```css
/* ============================================
   星辰影视 - 主样式表
   设计风格：深空科技感 / 渐变 / 毛玻璃 / 响应式
   作者：星辰影视 UI 设计组
   版本：2.0
   ============================================ */

/* ---------- CSS 变量（主题令牌） ---------- */
:root {
  --bg: #f5f7fc;
  --bg2: #ffffff;
  --text: #1a1e2b;
  --muted: #4a5268;
  --accent: #0b1a2f;
  --accent2: #2d4b7c;
  --card: #ffffff;
  --border: #e1e6f0;
  --shadow: rgba(20, 30, 60, 0.08);
  --hero-grad: radial-gradient(circle at 20% 30%, #0b1a2f, #152a44);
  --svg-filter: none;
  --glass-bg: rgba(255, 255, 255, 0.7);
  --glass-border: rgba(255, 255, 255, 0.3);
  --btn-primary-bg: #ffffff;
  --btn-primary-text: #0b1a2f;
  --btn-secondary-border: rgba(255, 255, 255, 0.5);
  --btn-secondary-text: #ffffff;
  --footer-bg: #f0f2f8;
  --input-bg: #ffffff;
  --scrollbar-thumb: #c1c9d6;
  --scrollbar-track: transparent;
  --overlay: rgba(11, 26, 47, 0.6);
  --badge-bg: rgba(45, 75, 124, 0.1);
  --badge-text: #2d4b7c;
  --link-hover: #1f6feb;
  --card-hover-shadow: rgba(20, 30, 60, 0.15);
  --transition-fast: 0.2s ease;
  --transition-slow: 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

/* 暗色模式变量覆盖 */
[data-theme="dark"] {
  --bg: #0d1117;
  --bg2: #161b22;
  --text: #e6edf3;
  --muted: #9aa4b2;
  --accent: #1f6feb;
  --accent2: #58a6ff;
  --card: #1c2129;
  --border: #30363d;
  --shadow: rgba(0, 0, 0, 0.5);
  --hero-grad: radial-gradient(circle at 20% 30%, #0a0f1a, #101b2b);
  --svg-filter: none;
  --glass-bg: rgba(22, 27, 34, 0.7);
  --glass-border: rgba(48, 54, 61, 0.5);
  --btn-primary-bg: #1f6feb;
  --btn-primary-text: #ffffff;
  --btn-secondary-border: rgba(88, 166, 255, 0.5);
  --btn-secondary-text: #58a6ff;
  --footer-bg: #0d1117;
  --input-bg: #0d1117;
  --scrollbar-thumb: #30363d;
  --overlay: rgba(0, 0, 0, 0.7);
  --badge-bg: rgba(88, 166, 255, 0.15);
  --badge-text: #58a6ff;
  --link-hover: #58a6ff;
  --card-hover-shadow: rgba(0, 0, 0, 0.7);
}

/* ---------- 基础重置与全局 ---------- */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  -webkit-tap-highlight-color: transparent;
}

body {
  font-family: system-ui, -apple-system, 'PingFang SC', 'Microsoft YaHei', 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  transition: background 0.3s ease, color 0.3s ease;
  overflow-x: hidden;
  min-height: 100vh;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* 链接与选中状态 */
a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

::selection {
  background: var(--accent2);
  color: #fff;
}

/* 滚动条 */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--scrollbar-track);
}

::-webkit-scrollbar-thumb {
  background: var(--scrollbar-thumb);
  border-radius: 10px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--accent2);
}

/* 容器 */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  width: 100%;
}

/* 图片懒加载 */
.lazy {
  opacity: 0;
  transition: opacity 0.3s ease;
}

.lazy.loaded {
  opacity: 1;
}

/* ---------- 导航栏（毛玻璃吸顶） ---------- */
.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--glass-bg);
  backdrop-filter: blur(12px) saturate(180%);
  -webkit-backdrop-filter: blur(12px) saturate(180%);
  border-bottom: 1px solid var(--glass-border);
  box-shadow: 0 2px 12px var(--shadow);
  transition: background 0.3s ease, border-color 0.3s ease;
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  gap: 16px;
}

/* Logo */
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.logo svg {
  width: 36px;
  height: 36px;
  transition: transform 0.3s ease;
}

.logo:hover svg {
  transform: rotate(10deg) scale(1.05);
}

.logo span {
  font-weight: 700;
  font-size: 1.25rem;
  letter-spacing: 0.5px;
  background: linear-gradient(135deg, var(--accent2), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  white-space: nowrap;
}

/* 导航链接 */
.nav-links {
  display: flex;
  gap: 28px;
  font-weight: 500;
  font-size: 0.95rem;
}

.nav-links a {
  position: relative;
