/* ==========================================================================
   91tangxingy.cn — 全站样式
   现代主义海报风：大胆色块、严格对齐、少量大字
   ========================================================================== */

/* ==========================================================================
   Base — 基础变量、重置、排版
   ========================================================================== */

:root {
  --color-dark: #1a1a2e;
  --color-accent: #e94560;
  --color-bg: #f5f5f5;
  --color-navy: #16213e;
  --color-white: #ffffff;
  --color-text: #2d2d3a;
  --color-text-light: #6b6b7b;
  --color-border: #e2e2ea;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;

  --container-width: 1200px;
  --container-pad: 24px;
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;

  --header-h: 64px;
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-5: 48px;
  --space-6: 64px;
}

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

html {
  font-size: 16px;
  line-height: 1.6;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

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

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

ul,
ol {
  list-style: none;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  color: var(--color-dark);
  line-height: 1.3;
  font-weight: 700;
}

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

/* ==========================================================================
   Layout — 全站骨架
   ========================================================================== */

.site-header {
  background-color: var(--color-dark);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}

.header-shell {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--container-pad);
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
}

.brand-link {
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.brand-name {
  font-size: 20px;
  font-weight: 800;
  color: var(--color-white);
  letter-spacing: 0.02em;
  white-space: nowrap;
}

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

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

.nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.nav-item {
  position: relative;
}

.nav-link {
  display: block;
  padding: 10px 14px;
  font-size: 15px;
  color: rgba(255, 255, 255, 0.85);
  border-radius: var(--radius-md);
  transition: background-color 0.2s ease, color 0.2s ease;
}

.nav-link:hover {
  color: var(--color-white);
  background-color: rgba(255, 255, 255, 0.08);
}

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

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 10px;
  border-radius: var(--radius-md);
}

.nav-toggle-bar {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--color-white);
  border-radius: 2px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.site-main {
  flex: 1 0 auto;
  width: 100%;
}

/* 页脚 */
.site-footer {
  background-color: var(--color-dark);
  color: rgba(255, 255, 255, 0.75);
  margin-top: var(--space-6);
}

.footer-shell {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: var(--space-5) var(--container-pad) var(--space-4);
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: var(--space-4);
}

.footer-brand-name {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-white);
  margin-bottom: var(--space-1);
}

.footer-tagline {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.6);
}

.footer-nav-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px var(--space-3);
}

.footer-nav-list a {
  color: rgba(255, 255, 255, 0.75);
  font-size: 14px;
}

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

.footer-meta {
  grid-column: 1 / -1;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding-top: var(--space-3);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: var(--space-2);
  font-size: 13px;
  color: rgba(255, 255, 255, 0.5);
}

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

/* 面包屑 */
.breadcrumb {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: var(--space-3) var(--container-pad) 0;
  font-size: 14px;
  color: var(--color-text-light);
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px;
}

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

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

.breadcrumb-sep {
  color: #b0b0c0;
}

.breadcrumb-current {
  color: var(--color-dark);
  font-weight: 500;
}

/* 页面标题区 */
.page-header {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: var(--space-4) var(--container-pad) var(--space-3);
}

.page-title {
  font-size: 32px;
  font-weight: 800;
  color: var(--color-dark);
  margin-bottom: var(--space-2);
}

.page-description {
  font-size: 16px;
  color: var(--color-text-light);
  max-width: 720px;
  line-height: 1.7;
}

/* 区块标题 */
.section-heading {
  margin-bottom: var(--space-4);
}

.section-title {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-dark);
  margin-bottom: var(--space-1);
}

.section-subtitle,
.section-desc {
  font-size: 15px;
  color: var(--color-text-light);
  max-width: 640px;
}

.section-more {
  margin-top: var(--space-3);
  text-align: right;
}

.section-more a {
  display: inline-block;
  font-size: 15px;
  font-weight: 500;
  color: var(--color-accent);
  padding: 8px 4px;
}

.section-more a:hover {
  color: var(--color-dark);
}

/* 按钮 */
.btn-primary,
.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 24px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: background-color 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

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

.btn-primary:hover {
  background-color: #d63851;
  color: var(--color-white);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(233, 69, 96, 0.3);
}

.btn-secondary {
  background-color: transparent;
  color: var(--color-white);
  border: 1.5px solid rgba(255, 255, 255, 0.6);
}

.btn-secondary:hover {
  border-color: var(--color-white);
  color: var(--color-white);
  background-color: rgba(255, 255, 255, 0.08);
}

