/* ============================================================
   BASE — 全站基础变量、重置与骨架
   ============================================================ */
:root {
  --bg: #f7f5f0;
  --ink: #233946;
  --primary: #0f7c85;
  --warm: #e4775c;
  --sand: #efe6d8;
  --line: #d9cfc0;
  --white: #ffffff;
  --ink-soft: #556a76;
  --ink-faint: #7a8b94;
  --shadow-soft: 0 4px 14px rgba(35, 57, 70, 0.06);
  --shadow-hover: 0 8px 24px rgba(35, 57, 70, 0.1);
  --radius-sm: 4px;
  --radius-md: 8px;
  --container: 1120px;
  --header-h: 72px;
  --font-stack: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-stack);
  font-size: 16px;
  font-weight: 400;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

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

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

a {
  color: var(--primary);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

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

h1,
h2,
h3,
h4,
h5,
h6,
p,
figure {
  margin: 0;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
  padding: 0;
}

/* ============================================================
   LAYOUT — 页头、页脚、主容器、面包屑、页面标题区
   ============================================================ */

/* 页头 */
.site-header {
  background: rgba(247, 245, 240, 0.96);
  border-bottom: 1px solid var(--line);
  position: relative;
  z-index: 20;
}

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

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

.brand-name {
  font-size: 22px;
  font-weight: 700;
  color: var(--ink);
  letter-spacing: 1px;
}

.brand-tag {
  font-size: 13px;
  color: var(--ink-faint);
}

/* 主导航 — 桌面平铺 */
.site-nav {
  display: block;
}

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

.nav-item {
  position: relative;
}

.nav-link {
  display: block;
  padding: 8px 16px;
  font-size: 15px;
  color: var(--ink-soft);
  border-bottom: 2px solid transparent;
  line-height: 1.6;
  min-height: 44px;
  display: flex;
  align-items: center;
}

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

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

/* 汉堡按钮 — 默认隐藏 */
.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  border-radius: var(--radius-sm);
}

.toggle-bar {
  width: 22px;
  height: 2px;
  background: var(--ink);
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.25s ease;
}

/* 主容器 */
.site-main {
  flex: 1;
  width: 100%;
}

.home-main {
  overflow: visible;
}

.inner-main {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px 64px;
  width: 100%;
}

/* 面包屑 */
.breadcrumb {
  padding: 20px 0 0;
  font-size: 14px;
  color: var(--ink-faint);
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px;
}

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

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

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

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

/* 页面标题区 */
.page-header {
  padding: 28px 0 32px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 36px;
}

.page-title {
  font-size: 38px;
  font-weight: 700;
  color: var(--ink);
  line-height: 1.3;
  margin-bottom: 10px;
}

.page-description {
  font-size: 16px;
  color: var(--ink-soft);
  max-width: 720px;
}

/* 通用 section 标题 */
.section-title {
  font-size: 26px;
  font-weight: 700;
  color: var(--ink);
  line-height: 1.4;
  margin-bottom: 12px;
}

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

/* 页脚 */
.site-footer {
  background: var(--ink);
  color: #c9d2d6;
  margin-top: auto;
}

.footer-shell {
  max-width: var(--container);
  margin: 0 auto;
  padding: 48px 24px 24px;
  display: grid;
  grid-template-columns: 2fr repeat(4, 1fr);
  gap: 32px;
}

.footer-brand-name {
  font-size: 20px;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 8px;
}

.footer-brand-desc {
  font-size: 14px;
  color: #93a5ae;
  line-height: 1.7;
}

.footer-group-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--white);
  margin-bottom: 12px;
}

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

.footer-link {
  font-size: 14px;
  color: #a3b4bc;
  min-height: 28px;
  display: inline-flex;
  align-items: center;
}

.footer-link:hover {
  color: var(--warm);
}

.footer-copyright {
  grid-column: 1 / -1;
  font-size: 13px;
  color: #7d929c;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 16px;
  margin-top: 16px;
}

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

/* 锚点跳转平滑定位 */
[data-anchor-target] {
  scroll-margin-top: calc(var(--header-h) + 20px);
}

/* 文字链接 */
.text-link {
  color: var(--primary);
  font-weight: 500;
  border-bottom: 1px solid rgba(15, 124, 133, 0.3);
  transition: border-color 0.2s ease, color 0.2s ease;
}

.text-link:hover {
  color: var(--warm);
  border-bottom-color: rgba(228, 119, 92, 0.3);
}

/* ============================================================
   INDEX 页面级组件
   ============================================================ */

