@import url('https://fonts.googleapis.com/css2?family=Nunito+Sans:wght@300;400;500;600;700&family=Varela+Round&display=swap');

/* ===== CSS 变量 ===== */
:root {
  --black: #000000;
  --white: #ffffff;
  --gray-100: #f5f5f5;
  --gray-200: #e8e8e8;
  --gray-400: #999999;
  --gray-600: #555555;
  --nav-width: 240px;
  --font-main: 'Nunito Sans', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-brand: 'Varela Round', 'Nunito Sans', sans-serif;
  --radius: 0;
  --border: 1px solid var(--black);
  --transition: 220ms ease;
}

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

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

body {
  font-family: var(--font-main);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--black);
  background: var(--white);
  overflow-x: hidden;
}

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

a {
  color: var(--black);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition);
}

a:hover, a:focus-visible {
  border-bottom-color: var(--black);
  outline: none;
}

a:focus-visible {
  outline: 2px solid var(--black);
  outline-offset: 2px;
}

menu, ul, ol {
  list-style: none;
}

/* ===== 布局骨架 ===== */
.site-wrap {
  display: flex;
  min-height: 100vh;
}

/* ===== 侧边导航 ===== */
.nav-details {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--nav-width);
  height: 100vh;
  background: var(--black);
  color: var(--white);
  z-index: 100;
  display: flex;
  flex-direction: column;
  border-right: 2px solid var(--black);
  overflow-y: auto;
}

.nav-toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.5rem 1.25rem;
  cursor: pointer;
  list-style: none;
  border-bottom: 1px solid rgba(255,255,255,0.15);
  min-height: 64px;
}

.nav-toggle::-webkit-details-marker { display: none; }
.nav-toggle::marker { display: none; }

.nav-brand {
  font-family: var(--font-brand);
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--white);
  line-height: 1.3;
  letter-spacing: 0.02em;
  word-break: break-all;
}

.nav-icon {
  font-size: 1.25rem;
  color: var(--white);
  flex-shrink: 0;
  margin-left: 0.5rem;
}

.nav-menu {
  display: flex;
  flex-direction: column;
  padding: 1rem 0;
  gap: 0.25rem;
}

.nav-menu li a {
  display: block;
  padding: 0.625rem 1.25rem;
  color: rgba(255,255,255,0.85);
  font-size: 0.8125rem;
  font-weight: 500;
  border-bottom: none;
  border-left: 3px solid transparent;
  transition: background var(--transition), border-left-color var(--transition), color var(--transition);
  min-height: 40px;
  line-height: 1.4;
  display: flex;
  align-items: center;
}

.nav-menu li a:hover,
.nav-menu li a:focus-visible {
  background: rgba(255,255,255,0.1);
  border-left-color: var(--white);
  color: var(--white);
  outline: none;
}

.nav-menu li a[aria-current="page"] {
  background: var(--white);
  color: var(--black);
  border-left-color: var(--white);
  font-weight: 700;
}

/* details 默认展开 */
.nav-details[open] .nav-menu { display: flex; }
.nav-details .nav-menu { display: flex; }

/* ===== 内容区偏移 ===== */
.content-shift {
  margin-left: var(--nav-width);
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
}

/* ===== 小眉题 ===== */
small.eyebrow {
  display: block;
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--gray-400);
  margin-bottom: 0.5rem;
}

/* ===== Hero (首页) ===== */
.hero-section {
  width: 100%;
  min-height: 70vh;
  background: var(--black);
  position: relative;
  overflow: hidden;
}

.hero-figure {
  width: 100%;
  min-height: 70vh;
  margin: 0;
  position: relative;
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: end;
}

.hero-bg-img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.35;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(0,0,0,0.7) 0%, rgba(0,0,0,0.3) 100%);
}

.hero-caption {
  position: relative;
  z-index: 2;
  padding: 4rem 3rem;
  text-align: right;
  grid-column: 2;
  grid-row: 1;
}

.hero-eyebrow {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  color: rgba(255,255,255,0.6);
  margin-bottom: 1rem;
  text-transform: uppercase;
}

.hero-caption h1 {
  font-family: var(--font-brand);
  font-size: clamp(1.5rem, 3vw, 2.75rem);
  font-weight: 700;
  color: var(--white);
  line-height: 1.2;
  margin-bottom: 1.25rem;
  word-break: break-all;
}

