@import url('https://fonts.googleapis.com/css2?family=Cormorant:wght@400;500;600;700&family=Montserrat:wght@300;400;500;600;700&display=swap');

/* ============================================================
   CSS 变量 & 基础重置
   ============================================================ */
:root {
  --black: #000000;
  --deep: #121212;
  --surface: #1a1a2e;
  --surface2: #16213e;
  --midnight: #0d1b3e;
  --accent: #4a6fa5;
  --accent-bright: #6a9fd8;
  --accent-gold: #c9a84c;
  --accent-glow: #7eb8f7;
  --neon-blue: #4fc3f7;
  --neon-gold: #ffd54f;
  --text-primary: #f0f0f0;
  --text-secondary: #b0b8c8;
  --text-muted: #6e7a8a;
  --border: #2a3a5c;
  --border-bright: #4a6fa5;
  --radius-card: 18px;
  --radius-btn: 8px;
  --font-serif: 'Cormorant', 'SimSun', 'STSong', serif;
  --font-sans: 'Montserrat', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --header-h: 64px;
  --anchor-h: 44px;
  --transition: 0.28s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  color-scheme: dark;
  font-size: 16px;
  scroll-padding-top: calc(var(--header-h) + var(--anchor-h) + 8px);
}

body {
  background: var(--black);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-weight: 400;
  line-height: 1.7;
  min-height: 100vh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

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

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

a:hover, a:focus-visible {
  color: var(--neon-blue);
  text-decoration: underline;
  outline: none;
}

a:focus-visible {
  outline: 2px solid var(--accent-bright);
  outline-offset: 3px;
  border-radius: 3px;
}

ul, ol {
  list-style: none;
}

h1, h2, h3, h4 {
  font-family: var(--font-serif);
  font-weight: 600;
  line-height: 1.3;
  color: var(--text-primary);
}

/* ============================================================
   站点骨架
   ============================================================ */
.site-wrapper {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* ============================================================
   顶部导航
   ============================================================ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-h);
  background: rgba(0, 0, 0, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  gap: 24px;
}

.brand-link {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  text-decoration: none;
}

.brand-logo-img {
  height: 40px;
  width: auto;
}

.brand-text-logo {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: 0.04em;
  text-shadow: 0 0 10px rgba(106, 159, 216, 0.4);
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  flex: 1;
  justify-content: flex-end;
}

.nav-links-wrap {
  display: flex;
  align-items: center;
  gap: 2px;
  flex-wrap: wrap;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 5px;
  padding: 10px 12px;
  min-height: 44px;
  color: var(--text-secondary);
  font-size: 0.82rem;
  font-weight: 500;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  text-decoration: none;
  border-radius: var(--radius-btn);
  transition: color var(--transition), background var(--transition);
  white-space: nowrap;
}

.nav-link:hover, .nav-link:focus-visible {
  color: var(--text-primary);
  background: rgba(74, 111, 165, 0.15);
  text-decoration: none;
}

.nav-icon {
  font-size: 0.9em;
  opacity: 0.7;
}

.nav-cta {
  margin-left: 12px;
  padding: 10px 20px;
  min-height: 44px;
  display: flex;
  align-items: center;
  background: linear-gradient(135deg, var(--accent) 0%, var(--surface2) 100%);
  color: var(--text-primary) !important;
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  border: 1px solid var(--border-bright);
  border-radius: var(--radius-btn);
  text-decoration: none;
  white-space: nowrap;
  transition: background var(--transition), box-shadow var(--transition), transform var(--transition);
}

.nav-cta:hover, .nav-cta:focus-visible {
  background: linear-gradient(135deg, var(--accent-bright) 0%, var(--midnight) 100%);
  box-shadow: 0 0 16px rgba(79, 195, 247, 0.25);
  transform: translateY(-1px);
  text-decoration: none;
  color: var(--text-primary) !important;
}

/* 汉堡按钮（移动端） */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-btn);
  cursor: pointer;
  margin-left: auto;
  padding: 8px;
}

.toggle-bar {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-secondary);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

/* ============================================================
   粘性锚点条
   ============================================================ */
.sticky-anchor-bar {
  position: sticky;
  top: var(--header-h);
  z-index: 900;
  height: var(--anchor-h);
  background: rgba(18, 18, 18, 0.96);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
  overflow-x: auto;
  scrollbar-width: none;
}

.sticky-anchor-bar::-webkit-scrollbar {
  display: none;
}

.anchor-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  gap: 0;
}

.anchor-link {
  display: flex;
  align-items: center;
  padding: 8px 14px;
  min-height: 44px;
  color: var(--text-muted);
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  text-decoration: none;
  white-space: nowrap;
  border-bottom: 2px solid transparent;
  transition: color var(--transition), border-color var(--transition);
}

.anchor-link:hover, .anchor-link:focus-visible {
  color: var(--accent-bright);
  border-bottom-color: var(--accent-bright);
  text-decoration: none;
}