/* 首屏横幅 */
.hero-banner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 56px 24px 48px;
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 48px;
  align-items: center;
}

.hero-copy {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.hero-eyebrow {
  font-size: 14px;
  font-weight: 600;
  color: var(--warm);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 12px;
}

.hero-title {
  font-size: 40px;
  font-weight: 700;
  color: var(--ink);
  line-height: 1.3;
  margin-bottom: 16px;
}

.hero-lead {
  font-size: 17px;
  color: var(--ink-soft);
  line-height: 1.7;
  margin-bottom: 24px;
  max-width: 520px;
}

.hero-cta-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 28px;
}

.cta-primary,
.cta-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 24px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
}

.cta-primary {
  background: var(--primary);
  color: var(--white);
}

.cta-primary:hover {
  background: #0a6971;
  color: var(--white);
}

.cta-secondary {
  border: 1px solid var(--line);
  color: var(--ink);
  background: transparent;
}

.cta-secondary:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.hero-keywords {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.hero-keywords li {
  font-size: 13px;
  color: var(--ink-faint);
  background: var(--sand);
  border-radius: 20px;
  padding: 4px 14px;
}

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

.hero-figure img {
  width: 100%;
  height: 320px;
  object-fit: cover;
}

/* 首页内容媒体图 */
.content-media-primary {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}

.content-media-primary img {
  width: 100%;
  height: 280px;
  object-fit: cover;
  border-radius: var(--radius-md);
}

.content-media-primary figcaption {
  font-size: 13px;
  color: var(--ink-faint);
  padding: 8px 4px 0;
}

/* 首页通用 section 容器 */
.topic-preview,
.section-quicklist,
.freshman-duo {
  max-width: var(--container);
  margin: 0 auto;
  padding: 56px 24px;
}

.topic-preview {
  padding-top: 24px;
}

.section-quicklist {
  padding-top: 24px;
}

.freshman-duo {
  padding-top: 24px;
}

.section-heading {
  margin-bottom: 28px;
}

.section-kicker {
  font-size: 13px;
  font-weight: 600;
  color: var(--warm);
  margin-bottom: 6px;
}

/* 话题预览卡列表 */
.topic-card-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.topic-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 24px;
  transition: box-shadow 0.25s ease, transform 0.25s ease, border-color 0.25s ease;
}

.topic-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
  border-color: rgba(15, 124, 133, 0.4);
}

.topic-card-body {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.topic-board-label {
  font-size: 13px;
  font-weight: 600;
  color: var(--primary);
  background: rgba(15, 124, 133, 0.08);
  display: inline-block;
  padding: 2px 10px;
  border-radius: 20px;
  align-self: flex-start;
}

.topic-card-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--ink);
  line-height: 1.5;
}

.topic-card-text {
  font-size: 14px;
  color: var(--ink-soft);
  line-height: 1.7;
  flex: 1;
}

.topic-card-link {
  font-size: 14px;
  font-weight: 600;
  color: var(--primary);
  display: inline-flex;
  align-items: center;
  margin-top: 8px;
  min-height: 32px;
}

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

/* 版块速览 */
.section-card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.section-card {
  background: var(--sand);
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  padding: 24px;
  transition: box-shadow 0.25s ease, transform 0.25s ease, border-color 0.25s ease, background 0.25s ease;
}

.section-card:hover {
  background: var(--white);
  border-color: rgba(15, 124, 133, 0.35);
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}

.section-card-name {
  font-size: 18px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 8px;
}

.section-card-desc {
  font-size: 14px;
  color: var(--ink-soft);
  line-height: 1.7;
  margin-bottom: 12px;
}

.section-card-link {
  font-size: 14px;
  font-weight: 600;
  color: var(--primary);
  min-height: 32px;
  display: inline-flex;
  align-items: center;
}

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

/* 新人双入口 */
.freshman-entry-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.freshman-entry-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 32px;
  transition: box-shadow 0.25s ease, transform 0.25s ease;
}

.freshman-entry-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}

.freshman-entry-card h3 {
  font-size: 20px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 8px;
}

.freshman-entry-card h3::before {
  content: "";
  display: block;
  width: 28px;
  height: 3px;
  background: var(--warm);
  border-radius: 2px;
  margin-bottom: 12px;
}

.freshman-entry-text {
  font-size: 15px;
  color: var(--ink-soft);
  line-height: 1.7;
  margin-bottom: 16px;
}