.hero-desc {
  font-size: 1rem;
  color: rgba(255,255,255,0.8);
  margin-bottom: 2rem;
  line-height: 1.7;
}

.hero-btn {
  display: inline-block;
  padding: 0.75rem 2rem;
  background: var(--white);
  color: var(--black);
  font-weight: 700;
  font-size: 0.875rem;
  letter-spacing: 0.05em;
  border: 2px solid var(--white);
  border-bottom: 2px solid var(--white);
  transition: background var(--transition), color var(--transition);
  min-height: 44px;
}

.hero-btn:hover, .hero-btn:focus-visible {
  background: transparent;
  color: var(--white);
  border-bottom-color: var(--white);
}

.hero-aside {
  position: relative;
  z-index: 2;
  grid-column: 1;
  grid-row: 1;
  padding: 4rem 3rem;
  align-self: end;
}

.hero-aside p {
  font-size: 0.8125rem;
  color: rgba(255,255,255,0.5);
  margin-bottom: 0.75rem;
  letter-spacing: 0.05em;
}

.hero-aside a {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.7);
  border-bottom: 1px solid rgba(255,255,255,0.3);
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0;
}

.hero-aside a:hover {
  color: var(--white);
  border-bottom-color: var(--white);
}

/* ===== 首页内容区 ===== */
.home-content-section {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 0;
  border-bottom: var(--border);
}

.section-aside {
  border-right: var(--border);
  padding: 3rem 2rem;
}

.section-aside p {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--gray-400);
  margin-bottom: 1.5rem;
}

.section-aside nav a {
  display: block;
  padding: 0.5rem 0;
  font-size: 0.875rem;
  border-bottom: 1px solid var(--gray-200);
  min-height: 40px;
  display: flex;
  align-items: center;
}

.section-aside nav a:hover {
  border-bottom-color: var(--black);
}

.home-content-body {
  padding: 3rem 2.5rem;
  max-width: 800px;
}

.home-content-body h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  line-height: 1.25;
}

/* ===== 频道卡片区 ===== */
.channels-section {
  padding: 4rem 2.5rem;
  border-bottom: var(--border);
}

.channels-section > small { margin-bottom: 0.5rem; }

.channels-section > h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 2.5rem;
}

.channels-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 0;
}

.channel-card {
  border: var(--border);
  margin: -1px 0 0 -1px;
  padding: 2rem;
  transition: background var(--transition);
}

.channel-card:hover {
  background: var(--gray-100);
}

.channel-card h3 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  line-height: 1.3;
}

.channel-card h3 a {
  border-bottom: none;
}

.channel-card h3 a:hover {
  border-bottom: 1px solid var(--black);
}

.channel-card p {
  font-size: 0.875rem;
  color: var(--gray-600);
  line-height: 1.6;
}

/* ===== 最新文章区 ===== */
.latest-section {
  padding: 4rem 2.5rem;
  border-bottom: var(--border);
}

.latest-section > small { margin-bottom: 0.5rem; }

.latest-section > h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 2.5rem;
}

.cards-flow {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 0;
}

/* ===== 卡片通用 ===== */
.home-card,
.ch-article-card,
.related-card,
.tag-article-card {
  border: var(--border);
  margin: -1px 0 0 -1px;
  display: flex;
  flex-direction: column;
  transition: background var(--transition);
}

.home-card:hover,
.ch-article-card:hover,
.related-card:hover,
.tag-article-card:hover {
  background: var(--gray-100);
}

.card-figure {
  margin: 0;
  overflow: hidden;
  border-bottom: var(--border);
  aspect-ratio: 16 / 9;
}

.card-figure .card-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 240ms ease;
}

.home-card:hover .card-img,
.ch-article-card:hover .card-img {
  transform: scale(1.03);
}

.card-body {
  padding: 1.5rem;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.card-date {
  font-size: 0.75rem;
  color: var(--gray-400);
  letter-spacing: 0.03em;
}

.card-body h3 {
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.35;
}

.card-body h3 a {
  border-bottom: none;
  transition: opacity var(--transition);
}