/* ============================================================
   Hero 区域
   ============================================================ */
.hero-section {
  position: relative;
  min-height: 45vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  margin-top: calc(var(--header-h) + var(--anchor-h));
  background: var(--midnight);
}

.hero-media {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: brightness(0.45) saturate(0.8);
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    160deg,
    rgba(0,0,0,0.7) 0%,
    rgba(13,27,62,0.6) 50%,
    rgba(0,0,0,0.8) 100%
  );
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 60px 24px 80px;
  max-width: 800px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 16px;
  margin-bottom: 20px;
  background: rgba(74, 111, 165, 0.2);
  border: 1px solid var(--border-bright);
  border-radius: 20px;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--neon-blue);
  text-shadow: 0 0 10px rgba(79, 195, 247, 0.5);
}

.hero-h1 {
  font-family: var(--font-serif);
  font-size: clamp(2rem, 6vw, 3.8rem);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 16px;
  text-shadow: 0 0 10px rgba(106, 159, 216, 0.3);
  letter-spacing: 0.02em;
}

.hero-desc {
  font-size: 1rem;
  color: var(--text-secondary);
  margin-bottom: 28px;
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.7;
}

.hero-cta-btn {
  display: inline-flex;
  align-items: center;
  padding: 14px 36px;
  min-height: 48px;
  background: linear-gradient(135deg, var(--accent) 0%, var(--midnight) 100%);
  color: var(--text-primary);
  font-size: 0.92rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border: 1px solid var(--accent-bright);
  border-radius: var(--radius-btn);
  text-decoration: none;
  transition: box-shadow var(--transition), transform var(--transition), background var(--transition);
}

.hero-cta-btn:hover, .hero-cta-btn:focus-visible {
  box-shadow: 0 0 24px rgba(79, 195, 247, 0.35);
  transform: translateY(-2px);
  background: linear-gradient(135deg, var(--accent-bright) 0%, var(--midnight) 100%);
  color: var(--text-primary);
  text-decoration: none;
}

/* 圆弧底边 */
.hero-arc {
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  z-index: 3;
  height: 60px;
  background: var(--black);
  clip-path: ellipse(55% 100% at 50% 100%);
}

/* ============================================================
   主体内容
   ============================================================ */
.site-main {
  flex: 1;
  background: var(--black);
}

.wrap {
  max-width: 1280px;
  margin: 0 auto;
  padding: 48px 24px 64px;
}

/* main > article.wrap > div > section 四层结构 */
.content-section {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 40px;
  align-items: start;
}

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

.content-body {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text-secondary);
}

/* 正文内的标题样式 */
.content-body h2 {
  font-family: var(--font-serif);
  font-size: 1.75rem;
  color: var(--text-primary);
  margin: 2.5em 0 0.8em;
  padding-bottom: 0.4em;
  border-bottom: 1px solid var(--border);
  scroll-margin-top: calc(var(--header-h) + var(--anchor-h) + 12px);
}

.content-body h2 > span {
  display: block;
}

.content-body h3 {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  color: var(--text-primary);
  margin: 2em 0 0.6em;
  scroll-margin-top: calc(var(--header-h) + var(--anchor-h) + 12px);
}

.content-body h3 > span {
  display: inline;
}

.content-body p {
  margin-bottom: 1em;
  font-size: 1rem;
}

.content-body ul, .content-body ol {
  margin-bottom: 1em;
  padding-left: 1.5em;
}

.content-body ul {
  list-style: disc;
}

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

.content-body li {
  margin-bottom: 0.4em;
}

.content-body strong {
  color: var(--text-primary);
  font-weight: 600;
}

.content-body a {
  color: var(--accent-bright);
  border-bottom: 1px solid rgba(106, 159, 216, 0.3);
  text-decoration: none;
  transition: color var(--transition), border-color var(--transition);
}

.content-body a:hover {
  color: var(--neon-blue);
  border-bottom-color: var(--neon-blue);
  text-decoration: none;
}

/* div 区块分隔 */
.content-body div {
  padding-top: 16px;
  margin-bottom: 48px;
  border-top: 1px solid rgba(42, 58, 92, 0.5);
  scroll-margin-top: calc(var(--header-h) + var(--anchor-h) + 12px);
}

.content-body div:first-child {
  border-top: none;
  padding-top: 0;
}

/* ============================================================
   侧边栏
   ============================================================ */
.content-aside {
  position: sticky;
  top: calc(var(--header-h) + var(--anchor-h) + 20px);
  display: flex;
  flex-direction: column;
  gap: 24px;
}

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

.aside-title {
  font-family: var(--font-serif);
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}

.aside-title > span {
  display: inline;
}

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

.aside-link {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  min-height: 40px;
  color: var(--text-secondary);
  font-size: 0.88rem;
  text-decoration: none;
  border-radius: 8px;
  transition: background var(--transition), color var(--transition);
}

.aside-link:hover, .aside-link:focus-visible {
  background: rgba(74, 111, 165, 0.12);
  color: var(--accent-bright);
  text-decoration: none;
}