.freshman-entry-link {
  font-size: 15px;
  font-weight: 600;
  color: var(--primary);
  min-height: 32px;
  display: inline-flex;
  align-items: center;
}

.freshman-entry-link:hover {
  color: var(--warm);
}

/* 首页 related-links */
.related-links {
  max-width: var(--container);
  margin: 0 auto;
  padding: 8px 24px 56px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}

.related-links-label {
  font-size: 14px;
  color: var(--ink-faint);
  margin-right: 4px;
}

.related-links-item {
  font-size: 14px;
  color: var(--primary);
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 4px 14px;
  min-height: 32px;
  display: inline-flex;
  align-items: center;
}

.related-links-item:hover {
  border-color: var(--primary);
  color: var(--primary);
}

/* ============================================================
   SECTIONS 页面级组件（版块总览）
   ============================================================ */

/* 版块导览总述 */
.sections-intro {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 48px;
  align-items: center;
  margin-bottom: 48px;
}

.intro-copy p {
  font-size: 15px;
  color: var(--ink-soft);
  line-height: 1.8;
  margin-bottom: 12px;
}

.intro-copy p:last-child {
  margin-bottom: 0;
}

.intro-media img {
  width: 100%;
  height: 260px;
  object-fit: cover;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-soft);
}

/* 展签列表 */
.exhibit-heading {
  margin-bottom: 32px;
}

.exhibit-heading p {
  font-size: 15px;
  color: var(--ink-soft);
}

.exhibit-list {
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.exhibit-card {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 32px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: box-shadow 0.25s ease, border-color 0.25s ease;
  scroll-margin-top: calc(var(--header-h) + 20px);
}

.exhibit-card:hover {
  box-shadow: var(--shadow-hover);
}

.card-media {
  background: var(--sand);
}

.card-media img {
  width: 100%;
  height: 100%;
  min-height: 220px;
  object-fit: cover;
}

.card-body {
  padding: 28px 28px 28px 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.card-title {
  font-size: 24px;
  font-weight: 700;
  color: var(--ink);
}

.card-desc {
  font-size: 15px;
  color: var(--ink-soft);
  line-height: 1.7;
}

.card-scope {
  display: flex;
  flex-direction: column;
  gap: 6px;
  border-left: 3px solid var(--sand);
  padding-left: 12px;
  margin: 4px 0;
}

.scope-label {
  font-size: 13px;
  font-weight: 600;
  color: var(--primary);
}

.card-scope p:not(.scope-label) {
  font-size: 14px;
  color: var(--ink-soft);
  line-height: 1.6;
}

.card-link {
  font-size: 14px;
  font-weight: 600;
  color: var(--primary);
  align-self: flex-start;
  min-height: 32px;
  display: inline-flex;
  align-items: center;
}

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

/* 找不到版块兜底 */
.board-fallout {
  background: var(--sand);
  border-radius: var(--radius-md);
  padding: 36px;
  margin-top: 48px;
}

.fallout-content h2 {
  margin-bottom: 12px;
}

.fallout-content p {
  font-size: 15px;
  color: var(--ink-soft);
  margin-bottom: 8px;
}

.fallout-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 16px;
}

.btn-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 20px;
  border-radius: var(--radius-md);
  font-size: 15px;
  font-weight: 600;
  background: var(--primary);
  color: var(--white);
  transition: background 0.2s ease;
}

.btn-link:hover {
  background: #0a6971;
  color: var(--white);
}

/* ============================================================
   TOPICS 页面级组件（话题索引）
   ============================================================ */

.topic-taster {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 40px;
  align-items: center;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 32px;
  margin-bottom: 48px;
}

.topic-taster-media img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  border-radius: var(--radius-md);
}

.topic-taster-text p {
  font-size: 15px;
  color: var(--ink-soft);
  line-height: 1.8;
  margin-bottom: 10px;
}

.topic-taster-text p:last-child {
  margin-bottom: 0;
}

.topic-lines {
  margin-bottom: 48px;
}

.topic-lines > .section-title {
  margin-bottom: 24px;
}

.topic-item {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 24px;
  align-items: center;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 24px 28px;
  margin-bottom: 16px;
  transition: box-shadow 0.25s ease, border-color 0.25s ease;
  scroll-margin-top: calc(var(--header-h) + 20px);
}

.topic-item:hover {
  box-shadow: var(--shadow-hover);
  border-color: rgba(15, 124, 133, 0.3);
}

