  font-size: 32px;
  font-weight: 700;
  color: var(--color-text);
  line-height: 1.3;
  margin-bottom: 12px;
}

.page-description {
  font-size: 16px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  max-width: 760px;
}

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

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 28px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-md);
  line-height: 1.5;
  transition: background-color var(--transition-speed) ease,
    color var(--transition-speed) ease,
    box-shadow var(--transition-speed) ease,
    border-color var(--transition-speed) ease;
  min-height: 44px;
}

.btn-primary {
  background-color: var(--color-primary);
  color: #ffffff;
  border: 1px solid var(--color-primary);
}

.btn-primary:hover {
  background-color: var(--color-primary-dark);
  color: #ffffff;
  box-shadow: var(--shadow-md);
}

.btn-outline {
  background-color: transparent;
  color: var(--color-primary);
  border: 1px solid var(--color-primary);
}

.btn-outline:hover {
  background-color: var(--color-primary);
  color: #ffffff;
  box-shadow: var(--shadow-md);
}

/* 区块标题 */
.section-head {
  margin-bottom: 24px;
}

.section-title {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-text);
  line-height: 1.4;
  margin-bottom: 8px;
}

.section-desc {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

/* 内容图片容器 */
.content-media {
  border-radius: var(--radius-lg);
  overflow: hidden;
  background-color: var(--color-border);
}

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

.content-media figcaption {
  padding: 10px 16px;
  font-size: 13px;
  color: var(--color-text-secondary);
  background-color: var(--color-card);
  line-height: 1.5;
}

/* 标签 */
.tag-item {
  display: inline-flex;
  align-items: center;
  padding: 8px 18px;
  font-size: 14px;
  color: var(--color-primary);
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  line-height: 1.5;
  transition: background-color var(--transition-speed) ease,
    color var(--transition-speed) ease,
    border-color var(--transition-speed) ease,
    box-shadow var(--transition-speed) ease;
}

.tag-item:hover {
  background-color: var(--color-primary);
  color: #ffffff;
  border-color: var(--color-primary);
  box-shadow: var(--shadow-sm);
}

/* 卡片通用 */
.category-card,
.experience-card,
.qa-card {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: box-shadow var(--transition-speed) ease,
    transform var(--transition-speed) ease;
}

.category-card:hover,
.experience-card:hover,
.qa-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

/* ============================================================
   4. Pages - 页面专属样式
   ============================================================ */

/* ---------- 首页 ---------- */
.home-main {
  width: 100%;
}

/* Hero 区域 */
.hero-section {
  background-color: var(--color-primary);
  color: #ffffff;
  padding: 56px 20px 64px;
}

.hero-content {
  max-width: var(--container-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 48px;
  align-items: center;
}

.hero-title {
  font-size: 36px;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 16px;
  color: #ffffff;
}

.hero-desc {
  font-size: 17px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: 24px;
  max-width: 560px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-actions .btn-primary {
  background-color: var(--color-accent);
  border-color: var(--color-accent);
  color: #ffffff;
}

.hero-actions .btn-primary:hover {
  background-color: var(--color-accent-dark);
  border-color: var(--color-accent-dark);
}

.hero-actions .btn-outline {
  border-color: rgba(255, 255, 255, 0.7);
  color: #ffffff;
}

.hero-actions .btn-outline:hover {
  background-color: rgba(255, 255, 255, 0.1);
  border-color: #ffffff;
}

.hero-figure {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

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

/* 首页主内容图片 */
.content-media-primary {
  margin-top: 40px;
  max-width: var(--container-width);
  margin-left: auto;
  margin-right: auto;
}

.content-media-primary img {
  height: 200px;
  object-fit: cover;
}

/* 版块导航区 */
.ban-kuai-nav-section {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 48px 20px 16px;
}

.ban-kuai-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* 热帖列表 */
.hot-threads-section {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 32px 20px 16px;
}

.thread-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.thread-item {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  transition: box-shadow var(--transition-speed) ease,
    border-color var(--transition-speed) ease;
}

.thread-item:hover {
  box-shadow: var(--shadow-sm);
  border-color: var(--color-primary-light);
}