  padding: 6px 0;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent2);
  transition: width 0.3s ease;
}

.nav-links a:hover::after {
  width: 100%;
}

/* 导航操作区 */
.nav-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

/* 搜索框 */
.search-box {
  display: flex;
  align-items: center;
  background: var(--input-bg);
  border-radius: 40px;
  padding: 6px 14px;
  border: 1px solid var(--border);
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
  gap: 6px;
}

.search-box:focus-within {
  border-color: var(--accent2);
  box-shadow: 0 0 0 3px rgba(88, 166, 255, 0.15);
}

.search-box input {
  border: none;
  background: transparent;
  outline: none;
  color: var(--text);
  width: 120px;
  font-size: 0.9rem;
  transition: width 0.3s ease;
}

.search-box input::placeholder {
  color: var(--muted);
}

.search-box svg {
  width: 16px;
  height: 16px;
  opacity: 0.6;
  flex-shrink: 0;
}

/* 图标按钮 */
.icon-btn {
  background: var(--input-bg);
  border: 1px solid var(--border);
  cursor: pointer;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-fast);
  color: var(--text);
  flex-shrink: 0;
}

.icon-btn:hover {
  border-color: var(--accent2);
  color: var(--accent2);
  transform: scale(1.05);
}

.icon-btn svg {
  width: 20px;
  height: 20px;
}

/* 移动菜单按钮 */
.mobile-menu {
  display: none;
}

/* ---------- 面包屑 ---------- */
.breadcrumb {
  display: flex;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--muted);
  margin: 20px 0 0;
  flex-wrap: wrap;
  align-items: center;
}

.breadcrumb span:last-child {
  color: var(--text);
  font-weight: 500;
}

/* ---------- Hero 区域 ---------- */
.hero {
  background: var(--hero-grad);
  color: #ffffff;
  padding: 72px 0 64px;
  margin-bottom: 40px;
  position: relative;
  overflow: hidden;
}

/* 动态星空背景效果 */
.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image:
    radial-gradient(2px 2px at 20px 30px, rgba(255, 255, 255, 0.3), transparent),
    radial-gradient(2px 2px at 40px 70px, rgba(255, 255, 255, 0.2), transparent),
    radial-gradient(1px 1px at 90px 40px, rgba(255, 255, 255, 0.4), transparent),
    radial-gradient(1px 1px at 130px 80px, rgba(255, 255, 255, 0.3), transparent),
    radial-gradient(2px 2px at 160px 30px, rgba(255, 255, 255, 0.2), transparent);
  background-size: 200px 200px;
  animation: twinkle 8s ease-in-out infinite;
  pointer-events: none;
}

@keyframes twinkle {
  0%, 100% { opacity: 0.5; }
  50% { opacity: 1; }
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -50px;
  left: 0;
  right: 0;
  height: 100px;
  background: linear-gradient(to top, var(--bg), transparent);
  pointer-events: none;
}

.hero-grid {
  display: flex;
  gap: 40px;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero h1 {
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
  text-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.hero .lead {
  font-size: clamp(1rem, 2.5vw, 1.2rem);
  max-width: 640px;
  opacity: 0.9;
  margin-bottom: 28px;
  border-left: 4px solid var(--accent2);
  padding-left: 20px;
  line-height: 1.8;
}

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

.hero svg {
  flex-shrink: 0;
  max-width: 100%;
  height: auto;
  animation: float 6s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-15px); }
}

/* ---------- 按钮 ---------- */
.btn {
  padding: 12px 28px;
  border-radius: 60px;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-slow);
  border: 1px solid transparent;
  cursor: pointer;
  font-size: 0.95rem;
  gap: 8px;
  letter-spacing: 0.02em;
}

.btn-primary {
  background: var(--btn-primary-bg);
  color: var(--btn-primary-text);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
}

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

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  transform: translateY(-3px);
}

/* ---------- 区块通用 ---------- */
.section {
  margin: 56px 0;
}

.section-title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 700;