.topic-item-main {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.topic-board-tag {
  font-size: 13px;
  font-weight: 600;
  color: var(--warm);
  align-self: flex-start;
  background: rgba(228, 119, 92, 0.08);
  padding: 2px 10px;
  border-radius: 20px;
}

.topic-item-title {
  font-size: 19px;
  font-weight: 700;
  color: var(--ink);
  line-height: 1.5;
}

.topic-item-desc {
  font-size: 14px;
  color: var(--ink-soft);
  line-height: 1.7;
}

.topic-item-aside {
  display: flex;
  align-items: center;
}

.topic-item-link {
  font-size: 14px;
  font-weight: 600;
  color: var(--primary);
  white-space: nowrap;
  min-height: 36px;
  display: inline-flex;
  align-items: center;
}

.topic-item-link:hover {
  color: var(--warm);
}

/* 发言前提醒 */
.topic-reminder {
  background: var(--sand);
  border-radius: var(--radius-md);
  padding: 32px;
  margin-bottom: 48px;
}

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

.reminder-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 16px;
}

.reminder-item {
  font-size: 15px;
  color: var(--ink-soft);
  padding-left: 20px;
  position: relative;
  line-height: 1.7;
}

.reminder-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--primary);
}

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

.reminder-more a {
  font-weight: 600;
}

/* ============================================================
   GUIDE 页面级组件（新手指南）
   ============================================================ */

.guide-layout {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 48px;
  align-items: start;
}

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

.content-aside {
  position: sticky;
  top: calc(var(--header-h) + 24px);
}

/* 指南媒体块 */
.guide-media-block {
  margin-bottom: 40px;
}

.guide-figure {
  margin-top: 16px;
}

.guide-figure img {
  width: 100%;
  height: 280px;
  object-fit: cover;
  border-radius: var(--radius-md);
}

.guide-figure figcaption {
  font-size: 13px;
  color: var(--ink-faint);
  padding: 8px 4px 0;
}

/* 四步任务 */
.guide-steps-section {
  margin-bottom: 48px;
}

.guide-steps-section .section-lead {
  font-size: 15px;
  color: var(--ink-soft);
  margin-bottom: 24px;
}

.guide-step-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
  counter-reset: step-counter;
}

.guide-step-item {
  counter-increment: step-counter;
}

.step-card {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 20px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 24px;
  transition: box-shadow 0.25s ease, border-color 0.25s ease;
}

.step-card:hover {
  box-shadow: var(--shadow-soft);
  border-color: rgba(15, 124, 133, 0.3);
}

.step-number {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--primary);
  color: var(--white);
  font-size: 16px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

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

.step-content {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.step-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--ink);
}

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

.step-check {
  font-size: 13px;
  color: var(--primary);
  font-weight: 600;
  margin-top: 4px;
  display: inline-block;
}

/* 发言前检查清单 */
.guide-checklist-section {
  margin-bottom: 48px;
}

.guide-checklist-section .section-lead {
  font-size: 15px;
  color: var(--ink-soft);
  margin-bottom: 24px;
}

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

.checklist-item {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 16px;
  align-items: start;
}

.checklist-item::before {
  content: "";
  width: 18px;
  height: 18px;
  border: 2px solid var(--line);
  border-radius: var(--radius-sm);
  flex-shrink: 0;
  margin-top: 4px;
}

.checklist-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 2px;
}

.checklist-text {
  font-size: 14px;
  color: var(--ink-soft);
  line-height: 1.6;
}

/* 右侧辅助栏 */
.aside-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 24px;
  margin-bottom: 16px;
}

.aside-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 8px;
}

.aside-text {
  font-size: 14px;
  color: var(--ink-soft);
  line-height: 1.7;
  margin-bottom: 16px;
}

.aside-link-list {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.aside-link-item {
  display: flex;
  flex-direction: column;
  padding: 8px 0;
  border-bottom: 1px solid var(--line);
}

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

.aside-link {
  font-size: 15px;
  font-weight: 600;
  color: var(--primary);
  min-height: 32px;
  display: inline-flex;
  align-items: center;
}

.aside-link:hover {
  color: var(--warm);
}

.aside-link-desc {
  font-size: 13px;
  color: var(--ink-faint);
  line-height: 1.5;
}

.aside-note {
  background: var(--sand);
  border-radius: var(--radius-md);
  padding: 20px;
}

.aside-note-text {
  font-size: 14px;
  color: var(--ink-soft);
  line-height: 1.7;
}

/* ============================================================
   RULES 页面级组件（社区公约）
   ============================================================ */