/* 图片通用约束 */
figure {
  margin: 0;
}

img {
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ==========================================================================
   Home — 首页
   ========================================================================== */

.home-main {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--container-pad);
}

/* Hero */
.hero-section {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  align-items: center;
  gap: var(--space-5);
  background-color: var(--color-navy);
  border-radius: var(--radius-lg);
  margin-top: var(--space-3);
  padding: var(--space-5);
  overflow: hidden;
  position: relative;
}

.hero-copy {
  position: relative;
  z-index: 1;
}

.hero-title {
  font-size: 36px;
  font-weight: 800;
  color: var(--color-white);
  margin-bottom: var(--space-2);
  line-height: 1.25;
}

.hero-tagline {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-accent);
  margin-bottom: var(--space-2);
}

.hero-description {
  font-size: 15px;
  color: rgba(255, 255, 255, 0.8);
  margin-bottom: var(--space-4);
  max-width: 480px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.hero-figure {
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.3);
}

.hero-image {
  width: 100%;
  height: 320px;
  object-fit: cover;
  display: block;
}

/* 分类导航 */
.category-nav-section {
  padding: var(--space-6) 0 var(--space-3);
}

.category-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.tag-item {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 8px 20px;
  background-color: var(--color-white);
  border: 1.5px solid var(--color-border);
  border-radius: 999px;
  font-size: 15px;
  font-weight: 500;
  color: var(--color-dark);
  transition: border-color 0.2s ease, background-color 0.2s ease, color 0.2s ease;
}

.tag-item:hover {
  border-color: var(--color-accent);
  background-color: var(--color-accent);
  color: var(--color-white);
}

/* 最近更新 */
.latest-updates-section {
  padding: var(--space-5) 0;
}

.update-group {
  margin-bottom: var(--space-4);
}

.update-date-label {
  font-size: 16px;
  font-weight: 600;
  color: var(--color-navy);
  padding-bottom: var(--space-2);
  border-bottom: 2px solid var(--color-accent);
  margin-bottom: var(--space-3);
  display: inline-block;
}

.update-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-3);
}

.update-link {
  display: flex;
  flex-direction: column;
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--color-border);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.update-link:hover {
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
  transform: translateY(-2px);
}

.update-cover {
  width: 100%;
  height: 180px;
  object-fit: cover;
  display: block;
}

.update-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-dark);
  padding: var(--space-2) var(--space-2) 4px;
  line-height: 1.4;
}

.update-chapter {
  font-size: 13px;
  color: var(--color-accent);
  padding: 0 var(--space-2) var(--space-2);
}

/* 人气榜单预览 */
.ranking-preview-section {
  padding: var(--space-5) 0;
}

.ranking-preview-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.ranking-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  padding: var(--space-2);
  border: 1px solid var(--color-border);
  transition: box-shadow 0.2s ease;
}

.ranking-item:hover {
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.rank-badge {
  flex-shrink: 0;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--color-navy);
  color: var(--color-white);
  font-size: 15px;
  font-weight: 700;
  border-radius: var(--radius-sm);
}

.ranking-item:nth-child(1) .rank-badge {
  background-color: var(--color-accent);
}

.ranking-link {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  flex: 1;
  min-width: 0;
}

.ranking-cover {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-sm);
  object-fit: cover;
  flex-shrink: 0;
}

.ranking-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-dark);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.ranking-reason {
  font-size: 13px;
  color: var(--color-text-light);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* 指南入口 */
.guide-entry-section {
  padding: var(--space-5) 0;
}

.guide-cards {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-4);
}

.guide-card {
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  border: 1px solid var(--color-border);
  border-top: 3px solid var(--color-accent);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.guide-card:hover {
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.08);
  transform: translateY(-2px);
}

.guide-card-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-dark);
  margin-bottom: var(--space-1);
}

.guide-card-text {
  font-size: 14px;
  color: var(--color-text-light);
  margin-bottom: var(--space-3);
  line-height: 1.6;
}

.guide-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 15px;
  font-weight: 600;
  color: var(--color-accent);
}

.guide-link:hover {
  color: var(--color-dark);
}

/* 站点说明 */
.site-notice-section {
  padding: var(--space-4) 0 var(--space-5);
  border-top: 1px solid var(--color-border);
}

.notice-text {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.7;
  max-width: 760px;
}

/* ==========================================================================
   Inner Pages — 内页通用
   ========================================================================== */