  margin-bottom: 28px;
  border-left: 8px solid var(--accent2);
  padding-left: 16px;
  line-height: 1.3;
  position: relative;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 16px;
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--accent2), transparent);
  border-radius: 3px;
}

/* ---------- 卡片网格 ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}

/* 卡片样式 */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 28px;
  box-shadow: 0 4px 12px var(--shadow);
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent2), transparent);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: 0 12px 30px var(--card-hover-shadow);
  border-color: var(--accent2);
}

.card:hover::before {
  opacity: 1;
}

.card h3 {
  font-size: 1.15rem;
  margin-bottom: 10px;
  color: var(--text);
}

.card h4 {
  font-size: 1rem;
  margin-bottom: 8px;
}

.card p {
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.7;
}

/* ---------- 文章列表 ---------- */
.article-list {
  display: flex;
  flex-direction: column;
}

.article-item {
  display: flex;
  gap: 20px;
  padding: 20px 0;
  border-bottom: 1px solid var(--border);
  transition: background 0.2s ease, padding 0.2s ease;
  align-items: flex-start;
}

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

.article-item:hover {
  background: var(--badge-bg);
  padding-left: 10px;
  padding-right: 10px;
  border-radius: 12px;
}

.article-item svg {
  flex-shrink: 0;
  width: 64px;
  height: 64px;
  border-radius: 12px;
}

.article-item h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 6px;
  line-height: 1.4;
}

.article-meta {
  color: var(--muted);
  font-size: 0.85rem;
  margin-bottom: 8px;
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.article-item p:not(.article-meta) {
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.7;
  margin-bottom: 8px;
}

.article-item a {
  color: var(--accent2);
  font-weight: 500;
  font-size: 0.9rem;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.article-item a:hover {
  text-decoration: underline;
}

/* ---------- 统计数字 ---------- */
.stat {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--accent2);
  line-height: 1.2;
  display: inline-block;
}

/* ---------- FAQ ---------- */
.faq-item {
  border-bottom: 1px solid var(--border);
  padding: 18px 0;
  transition: background 0.2s ease;
}

.faq-item:first-child {
  border-top: 1px solid var(--border);
}

.faq-q {
  font-weight: 600;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  font-size: 1rem;
  transition: color 0.2s ease;
  user-select: none;
}

.faq-q:hover {
  color: var(--accent2);
}

.faq-q span {
  font-size: 1.4rem;
  font-weight: 400;
  color: var(--accent2);
  transition: transform 0.3s ease;
  flex-shrink: 0;
}

.faq-a {
  margin-top: 12px;
  color: var(--muted);
  display: none;
  font-size: 0.95rem;
  line-height: 1.8;
  padding-right: 20px;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-5px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ---------- HowTo 教程 ---------- */
#howto .card {
  padding: 32px;
  line-height: 1.8;
}

#howto .card p {
  margin-bottom: 12px;
}

#howto .card ol {
  margin-left: 24px;
  margin-bottom: 16px;
}

#howto .card li {
  margin-bottom: 8px;
}

#howto .card strong {
  color: var(--accent2);
}

/* ---------- 页脚 ---------- */
footer {
  background: var(--footer-bg);
  border-top: 1px solid var(--border);
  padding: 48px 0 24px;
  margin-top: 60px;
  transition: background 0.3s ease;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
}

.footer-grid h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 14px;
  color: var(--text);
}

.footer-grid p {
  color: var(--muted);
  font-size: 0.9rem;
  margin-bottom: 6px;
}

.footer-links a {
  display: block;
  margin: 6px 0;
  color: var(--muted);
  font-size: 0.9rem;
  transition: color 0.2s ease, padding-left 0.2s ease;
}

.footer-links a:hover {
  color: var(--accent2);