.card-body h3 a:hover {
  opacity: 0.6;
  border-bottom: none;
}

.card-desc {
  font-size: 0.875rem;
  color: var(--gray-600);
  line-height: 1.6;
  flex: 1;
}

.card-link {
  font-size: 0.8125rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  border-bottom: 1px solid var(--black);
  align-self: flex-start;
  margin-top: 0.5rem;
  min-height: 32px;
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0;
}

/* ===== 频道页 ===== */
.ch-hero {
  background: var(--black);
  min-height: 40vh;
  position: relative;
}

.ch-hero-figure {
  margin: 0;
  min-height: 40vh;
  display: grid;
  grid-template-columns: 2fr 1fr;
  align-items: end;
}

.ch-hero-cap {
  padding: 4rem 3rem 3rem;
  color: var(--white);
}

.ch-hero-cap h1 {
  font-family: var(--font-brand);
  font-size: clamp(1.375rem, 3vw, 2.5rem);
  font-weight: 700;
  color: var(--white);
  line-height: 1.2;
  word-break: break-all;
}

.ch-hero-aside {
  padding: 2rem 2rem 3rem;
  border-left: 1px solid rgba(255,255,255,0.15);
}

.ch-hero-aside small { color: rgba(255,255,255,0.5); }

.ch-hero-aside p {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.7);
  line-height: 1.6;
  margin-bottom: 1rem;
}

.ch-hero-aside a {
  color: rgba(255,255,255,0.6);
  font-size: 0.875rem;
  border-bottom: 1px solid rgba(255,255,255,0.3);
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0;
}

.ch-hero-aside a:hover {
  color: var(--white);
  border-bottom-color: var(--white);
}

.ch-content-section {
  display: grid;
  grid-template-columns: 1fr 2.5fr;
  gap: 0;
  border-bottom: var(--border);
}

.ch-aside,
.about-aside,
.privacy-aside,
.tag-aside,
.article-aside {
  border-right: var(--border);
  padding: 2.5rem 1.75rem;
}

.ch-aside h3,
.about-aside h3,
.privacy-aside h3,
.tag-aside h3,
.article-aside h3 {
  font-size: 0.9375rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

.ch-aside hr,
.about-aside hr,
.privacy-aside hr,
.tag-aside hr,
.article-aside hr {
  border: none;
  border-top: var(--border);
  margin: 1.5rem 0;
}

.aside-menu {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.aside-menu li a {
  display: flex;
  align-items: center;
  font-size: 0.875rem;
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--gray-200);
  min-height: 40px;
  line-height: 1.4;
  transition: border-bottom-color var(--transition);
}

.aside-menu li a:hover {
  border-bottom-color: var(--black);
}

.ch-main-body,
.about-main-body,
.privacy-main-body,
.tag-main-body {
  padding: 2.5rem 2.5rem 3rem;
  max-width: 760px;
}

.ch-main-body h2,
.about-main-body h2,
.tag-main-body h2 {
  font-size: 1.375rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
}

.ch-articles-section,
.tag-articles-section {
  padding: 3rem 2.5rem 4rem;
}

.ch-articles-section > small,
.tag-articles-section > small {
  margin-bottom: 0.5rem;
}

.ch-articles-section > h2,
.tag-articles-section > h2 {
  font-size: 1.375rem;
  font-weight: 700;
  margin-bottom: 2rem;
}

.ch-articles-section .ch-article-card,
.tag-articles-section .tag-article-card {
  margin-bottom: 0;
}

/* channel articles grid */
.ch-articles-section {
  display: flex;
  flex-direction: column;
}

.ch-articles-section .ch-article-card {
  flex-direction: row;
  border: var(--border);
  margin-top: -1px;
}

.ch-article-card .card-figure {
  width: 220px;
  flex-shrink: 0;
  border-bottom: none;
  border-right: var(--border);
  aspect-ratio: auto;
}

/* ===== 文章页 ===== */
.article-header-section {
  background: var(--black);
  min-height: 35vh;
  position: relative;
}

.article-header-figure {
  margin: 0;
  min-height: 35vh;
  display: grid;
  grid-template-columns: 2.5fr 1fr;
  align-items: end;
  position: relative;
}

.article-hero-img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.25;
}

.article-header-cap {
  position: relative;
  z-index: 2;
  padding: 3rem 3rem 2.5rem;
  color: var(--white);
}