.rule-summary {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 40px;
  align-items: center;
  margin-bottom: 48px;
}

.rule-summary-content p {
  font-size: 15px;
  color: var(--ink-soft);
  line-height: 1.8;
  margin-bottom: 12px;
}

.rule-summary-content p:last-child {
  margin-bottom: 0;
}

.rule-figure img {
  width: 100%;
  height: 240px;
  object-fit: cover;
  border-radius: var(--radius-md);
}

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

.rule-groups > .section-title {
  margin-bottom: 24px;
}

.rule-group {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 28px;
  margin-bottom: 20px;
  scroll-margin-top: calc(var(--header-h) + 20px);
}

.rule-group-head {
  border-bottom: 1px solid var(--line);
  padding-bottom: 12px;
  margin-bottom: 16px;
}

.rule-group-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 4px;
}

.rule-group-desc {
  font-size: 14px;
  color: var(--ink-soft);
  line-height: 1.6;
}

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

.rule-item {
  font-size: 15px;
  color: var(--ink-soft);
  line-height: 1.7;
  padding-left: 20px;
  position: relative;
}

.rule-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--warm);
}

.rule-feedback {
  background: var(--sand);
  border-radius: var(--radius-md);
  padding: 32px;
  margin-bottom: 48px;
}

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

.rule-feedback-content p {
  font-size: 15px;
  color: var(--ink-soft);
  line-height: 1.8;
  margin-bottom: 8px;
}

.rule-feedback-content p:last-child {
  margin-bottom: 0;
}

/* ============================================================
   HELP 页面级组件（帮助中心）
   ============================================================ */

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

.help-figure img {
  width: 100%;
  height: 260px;
  object-fit: cover;
  border-radius: var(--radius-md);
}

.help-intro-section {
  margin-bottom: 40px;
}

.help-intro-section .section-paragraph {
  font-size: 15px;
  color: var(--ink-soft);
  line-height: 1.8;
  margin-bottom: 10px;
}

.help-intro-section .section-paragraph:last-child {
  margin-bottom: 0;
}

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

.faq-section > .section-title {
  margin-bottom: 24px;
}

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

.faq-group-title {
  font-size: 19px;
  font-weight: 700;
  color: var(--ink);
  padding-bottom: 8px;
  border-bottom: 2px solid var(--sand);
  margin-bottom: 12px;
}

.faq-details {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
  overflow: hidden;
  transition: border-color 0.2s ease;
}

.faq-details[open] {
  border-color: rgba(15, 124, 133, 0.4);
}

.faq-summary {
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
  padding: 16px 20px;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 48px;
  transition: color 0.2s ease;
}

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

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

.faq-summary::after {
  content: "+";
  font-size: 20px;
  font-weight: 400;
  color: var(--primary);
  flex-shrink: 0;
  transition: transform 0.25s ease;
}

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

.faq-content {
  padding: 0 20px 20px;
  border-top: 1px solid var(--line);
  padding-top: 16px;
}

.faq-content p {
  font-size: 14px;
  color: var(--ink-soft);
  line-height: 1.8;
  margin-bottom: 8px;
}

.faq-content p:last-child {
  margin-bottom: 0;
}

/* 兜底指引 */
.fallback-section {
  background: var(--sand);
  border-radius: var(--radius-md);
  padding: 32px;
  margin-bottom: 48px;
}

.fallback-section .section-paragraph {
  font-size: 15px;
  color: var(--ink-soft);
  line-height: 1.8;
  margin-bottom: 10px;
}

.fallback-section .section-paragraph:last-child {
  margin-bottom: 0;
}

/* 下一步入口 */
.next-steps-section {
  margin-bottom: 48px;
}

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

.next-step-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  transition: box-shadow 0.25s ease, transform 0.25s ease;
}

.next-step-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}

.next-step-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
}

.next-step-text {
  font-size: 13px;
  color: var(--ink-soft);
  line-height: 1.6;
  flex: 1;
}

.next-step-card .text-link {
  font-size: 14px;
}

/* ============================================================
   404 页面
   ============================================================ */

.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 80px 24px;
  flex: 1;
}

.error-panel {
  text-align: center;
  max-width: 560px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 48px 40px;
}

.error-code {
  font-size: 72px;
  font-weight: 700;
  color: var(--primary);
  line-height: 1;
  margin-bottom: 16px;
}

.error-title {
  font-size: 24px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 12px;
}

.error-desc {
  font-size: 15px;
  color: var(--ink-soft);
  line-height: 1.7;
  margin-bottom: 24px;
}