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

.thread-cat {
  display: inline-block;
  padding: 2px 10px;
  font-size: 12px;
  color: var(--color-accent);
  background-color: rgba(230, 126, 34, 0.1);
  border-radius: 999px;
  line-height: 1.6;
}

.thread-time {
  font-size: 13px;
  color: var(--color-text-light);
}

.thread-title {
  font-size: 17px;
  font-weight: 600;
  line-height: 1.5;
  margin-bottom: 6px;
}

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

.thread-title a:hover {
  color: var(--color-primary);
}

.thread-excerpt {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* 最新求购 */
.latest-qiugou-section {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 32px 20px 16px;
}

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

.qiugou-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 24px;
  border-bottom: 1px solid var(--color-border);
  transition: background-color var(--transition-speed) ease;
}

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

.qiugou-item:hover {
  background-color: rgba(26, 58, 95, 0.04);
}

.qiugou-link {
  font-size: 15px;
  color: var(--color-text);
  line-height: 1.5;
  flex: 1;
}

.qiugou-link:hover {
  color: var(--color-primary);
}

.qiugou-time {
  font-size: 13px;
  color: var(--color-text-light);
  flex-shrink: 0;
}

/* 公告栏 */
.announcement-section {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 32px 20px 48px;
}

.announcement-box {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-accent);
  border-radius: var(--radius-md);
  padding: 24px 32px;
}

.announcement-title {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 8px;
  line-height: 1.4;
}

.announcement-text {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 8px;
}

.announcement-text a {
  color: var(--color-primary);
  font-weight: 500;
}

.announcement-date {
  font-size: 13px;
  color: var(--color-text-light);
}

/* ---------- 版块分类页 ---------- */
.page-ban-kuai .category-grid {
  margin-bottom: 40px;
}

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

.category-card {
  display: flex;
  flex-direction: column;
}

.category-card-media {
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background-color: var(--color-border);
}

.category-card-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s ease;
}

.category-card:hover .category-card-media img {
  transform: scale(1.03);
}

.category-card-body {
  padding: 20px 24px 24px;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.category-card-title {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-text);
  line-height: 1.4;
}

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

.category-description {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 32px;
}

.category-description-text {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 16px;
}

.category-description-text:last-child {
  margin-bottom: 0;
}

/* ---------- 版规说明页 ---------- */
.page-gui-ze .rules-layout {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 32px;
  align-items: start;
}

.rules-content {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 32px;
}

.rules-section {
  margin-bottom: 32px;
  padding-bottom: 32px;
  border-bottom: 1px solid var(--color-border);
}

.rules-section:last-child {
  margin-bottom: 0;
  padding-bottom: 0;
  border-bottom: none;
}

.rules-section h2 {
  font-size: 20px;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 12px;
  line-height: 1.4;
}

.rules-section > p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 16px;
}

.rules-list {
  list-style: none;
}

.rules-list li {
  position: relative;
  padding-left: 20px;
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 10px;
}

.rules-list li::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 10px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--color-accent);
}

.rules-list li strong {
  color: var(--color-text);
  font-weight: 600;
}

.content-media-inline {
  margin-top: 24px;
  border-radius: var(--radius-md);
}

.content-media-inline img {
  height: 220px;
  object-fit: cover;
}

.rules-aside {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.aside-card {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 24px;
}

.aside-card h3 {
  font-size: 16px;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 12px;
  line-height: 1.4;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-border);
}

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

/* ---------- 经验分享页 ---------- */
.page-jing-yan .page-container {
  width: 100%;
}

.layout-shell {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 32px;
  align-items: start;
}

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

.article-list-section {
  margin-bottom: 32px;
}

.article-list-section .section-title {
  margin-bottom: 20px;
}

.experience-card {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 0;
  margin-bottom: 20px;
}

.experience-card:last-child {
  margin-bottom: 0;
}

.card-figure {
  aspect-ratio: 16 / 10;
  overflow: hidden;
  background-color: var(--color-border);
}

.card-image {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s ease;
}

.experience-card:hover .card-image {
  transform: scale(1.03);
}

.card-body {
  padding: 20px 24px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.card-title {
  font-size: 18px;
  font-weight: 600;
  line-height: 1.5;
}