.inner-main {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--container-pad);
}

/* ==========================================================================
   Categories — 题材分类页
   ========================================================================== */

.layout-shell {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: var(--space-4);
  align-items: start;
}

.sidebar-left .category-index {
  position: sticky;
  top: calc(var(--header-h) + var(--space-3));
}

.category-index {
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  padding: var(--space-3);
}

.aside-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-dark);
  padding-bottom: var(--space-2);
  border-bottom: 2px solid var(--color-accent);
  margin-bottom: var(--space-2);
}

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

.index-list li {
  border-bottom: 1px solid var(--color-border);
}

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

.index-list a {
  display: block;
  padding: 10px 4px;
  font-size: 15px;
  color: var(--color-text);
  transition: color 0.2s ease, padding-left 0.2s ease;
}

.index-list a:hover {
  color: var(--color-accent);
  padding-left: 8px;
}

.category-detail {
  display: flex;
  flex-direction: column;
  gap: var(--space-5);
}

.category-block {
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  padding: var(--space-4);
}

.block-title {
  font-size: 22px;
  font-weight: 700;
  color: var(--color-dark);
  margin-bottom: var(--space-1);
  padding-bottom: var(--space-1);
  border-bottom: 2px solid var(--color-accent);
  display: inline-block;
}

.block-desc {
  font-size: 15px;
  color: var(--color-text);
  margin-bottom: var(--space-3);
  line-height: 1.7;
}

.category-figure {
  border-radius: var(--radius-md);
  overflow: hidden;
  margin-bottom: var(--space-2);
}

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

.category-figure figcaption {
  font-size: 13px;
  color: var(--color-text-light);
  padding: var(--space-1) var(--space-2);
  background-color: var(--color-bg);
}

.block-example {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.6;
}

.category-guide-entry {
  margin-top: var(--space-5);
  background-color: var(--color-navy);
  border-radius: var(--radius-md);
  padding: var(--space-4);
}

.category-guide-entry .block-title {
  color: var(--color-white);
  border-bottom-color: var(--color-accent);
}

.category-guide-entry p {
  color: rgba(255, 255, 255, 0.85);
  font-size: 15px;
  line-height: 1.7;
}

.category-guide-entry a {
  color: var(--color-accent);
  font-weight: 500;
  margin-right: var(--space-3);
}

.category-guide-entry a:hover {
  color: var(--color-white);
}

/* ==========================================================================
   Guide — 阅读指南页
   ========================================================================== */

.guide-layout {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: var(--space-4);
  align-items: start;
  margin-bottom: var(--space-5);
}

.guide-steps {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.guide-steps > h2 {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-dark);
  padding-bottom: var(--space-2);
  border-bottom: 2px solid var(--color-accent);
  display: inline-block;
  align-self: flex-start;
}

.guide-step {
  display: flex;
  gap: var(--space-3);
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  padding: var(--space-4);
}

.step-number {
  flex-shrink: 0;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--color-accent);
  color: var(--color-white);
  font-size: 20px;
  font-weight: 700;
  border-radius: var(--radius-sm);
}

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

.step-content h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-dark);
  margin-bottom: var(--space-1);
}

.step-content p {
  font-size: 15px;
  color: var(--color-text);
  line-height: 1.7;
  margin-bottom: var(--space-2);
}

.step-content a {
  color: var(--color-accent);
  font-weight: 500;
}

.step-content a:hover {
  color: var(--color-dark);
}

.guide-figure {
  border-radius: var(--radius-md);
  overflow: hidden;
  margin-top: var(--space-2);
}

.guide-figure img {
  width: 100%;
  height: 180px;
  object-fit: cover;
}

.guide-figure figcaption {
  font-size: 13px;
  color: var(--color-text-light);
  padding: var(--space-1) var(--space-2);
  background-color: var(--color-bg);
}

.guide-aside {
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  padding: var(--space-3);
  position: sticky;
  top: calc(var(--header-h) + var(--space-3));
}

.guide-aside h2 {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-dark);
  padding-bottom: var(--space-2);
  border-bottom: 2px solid var(--color-accent);
  margin-bottom: var(--space-2);
}

.guide-tips-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.guide-tips-list li {
  font-size: 14px;
  color: var(--color-text);
  padding-left: var(--space-2);
  position: relative;
  line-height: 1.6;
}