.aside-arrow {
  color: var(--accent);
  font-size: 1.1em;
  flex-shrink: 0;
}

.aside-tip {
  background: rgba(13, 27, 62, 0.6);
  border-color: rgba(74, 111, 165, 0.3);
}

.aside-tip p {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* ============================================================
   页脚
   ============================================================ */
.site-footer {
  background: var(--deep);
  border-top: 1px solid var(--border);
}

.footer-nav-wrap {
  max-width: 1280px;
  margin: 0 auto;
  padding: 48px 24px 32px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

/* footer nav > dl > dt/dd > a 结构 */
.footer-nav-wrap dl {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.footer-nav-wrap dt {
  font-family: var(--font-serif);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 8px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}

.footer-nav-wrap dd {
  padding: 0;
}

.footer-nav-wrap dd a {
  display: flex;
  align-items: center;
  padding: 8px 4px;
  min-height: 40px;
  color: var(--text-muted);
  font-size: 0.86rem;
  text-decoration: none;
  transition: color var(--transition);
}

.footer-nav-wrap dd a:hover,
.footer-nav-wrap dd a:focus-visible {
  color: var(--accent-bright);
  text-decoration: none;
}

.footer-bottom {
  max-width: 1280px;
  margin: 0 auto;
  padding: 20px 24px;
  border-top: 1px solid var(--border);
  text-align: center;
}

.footer-copy {
  color: var(--text-muted);
  font-size: 0.82rem;
  line-height: 1.6;
}

/* ============================================================
   动效 —— Stagger List + Subtle Parallax
   ============================================================ */
@media (prefers-reduced-motion: no-preference) {
  .content-body div {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.55s ease, transform 0.55s ease;
  }

  .content-body div.in-view {
    opacity: 1;
    transform: translateY(0);
  }

  .hero-content {
    animation: heroFadeIn 0.8s ease both;
  }

  @keyframes heroFadeIn {
    from {
      opacity: 0;
      transform: translateY(20px);
    }
    to {
      opacity: 1;
      transform: translateY(0);
    }
  }

  .aside-card {
    animation: asideFadeIn 0.7s 0.3s ease both;
  }

  @keyframes asideFadeIn {
    from {
      opacity: 0;
      transform: translateX(16px);
    }
    to {
      opacity: 1;
      transform: translateX(0);
    }
  }
}

/* ============================================================
   响应式：平板
   ============================================================ */
@media (max-width: 1024px) {
  .content-section {
    grid-template-columns: 1fr 260px;
    gap: 28px;
  }

  .nav-text {
    display: none;
  }

  .nav-link {
    padding: 10px 10px;
  }
}

/* ============================================================
   响应式：移动端
   ============================================================ */
@media (max-width: 768px) {
  :root {
    --header-h: 56px;
    --anchor-h: 44px;
  }

  .nav-toggle {
    display: flex;
  }

  .main-nav {
    display: none;
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    background: rgba(0, 0, 0, 0.97);
    border-bottom: 1px solid var(--border);
    padding: 16px;
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    z-index: 999;
  }

  .main-nav.nav-open {
    display: flex;
  }

  .nav-links-wrap {
    flex-direction: column;
    gap: 0;
  }

  .nav-link {
    justify-content: flex-start;
    width: 100%;
    padding: 12px 16px;
    min-height: 48px;
  }

  .nav-text {
    display: inline;
  }

  .nav-cta {
    margin-left: 0;
    margin-top: 8px;
    justify-content: center;
    min-height: 48px;
  }

  .content-section {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .content-aside {
    position: static;
    flex-direction: row;
    flex-wrap: wrap;
    gap: 16px;
  }

  .aside-card {
    flex: 1 1 280px;
  }

  .hero-section {
    min-height: 45vh;
  }

  .hero-content {
    padding: 48px 20px 72px;
  }

  .hero-h1 {
    font-size: 1.8rem;
  }

  .hero-desc {
    font-size: 0.94rem;
  }

  .footer-nav-wrap {
    grid-template-columns: 1fr;
    gap: 24px;
    padding: 32px 20px 24px;
  }

  .wrap {
    padding: 32px 20px 48px;
  }

  .anchor-inner {
    padding: 0 16px;
  }

  .anchor-link {
    padding: 8px 10px;
    font-size: 0.72rem;
  }

  .header-inner {
    padding: 0 16px;
  }
}

@media (max-width: 375px) {
  .hero-h1 {
    font-size: 1.5rem;
  }

  .hero-badge {
    font-size: 0.7rem;
    padding: 4px 12px;
  }

  .content-body h2 {
    font-size: 1.4rem;
  }
}

/* ============================================================
   打印优化
   ============================================================ */
@media print {
  .site-header,
  .sticky-anchor-bar,
  .content-aside,
  .site-footer {
    display: none;
  }

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

  body {
    background: #fff;
    color: #000;
  }
}