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

.card-title a:hover {
  color: var(--color-primary);
}

.card-excerpt {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.card-link {
  font-size: 14px;
  color: var(--color-primary);
  font-weight: 500;
  align-self: flex-start;
  margin-top: auto;
}

.card-link:hover {
  color: var(--color-accent);
}

/* 侧栏 */
.sidebar {
  min-width: 0;
}

.sidebar-card {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 24px;
}

.sidebar-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 16px;
  line-height: 1.4;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-border);
}

.topic-list {
  list-style: none;
}

.topic-list li {
  padding: 10px 0;
  border-bottom: 1px solid var(--color-border);
  font-size: 14px;
  line-height: 1.5;
}

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

.topic-list a {
  color: var(--color-text-secondary);
  transition: color var(--transition-speed) ease;
  display: block;
}

.topic-list a:hover {
  color: var(--color-primary);
}

/* ---------- 安装问答页 ---------- */
.faq-module {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 32px;
  margin-bottom: 40px;
}

.faq-module h2 {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 24px;
  line-height: 1.4;
}

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq-item {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--color-card);
}

.faq-item summary {
  padding: 16px 24px;
  font-size: 16px;
  font-weight: 600;
  color: var(--color-text);
  cursor: pointer;
  line-height: 1.5;
  list-style: none;
  position: relative;
  padding-right: 48px;
  transition: background-color var(--transition-speed) ease;
}

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

.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 20px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 22px;
  font-weight: 400;
  color: var(--color-primary);
  transition: transform var(--transition-speed) ease;
}

.faq-item[open] summary {
  background-color: rgba(26, 58, 95, 0.04);
}

.faq-item[open] summary::after {
  transform: translateY(-50%) rotate(45deg);
}

.faq-item p {
  padding: 0 24px 20px;
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* 最新问答 */
.latest-qa {
  margin-bottom: 40px;
}

.latest-qa h2 {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 20px;
  line-height: 1.4;
}

.qa-media-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.qa-card {
  display: flex;
  flex-direction: column;
}

.qa-figure {
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background-color: var(--color-border);
}

.qa-figure img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s ease;
}

.qa-card:hover .qa-figure img {
  transform: scale(1.03);
}

.qa-figure figcaption {
  padding: 8px 16px;
  font-size: 13px;
  color: var(--color-text-secondary);
  background-color: var(--color-card);
  line-height: 1.5;
}

.qa-card h3 {
  font-size: 17px;
  font-weight: 600;
  color: var(--color-text);
  padding: 16px 20px 0;
  line-height: 1.5;
}

.qa-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  padding: 8px 20px 0;
  line-height: 1.7;
  flex: 1;
}

.qa-card a {
  font-size: 14px;
  color: var(--color-primary);
  font-weight: 500;
  padding: 12px 20px 20px;
}

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

/* 安装技巧 */
.install-tips {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 32px;
}

.install-tips h2 {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 20px;
  line-height: 1.4;
}

.steps-list {
  list-style: none;
  counter-reset: step;
  margin-bottom: 20px;
}

.steps-list li {
  counter-increment: step;
  position: relative;
  padding-left: 44px;
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 16px;
}

.steps-list li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background-color: var(--color-primary);
  color: #ffffff;
  font-size: 14px;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  line-height: 1;
}

.install-tips > p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

.install-tips > p a {
  color: var(--color-primary);
  font-weight: 500;
}

/* ---------- 404 页 ---------- */
.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 80px 20px;
  min-height: 60vh;
}

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

.error-code {
  font-size: 72px;
  font-weight: 700;
  color: var(--color-primary);
  line-height: 1.2;
  margin-bottom: 16px;
}

.error-title {
  font-size: 28px;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 16px;
  line-height: 1.4;
}

.error-desc {
  font-size: 16px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 32px;
}

.error-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 32px;
}

.error-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 28px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-md);
  min-height: 44px;
  background-color: var(--color-primary);
  color: #ffffff;
  border: 1px solid var(--color-primary);
  transition: background-color var(--transition-speed) ease,
    box-shadow var(--transition-speed) ease;
}

.error-btn:hover {
  background-color: var(--color-primary-dark);
  color: #ffffff;
  box-shadow: var(--shadow-md);
}