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

/* FAQ */
.guide-faq {
  margin-bottom: var(--space-5);
}

.guide-faq > h2 {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-dark);
  margin-bottom: var(--space-3);
  padding-bottom: var(--space-2);
  border-bottom: 2px solid var(--color-accent);
  display: inline-block;
}

.faq-item {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-2);
  overflow: hidden;
}

.faq-item summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-3);
  font-size: 15px;
  font-weight: 600;
  color: var(--color-dark);
  cursor: pointer;
  list-style: none;
  transition: background-color 0.2s ease;
}

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

.faq-item summary::after {
  content: "+";
  font-size: 20px;
  color: var(--color-accent);
  flex-shrink: 0;
  margin-left: var(--space-2);
  transition: transform 0.2s ease;
}

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

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

.faq-item p {
  padding: 0 var(--space-3) var(--space-3);
  font-size: 15px;
  color: var(--color-text);
  line-height: 1.7;
}

/* ==========================================================================
   Latest — 最近更新页
   ========================================================================== */

.update-section {
  margin-bottom: var(--space-5);
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  padding: var(--space-4);
}

.update-section .section-title {
  font-size: 22px;
  font-weight: 700;
  color: var(--color-dark);
  padding-bottom: var(--space-1);
  border-bottom: 2px solid var(--color-accent);
  display: inline-block;
  margin-bottom: var(--space-1);
}

.update-section .section-desc {
  margin-bottom: var(--space-3);
}

.update-section .update-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-3);
}

.update-section .update-item {
  background-color: var(--color-bg);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--color-border);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.update-section .update-item:hover {
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
  transform: translateY(-2px);
}

.update-figure {
  overflow: hidden;
}

.update-figure .update-cover {
  width: 100%;
  height: 160px;
  object-fit: cover;
}

.update-info {
  padding: var(--space-2);
}

.update-title {
  font-size: 15px;
  font-weight: 600;
  line-height: 1.4;
  margin-bottom: 4px;
}

.update-title a {
  color: var(--color-dark);
}

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

.update-meta {
  font-size: 13px;
  color: var(--color-text-light);
  margin-bottom: var(--space-1);
}

.update-brief {
  font-size: 13px;
  color: var(--color-text-light);
  line-height: 1.5;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* 更新提示 */
.update-tips {
  background-color: var(--color-navy);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  margin-bottom: var(--space-5);
}

.update-tips .section-title {
  color: var(--color-white);
  font-size: 20px;
  margin-bottom: var(--space-2);
}

.update-tips p {
  color: rgba(255, 255, 255, 0.85);
  font-size: 15px;
  line-height: 1.7;
  margin-bottom: var(--space-2);
}

.update-tips a {
  color: var(--color-accent);
  font-weight: 500;
  margin-right: var(--space-3);
}

.update-tips a:hover {
  color: var(--color-white);
}

/* ==========================================================================
   Ranking — 人气榜单页
   ========================================================================== */

.page-layout {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: var(--space-4);
  align-items: start;
  margin-bottom: var(--space-5);
}

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

.ranking-section {
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  padding: var(--space-4);
  margin-bottom: var(--space-4);
}

.ranking-section .section-title {
  font-size: 22px;
  font-weight: 700;
  color: var(--color-dark);
  padding-bottom: var(--space-1);
  border-bottom: 2px solid var(--color-accent);
  display: inline-block;
  margin-bottom: var(--space-1);
}

.ranking-section .section-desc {
  margin-bottom: var(--space-3);
}

.ranking-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.ranking-list .ranking-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background-color: var(--color-bg);
}

.ranking-list .ranking-item:hover {
  border-color: var(--color-accent);
  background-color: var(--color-white);
}

.ranking-number {
  flex-shrink: 0;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--color-navy);
  color: var(--color-white);
  font-size: 14px;
  font-weight: 700;
  border-radius: var(--radius-sm);
}

.ranking-list .ranking-item:nth-child(1) .ranking-number {
  background-color: var(--color-accent);
}

.ranking-list .ranking-item:nth-child(2) .ranking-number {
  background-color: #d6455d;
}

.ranking-list .ranking-item:nth-child(3) .ranking-number {
  background-color: #c05060;
}

.ranking-cover {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-sm);
  object-fit: cover;
  flex-shrink: 0;
}

.ranking-info {
  flex: 1;
  min-width: 0;
}

.ranking-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-dark);
  margin-bottom: 2px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.ranking-reason {
  font-size: 13px;
  color: var(--color-text-light);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* 榜单说明 */
.ranking-note {
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  padding: var(--space-4);
}