.error-back {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 24px;
  background: var(--primary);
  color: var(--white);
  border-radius: var(--radius-md);
  font-size: 15px;
  font-weight: 600;
  transition: background 0.2s ease;
}

.error-back:hover {
  background: #0a6971;
  color: var(--white);
}

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

@media (max-width: 960px) {
  .footer-shell {
    grid-template-columns: repeat(4, 1fr);
  }

  .footer-brand {
    grid-column: 1 / -1;
    margin-bottom: 8px;
  }

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

  .topic-card:last-child {
    grid-column: 1 / -1;
    max-width: none;
  }

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

  .exhibit-card {
    grid-template-columns: 1fr;
  }

  .card-body {
    padding: 0 28px 28px;
  }

  .card-media img {
    height: 200px;
  }

  .guide-layout {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .content-aside {
    position: static;
  }

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

@media (max-width: 768px) {
  .header-shell {
    height: auto;
    min-height: var(--header-h);
    padding: 8px 16px;
    flex-wrap: wrap;
    gap: 8px;
  }

  .brand-tag {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }

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

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

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

  .site-nav {
    width: 100%;
    order: 3;
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px 0;
    border-top: 1px solid var(--line);
  }

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

  .nav-item {
    width: 100%;
  }

  .nav-link {
    padding: 12px 8px;
    min-height: 44px;
    font-size: 16px;
    border-bottom: none;
    border-left: 3px solid transparent;
    justify-content: flex-start;
    display: flex;
    align-items: center;
  }

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

  .inner-main {
    padding: 0 16px 48px;
  }

  .breadcrumb {
    padding-top: 16px;
  }

  .page-header {
    padding: 20px 0 24px;
    margin-bottom: 28px;
  }

  .page-title {
    font-size: 30px;
  }

  .hero-banner {
    grid-template-columns: 1fr;
    gap: 24px;
    padding: 40px 16px 32px;
  }

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

  .hero-figure img {
    height: 220px;
  }

  .content-media-primary {
    padding: 0 16px;
  }

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

  .topic-preview,
  .section-quicklist,
  .freshman-duo {
    padding: 40px 16px;
  }

  .topic-preview {
    padding-top: 16px;
  }

  .section-quicklist {
    padding-top: 16px;
  }

  .freshman-duo {
    padding-top: 16px;
  }

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

  .topic-card:last-child {
    grid-column: auto;
  }

  .section-card-grid {
    grid-template-columns: 1fr;
  }

  .freshman-entry-grid {
    grid-template-columns: 1fr;
  }

  .related-links {
    padding: 0 16px 40px;
  }

  .sections-intro {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .intro-media img {
    height: 200px;
  }

  .exhibit-card {
    grid-template-columns: 1fr;
  }

  .card-media img {
    height: 180px;
  }

  .card-body {
    padding: 0 20px 24px;
  }

  .board-fallout {
    padding: 24px;
  }

  .topic-taster {
    grid-template-columns: 1fr;
    gap: 20px;
    padding: 20px;
  }

  .topic-taster-media img {
    height: 180px;
  }

  .topic-item {
    grid-template-columns: 1fr;
    gap: 12px;
    padding: 20px;
  }

  .topic-item-aside {
    justify-content: flex-start;
  }

  .topic-reminder {
    padding: 24px;
  }

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

  .step-card {
    grid-template-columns: 1fr;
    gap: 12px;
    padding: 20px;
  }

  .step-number {
    width: 36px;
    height: 36px;
  }

  .checklist-item {
    grid-template-columns: 1fr;
    gap: 8px;
    padding: 16px 20px;
  }

  .rule-summary {
    grid-template-columns: 1fr;
    gap: 24px;
  }

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

  .rule-group {
    padding: 20px;
  }

  .rule-feedback {
    padding: 24px;
  }

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

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

  .faq-content {
    padding: 0 16px 16px;
    padding-top: 14px;
  }

  .fallback-section {
    padding: 24px;
  }

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

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

  .error-panel {
    padding: 32px 24px;
  }

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

  .footer-shell {
    grid-template-columns: 1fr 1fr;
    padding: 40px 16px 24px;
    gap: 24px;
  }

  .footer-brand {
    grid-column: 1 / -1;
  }

  .footer-copyright {
    grid-column: 1 / -1;
  }
}

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

  .cta-primary,
  .cta-secondary {
    width: 100%;
  }

  .footer-shell {
    grid-template-columns: 1fr;
    gap: 20px;
  }
}