.error-btn-secondary {
  background-color: transparent;
  color: var(--color-primary);
  border-color: var(--color-primary);
}

.error-btn-secondary:hover {
  background-color: var(--color-primary);
  color: #ffffff;
}

.error-help {
  font-size: 14px;
  color: var(--color-text-secondary);
}

.error-help a {
  color: var(--color-primary);
  font-weight: 500;
}

/* ============================================================
   5. Responsive - 响应式适配
   ============================================================ */

/* 平板及以下 */
@media (max-width: 1024px) {
  .hero-content {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .hero-figure img {
    height: 240px;
  }

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

  .layout-shell {
    grid-template-columns: 1fr;
  }

  .sidebar {
    order: 2;
  }

  .rules-layout {
    grid-template-columns: 1fr;
  }

  .rules-aside {
    order: 2;
  }

  .experience-card {
    grid-template-columns: 220px 1fr;
  }
}

/* 手机端 */
@media (max-width: 768px) {
  /* 页头 */
  .header-inner {
    height: var(--header-height);
    padding: 0 16px;
  }

  .brand-slogan {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    width: 100%;
    background-color: var(--color-header-bg);
    z-index: 200;
    transform: translateX(100%);
    transition: transform 0.3s ease;
    align-items: flex-start;
    justify-content: flex-start;
    padding: 80px 24px 24px;
    overflow-y: auto;
  }

  .site-nav.is-open {
    transform: translateX(0);
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    width: 100%;
    gap: 4px;
  }

  .nav-item a {
    padding: 14px 16px;
    font-size: 17px;
    border-radius: var(--radius-sm);
  }

  .nav-item.is-current a,
  .nav-item a.is-current {
    background-color: rgba(255, 255, 255, 0.15);
  }

  /* 汉堡按钮动画 */
  .nav-toggle.is-open .nav-toggle-bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  .nav-toggle.is-open .nav-toggle-bar:nth-child(2) {
    opacity: 0;
  }

  .nav-toggle.is-open .nav-toggle-bar:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  /* 全局容器 */
  .inner-main {
    padding: 24px 16px 48px;
  }

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

  .page-description {
    font-size: 15px;
  }

  /* 首页 */
  .hero-section {
    padding: 40px 16px 48px;
  }

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

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

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

  .content-media-primary img {
    height: 160px;
  }

  .ban-kuai-nav-section,
  .hot-threads-section,
  .latest-qiugou-section,
  .announcement-section {
    padding-left: 16px;
    padding-right: 16px;
  }

  .thread-item {
    padding: 16px;
  }

  .thread-title {
    font-size: 16px;
  }

  .qiugou-item {
    padding: 12px 16px;
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
  }

  .announcement-box {
    padding: 20px;
  }

  /* 版块分类 */
  .category-grid-list {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .category-card-media {
    aspect-ratio: 16 / 8;
  }

  .category-description {
    padding: 20px;
  }

  /* 版规页 */
  .rules-content {
    padding: 20px;
  }

  .rules-section h2 {
    font-size: 18px;
  }

  .content-media-inline img {
    height: 180px;
  }

  /* 经验页 */
  .experience-card {
    grid-template-columns: 1fr;
  }

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

  .card-body {
    padding: 16px;
  }

  .sidebar-card {
    padding: 20px;
  }

  /* 安装问答 */
  .faq-module {
    padding: 20px;
  }

  .faq-item summary {
    padding: 14px 44px 14px 16px;
    font-size: 15px;
  }

  .faq-item p {
    padding: 0 16px 16px;
    font-size: 14px;
  }

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

  .install-tips {
    padding: 20px;
  }

  .steps-list li {
    padding-left: 40px;
  }

  /* 页脚 */
  .footer-inner {
    grid-template-columns: 1fr;
    gap: 32px;
    padding: 40px 16px 24px;
  }

  /* 404 */
  .error-main {
    padding: 60px 16px;
  }

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

  .error-title {
    font-size: 24px;
  }
}

/* 小屏手机 */
@media (max-width: 390px) {
  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .hero-actions .btn {
    width: 100%;
  }

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

  .error-btn {
    width: 100%;
  }
}

/* 滚动状态 - 由 JS 添加类 */
.site-header.is-scrolled {
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}