.ranking-note .section-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-dark);
  margin-bottom: var(--space-2);
}

.ranking-note p {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.7;
  margin-bottom: var(--space-1);
}

/* 侧栏 */
.page-sidebar {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  position: sticky;
  top: calc(var(--header-h) + var(--space-3));
}

.sidebar-card {
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  padding: var(--space-3);
}

.sidebar-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--color-dark);
  padding-bottom: var(--space-2);
  border-bottom: 2px solid var(--color-accent);
  margin-bottom: var(--space-2);
}

.sidebar-links,
.sidebar-list {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.sidebar-links a,
.sidebar-list a {
  display: block;
  padding: 8px 4px;
  font-size: 14px;
  color: var(--color-text);
  border-bottom: 1px solid var(--color-border);
  transition: color 0.2s ease, padding-left 0.2s ease;
}

.sidebar-links a:hover,
.sidebar-list a:hover {
  color: var(--color-accent);
  padding-left: 8px;
}

.sidebar-links li:last-child a,
.sidebar-list li:last-child a {
  border-bottom: none;
}

/* ==========================================================================
   Tips — 追更技巧页
   ========================================================================== */

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

.article-figure {
  border-radius: var(--radius-md);
  overflow: hidden;
  margin-bottom: var(--space-4);
}

.article-figure img {
  width: 100%;
  height: 240px;
  object-fit: cover;
}

.article-figure figcaption {
  font-size: 13px;
  color: var(--color-text-light);
  padding: var(--space-1) var(--space-2);
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-top: none;
}

.content-section {
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  padding: var(--space-4);
  margin-bottom: var(--space-4);
}

.content-section .section-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--color-dark);
  padding-bottom: var(--space-1);
  border-bottom: 2px solid var(--color-accent);
  display: inline-block;
  margin-bottom: var(--space-2);
}

.content-section p {
  font-size: 15px;
  color: var(--color-text);
  line-height: 1.7;
  margin-bottom: var(--space-2);
}

.content-section a {
  color: var(--color-accent);
  font-weight: 500;
}

.content-section a:hover {
  color: var(--color-dark);
}

.content-list {
  margin: var(--space-2) 0;
  padding-left: var(--space-3);
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.content-list li {
  font-size: 15px;
  color: var(--color-text);
  line-height: 1.6;
  position: relative;
  padding-left: var(--space-2);
}

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

/* 相关链接 */
.related-links {
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  padding: var(--space-4);
}

.related-links .section-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-dark);
  margin-bottom: var(--space-2);
}

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

.related-list a {
  display: block;
  padding: 8px 4px;
  font-size: 15px;
  color: var(--color-text);
  border-bottom: 1px solid var(--color-border);
  transition: color 0.2s ease;
}

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

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

/* ==========================================================================
   Error — 404 页
   ========================================================================== */

.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-6) var(--container-pad);
  min-height: 60vh;
}

.error-panel {
  text-align: center;
  max-width: 520px;
  background-color: var(--color-white);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  padding: var(--space-5);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
}

.error-code {
  font-size: 72px;
  font-weight: 800;
  color: var(--color-accent);
  line-height: 1;
  margin-bottom: var(--space-2);
}

.error-title {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-dark);
  margin-bottom: var(--space-2);
}

.error-desc {
  font-size: 15px;
  color: var(--color-text-light);
  line-height: 1.7;
  margin-bottom: var(--space-4);
}

.error-actions {
  display: flex;
  justify-content: center;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.error-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 24px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-md);
  background-color: var(--color-accent);
  color: var(--color-white);
  transition: background-color 0.2s ease;
}

.error-btn:hover {
  background-color: #d63851;
  color: var(--color-white);
}

.error-btn-secondary {
  background-color: transparent;
  color: var(--color-navy);
  border: 1.5px solid var(--color-navy);
}

.error-btn-secondary:hover {
  background-color: var(--color-navy);
  color: var(--color-white);
}

/* ==========================================================================
   Responsive — 响应式
   ========================================================================== */

/* 平板及以下 */
@media (max-width: 992px) {
  .hero-section {
    grid-template-columns: 1fr;
    padding: var(--space-4);
    gap: var(--space-3);
  }

  .hero-figure {
    order: -1;
  }

  .hero-image {
    height: 220px;
  }

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

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

  .layout-shell {
    grid-template-columns: 200px 1fr;
    gap: var(--space-3);
  }