.article-header-cap h1 {
  font-family: var(--font-brand);
  font-size: clamp(1.25rem, 2.5vw, 2.25rem);
  font-weight: 700;
  color: var(--white);
  line-height: 1.25;
  margin-top: 1rem;
  margin-bottom: 1rem;
  word-break: break-all;
}

.breadcrumb {
  font-size: 0.8125rem;
  color: rgba(255,255,255,0.55);
}

.breadcrumb a {
  color: rgba(255,255,255,0.55);
  border-bottom: 1px solid rgba(255,255,255,0.2);
}

.breadcrumb a:hover {
  color: var(--white);
  border-bottom-color: var(--white);
}

.article-meta {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  font-size: 0.8125rem;
  color: rgba(255,255,255,0.55);
}

.mod-date {
  color: rgba(255,255,255,0.4);
}

.article-header-aside {
  position: relative;
  z-index: 2;
  padding: 2rem 1.75rem 2.5rem;
  border-left: 1px solid rgba(255,255,255,0.15);
}

.article-header-aside small { color: rgba(255,255,255,0.5); }

.article-header-aside h3 {
  font-size: 0.875rem;
  font-weight: 700;
  color: rgba(255,255,255,0.8);
  margin-bottom: 1rem;
}

.article-header-aside .aside-menu li a {
  color: rgba(255,255,255,0.65);
  border-bottom-color: rgba(255,255,255,0.15);
}

.article-header-aside .aside-menu li a:hover {
  color: var(--white);
  border-bottom-color: var(--white);
}

.article-body-section {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 0;
  border-bottom: var(--border);
}

.article-aside {
  padding: 2.5rem 1.5rem;
}

.article-aside > a {
  display: flex;
  align-items: center;
  min-height: 40px;
  font-size: 0.875rem;
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--gray-200);
}

.article-content {
  padding: 3rem 3rem 4rem;
  max-width: 780px;
  min-width: 0;
}

.related-section {
  padding: 3rem 2.5rem 4rem;
  border-bottom: var(--border);
}

.related-section > small { margin-bottom: 0.5rem; }

.related-section > h2 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 2rem;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 0;
}

.related-card {
  padding: 1.5rem;
  flex-direction: column;
}

.related-card h3 {
  font-size: 0.9375rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
}

.related-card h3 a { border-bottom: none; }
.related-card h3 a:hover { border-bottom: 1px solid var(--black); }

.related-card p {
  font-size: 0.8125rem;
  color: var(--gray-600);
  line-height: 1.6;
}

/* ===== About ===== */
.about-intro-section {
  background: var(--black);
  min-height: 32vh;
}

.about-intro-figure {
  margin: 0;
  min-height: 32vh;
  display: grid;
  grid-template-columns: 2fr 1fr;
  align-items: end;
}

.about-intro-cap {
  padding: 4rem 3rem 3rem;
  color: var(--white);
}

.about-intro-cap h1 {
  font-family: var(--font-brand);
  font-size: clamp(1.25rem, 2.5vw, 2rem);
  font-weight: 700;
  color: var(--white);
  line-height: 1.25;
  margin-top: 0.75rem;
  word-break: break-all;
}

.about-intro-aside {
  padding: 2rem 2rem 3rem;
  border-left: 1px solid rgba(255,255,255,0.15);
}

.about-intro-aside p {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.65);
  margin-bottom: 1rem;
  line-height: 1.6;
}

.about-intro-aside a {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.6);
  border-bottom: 1px solid rgba(255,255,255,0.25);
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0;
}

.about-intro-aside a:hover {
  color: var(--white);
  border-bottom-color: var(--white);
}

.about-content-section {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 0;
  border-bottom: var(--border);
}

/* ===== Privacy ===== */
.privacy-header-section {
  background: var(--black);
  min-height: 28vh;
}

.privacy-header-figure {
  margin: 0;
  min-height: 28vh;
  display: grid;
  grid-template-columns: 2fr 1fr;
  align-items: end;
}

.privacy-header-cap {
  padding: 3.5rem 3rem 2.5rem;
  color: var(--white);
}

.privacy-header-cap h1 {
  font-family: var(--font-brand);
  font-size: clamp(1.25rem, 2.5vw, 2rem);
  font-weight: 700;
  color: var(--white);
  margin-top: 0.75rem;
  word-break: break-all;
}

.privacy-date {
  font-size: 0.8125rem;
  color: rgba(255,255,255,0.55);
  margin-top: 0.75rem;
}

.privacy-header-aside {
  padding: 2rem 2rem 2.5rem;
  border-left: 1px solid rgba(255,255,255,0.15);
}

.privacy-header-aside p {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.65);
  margin-bottom: 1rem;
}

.privacy-header-aside a {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.6);
  border-bottom: 1px solid rgba(255,255,255,0.25);
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0;
}

.privacy-header-aside a:hover {
  color: var(--white);
  border-bottom-color: var(--white);
}

.privacy-content-section {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 0;
  border-bottom: var(--border);
}

/* ===== Tag ===== */
.tag-header-section {
  background: var(--black);
  min-height: 30vh;
}

.tag-header-figure {
  margin: 0;
  min-height: 30vh;
  display: grid;
  grid-template-columns: 2fr 1fr;
  align-items: end;
}

.tag-header-cap {
  padding: 3.5rem 3rem 2.5rem;
  color: var(--white);
}

.tag-header-cap h1 {
  font-family: var(--font-brand);
  font-size: clamp(1.25rem, 2.5vw, 2rem);
  font-weight: 700;
  color: var(--white);
  margin-top: 0.75rem;
  word-break: break-all;
}

.tag-header-cap p {
  font-size: 0.9375rem;
  color: rgba(255,255,255,0.7);
  margin-top: 0.75rem;
}

.tag-header-aside {
  padding: 2rem 2rem 2.5rem;
  border-left: 1px solid rgba(255,255,255,0.15);
}

.tag-header-aside p {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.65);
  margin-bottom: 1rem;
}

.tag-header-aside a {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.6);
  border-bottom: 1px solid rgba(255,255,255,0.25);
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0;
}

.tag-header-aside a:hover {
  color: var(--white);
  border-bottom-color: var(--white);
}

.tag-content-section {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 0;
  border-bottom: var(--border);
}

.tag-article-card {
  border: var(--border);
  margin-top: -1px;
  padding: 1.5rem;
  flex-direction: row;
  gap: 0;
}

.tag-article-card .card-body {
  padding: 0;
}

/* ===== 正文内容样式 ===== */
.page-content {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--black);
}

.page-content h2 {
  font-size: 1.375rem;
  font-weight: 700;
  margin: 2.5rem 0 1rem;
  line-height: 1.25;
}

.page-content h3 {
  font-size: 1.125rem;
  font-weight: 700;
  margin: 2rem 0 0.75rem;
  line-height: 1.3;
}

.page-content p {
  margin-bottom: 1.25rem;
}

.page-content ul,
.page-content ol {
  margin: 1rem 0 1.25rem 1.5rem;
  list-style: disc;
}

.page-content ol { list-style: decimal; }

.page-content li {
  margin-bottom: 0.5rem;
  line-height: 1.7;
}

.page-content a {
  border-bottom: 1px solid var(--black);
}

.page-content strong { font-weight: 700; }

.page-content blockquote {
  border-left: 3px solid var(--black);
  padding-left: 1.5rem;
  margin: 1.5rem 0;
  color: var(--gray-600);
  font-style: italic;
}

.page-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.9375rem;
}

.page-content th,
.page-content td {
  border: var(--border);
  padding: 0.625rem 1rem;
  text-align: left;
}

.page-content th {
  background: var(--black);
  color: var(--white);
  font-weight: 700;
}

/* ===== 页脚 ===== */
.site-footer {
  background: var(--black);
  color: var(--white);
  margin-top: auto;
}

.footer-brand {
  padding: 2.5rem 2.5rem 1.5rem;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.footer-big-brand {
  font-family: var(--font-brand);
  font-size: clamp(1.25rem, 2vw, 1.75rem);
  font-weight: 700;
  color: var(--white);
  letter-spacing: -0.01em;
  word-break: break-all;
}

.footer-meta {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  flex-wrap: wrap;
  padding: 1.25rem 2.5rem;
  font-size: 0.8125rem;
  color: rgba(255,255,255,0.5);
}