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

  .guide-aside {
    position: static;
  }

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

  .page-sidebar {
    position: static;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
  }
}

/* 手机 */
@media (max-width: 640px) {
  :root {
    --container-pad: 16px;
  }

  .header-shell {
    height: 56px;
  }

  .brand-name {
    font-size: 17px;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    top: 56px;
    left: 0;
    right: 0;
    background-color: var(--color-dark);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    padding: var(--space-2) var(--container-pad) var(--space-3);
    gap: 2px;
  }

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

  .nav-link {
    padding: 12px 8px;
    font-size: 16px;
    border-radius: var(--radius-sm);
  }

  .nav-item {
    width: 100%;
  }

  /* 首页 */
  .hero-section {
    padding: var(--space-3);
    margin-top: var(--space-2);
  }

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

  .hero-tagline {
    font-size: 16px;
  }

  .hero-description {
    font-size: 14px;
  }

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

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

  .hero-image {
    height: 180px;
  }

  .category-tags {
    gap: 8px;
  }

  .tag-item {
    padding: 6px 14px;
    font-size: 14px;
    min-height: 40px;
  }

  .update-list,
  .update-section .update-list {
    grid-template-columns: 1fr;
  }

  .update-cover {
    height: 200px;
  }

  .update-section .update-cover {
    height: 200px;
  }

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

  .ranking-link {
    flex-direction: column;
    align-items: flex-start;
  }

  .ranking-cover {
    width: 100%;
    height: 140px;
  }

  .ranking-title,
  .ranking-reason {
    white-space: normal;
  }

  /* 内页 */
  .page-title {
    font-size: 24px;
  }

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

  .breadcrumb {
    padding-top: var(--space-2);
    font-size: 13px;
  }

  /* 分类页 */
  .layout-shell {
    grid-template-columns: 1fr;
  }

  .category-index {
    position: static;
  }

  .index-list {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 4px;
  }

  .index-list li {
    border-bottom: none;
  }

  .index-list a {
    padding: 8px 12px;
    background-color: var(--color-bg);
    border-radius: 999px;
    font-size: 14px;
  }

  .index-list a:hover {
    padding-left: 12px;
  }

  .category-block {
    padding: var(--space-3);
  }

  .block-title {
    font-size: 20px;
  }

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

  .category-guide-entry {
    padding: var(--space-3);
  }

  .category-guide-entry a {
    display: block;
    margin: var(--space-1) 0;
  }

  /* 指南页 */
  .guide-step {
    flex-direction: column;
    padding: var(--space-3);
  }

  .step-number {
    width: 36px;
    height: 36px;
    font-size: 18px;
  }

  .guide-figure img {
    height: 150px;
  }

  .faq-item summary {
    padding: var(--space-2);
    font-size: 14px;
  }

  .faq-item p {
    padding: 0 var(--space-2) var(--space-2);
    font-size: 14px;
  }

  /* 更新页 */
  .update-section {
    padding: var(--space-3);
  }

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

  .update-tips {
    padding: var(--space-3);
  }

  .update-tips a {
    display: block;
    margin: var(--space-1) 0;
  }

  /* 榜单页 */
  .ranking-section {
    padding: var(--space-3);
  }

  .ranking-list .ranking-item {
    flex-wrap: wrap;
  }

  .ranking-cover {
    width: 48px;
    height: 48px;
  }

  .ranking-info {
    flex: 1;
    min-width: calc(100% - 90px);
  }

  .ranking-title,
  .ranking-reason {
    white-space: normal;
  }

  .page-sidebar {
    grid-template-columns: 1fr;
  }

  /* 技巧页 */
  .article-figure img {
    height: 180px;
  }

  .content-section {
    padding: var(--space-3);
  }

  .related-links {
    padding: var(--space-3);
  }

  /* 404 */
  .error-code {
    font-size: 56px;
  }

  .error-panel {
    padding: var(--space-4);
  }

  /* 页脚 */
  .footer-shell {
    grid-template-columns: 1fr;
    gap: var(--space-3);
    padding: var(--space-4) var(--container-pad) var(--space-3);
  }

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

  .footer-meta {
    flex-direction: column;
    gap: var(--space-1);
  }
}

/* 小屏手机 */
@media (max-width: 380px) {
  .hero-title {
    font-size: 22px;
  }

  .tag-item {
    padding: 6px 10px;
    font-size: 13px;
  }

  .update-cover,
  .update-section .update-cover {
    height: 160px;
  }
}