.footer-meta a {
  color: rgba(255,255,255,0.65);
  border-bottom: 1px solid rgba(255,255,255,0.2);
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0;
}

.footer-meta a:hover {
  color: var(--white);
  border-bottom-color: var(--white);
}

/* ===== default section ===== */
.default-section {
  padding: 4rem 3rem;
}

.default-figure {
  margin: 0 0 2rem;
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 2rem;
  align-items: start;
}

.default-figure figcaption h1 {
  font-size: clamp(1.375rem, 2vw, 2rem);
  font-weight: 700;
}

.default-aside a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  font-size: 0.9375rem;
  border-bottom: 1px solid var(--black);
  padding: 0.25rem 0;
}

/* ===== 响应式 ===== */
@media (max-width: 900px) {
  :root { --nav-width: 0px; }

  .nav-details {
    width: 100%;
    height: auto;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 200;
    flex-direction: column;
  }

  .nav-toggle {
    padding: 0.875rem 1.25rem;
  }

  .nav-details:not([open]) .nav-menu {
    display: none;
  }

  .nav-details[open] .nav-menu {
    display: flex;
    max-height: 60vh;
    overflow-y: auto;
    background: var(--black);
  }

  .content-shift {
    margin-left: 0;
    padding-top: 56px;
  }

  .hero-figure,
  .ch-hero-figure,
  .article-header-figure,
  .about-intro-figure,
  .privacy-header-figure,
  .tag-header-figure,
  .default-figure {
    grid-template-columns: 1fr;
  }

  .hero-caption {
    grid-column: 1;
    text-align: left;
    padding: 3rem 1.5rem 2rem;
  }

  .hero-aside {
    display: none;
  }

  .ch-hero-aside,
  .article-header-aside,
  .about-intro-aside,
  .privacy-header-aside,
  .tag-header-aside {
    display: none;
  }

  .ch-hero-cap { padding: 3rem 1.5rem 2.5rem; }
  .article-header-cap { padding: 3rem 1.5rem 2.5rem; }
  .about-intro-cap { padding: 3rem 1.5rem 2.5rem; }
  .privacy-header-cap { padding: 3rem 1.5rem 2.5rem; }
  .tag-header-cap { padding: 3rem 1.5rem 2.5rem; }

  .home-content-section,
  .ch-content-section,
  .article-body-section,
  .about-content-section,
  .privacy-content-section,
  .tag-content-section {
    grid-template-columns: 1fr;
  }

  .section-aside,
  .ch-aside,
  .article-aside,
  .about-aside,
  .privacy-aside,
  .tag-aside {
    border-right: none;
    border-bottom: var(--border);
  }

  .home-content-body { padding: 2rem 1.5rem; }
  .ch-main-body,
  .about-main-body,
  .privacy-main-body,
  .tag-main-body { padding: 2rem 1.5rem; }

  .article-content { padding: 2rem 1.5rem; }

  .channels-section,
  .latest-section,
  .ch-articles-section,
  .tag-articles-section,
  .related-section { padding: 2.5rem 1.5rem; }

  .channels-grid,
  .cards-flow,
  .related-grid {
    grid-template-columns: 1fr;
  }

  .channel-card,
  .home-card { margin: 0 0 -1px 0; }

  .ch-article-card {
    flex-direction: column;
  }

  .ch-article-card .card-figure {
    width: 100%;
    border-right: none;
    border-bottom: var(--border);
    aspect-ratio: 16 / 9;
  }

  .footer-meta {
    gap: 1rem;
    padding: 1rem 1.5rem;
    flex-direction: column;
    align-items: flex-start;
  }

  .footer-brand { padding: 2rem 1.5rem 1.25rem; }

  .default-section { padding: 2.5rem 1.5rem; }
  .default-figure { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .hero-section, .hero-figure { min-height: 60vh; }
  .hero-caption h1 { font-size: 1.375rem; }
  .ch-hero, .ch-hero-figure { min-height: 30vh; }
  .article-header-section, .article-header-figure { min-height: 28vh; }
}

/* ===== prefers-reduced-motion ===== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    transition-duration: 1ms !important;
    animation-duration: 1ms !important;
  }
  html { scroll-behavior: auto; }
}