  padding-left: 4px;
}

.copyright {
  margin-top: 32px;
  text-align: center;
  color: var(--muted);
  font-size: 0.85rem;
  padding-top: 20px;
  border-top: 1px solid var(--border);
}

/* ---------- 返回顶部 ---------- */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  background: var(--accent2);
  color: white;
  border: none;
  border-radius: 50%;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
  z-index: 999;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
}

.back-to-top.show {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  transform: translateY(-4px) scale(1.05);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.4);
}

/* ---------- 滚动动画 ---------- */
.scroll-animation {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.scroll-animation.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- 响应式设计 ---------- */
@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }

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

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }

  .mobile-menu {
    display: flex;
  }

  .search-box input {
    width: 70px;
  }

  .search-box input:focus {
    width: 100px;
  }

  .hero {
    padding: 48px 0 40px;
  }

  .hero-grid {
    flex-direction: column;
    align-items: flex-start;
    gap: 32px;
  }

  .hero svg {
    width: 180px;
    height: auto;
  }

  .container {
    padding: 0 16px;
  }

  .section {
    margin: 40px 0;
  }

  .card {
    padding: 20px;
  }

  .article-item {
    flex-direction: column;
    gap: 12px;
  }

  .article-item svg {
    width: 48px;
    height: 48px;
  }

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

  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 44px;
    height: 44px;
  }
}

@media (max-width: 480px) {
  .nav-inner {
    gap: 8px;
  }

  .logo span {
    font-size: 1.1rem;
  }

  .search-box {
    padding: 6px 10px;
  }

  .search-box input {
    width: 50px;
  }

  .search-box input:focus {
    width: 80px;
  }

  .icon-btn {
    width: 36px;
    height: 36px;
  }

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

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

  .btn {
    padding: 10px 20px;
    font-size: 0.9rem;
  }

  .stat {
    font-size: 2rem;
  }

  .section-title {
    font-size: 1.3rem;
  }
}

/* ---------- 无障碍与辅助功能 ---------- */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* 焦点可见性 */
:focus-visible {
  outline: 2px solid var(--accent2);
  outline-offset: 2px;
}

/* 打印优化 */
@media print {
  .navbar,
  .hero,
  .back-to-top,
  .mobile-menu,
  .search-box,
  .icon-btn {
    display: none !important;
  }

  body {
    background: white;
    color: black;
  }

  .card {
    box-shadow: none;
    border: 1px solid #ddd;
  }
}

/* ---------- 自定义动画与增强 ---------- */

/* 卡片悬浮光效 */
.card::after {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle, rgba(88, 166, 255, 0.1) 0%, transparent 70%);
  opacity: 0;
  transition: opacity 0.4s ease;
  pointer-events: none;
}

.card:hover::after {
  opacity: 1;
}

/* 品牌区渐变文字 */
.brand-gradient-text {
  background: linear-gradient(135deg, var(--accent2), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* 毛玻璃卡片（特殊用途） */
.glass-card {
  background: var(--glass-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--glass-border);
  border-radius: 20px;
  padding: 24px;
}

/* 标签徽章 */
.badge {
  display: inline-block;
  padding: 4px 12px;
  background: var(--badge-bg);
  color: var(--badge-text);
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 500;
}

/* 分割线 */
.divider {
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border), transparent);
  margin: 24px 0;
  border: none;
}

/* 强调框 */
.callout {
  background: var(--badge-bg);
  border-left: 4px solid var(--accent2);
  padding: 16px 20px;
  border-radius: 0 12px 12px 0;
  margin: 20px 0;
  font-size: 0.95rem;
}

/* 暗色模式下的图片滤镜调整 */
[data-theme="dark"] img {
  filter: brightness(0.9) contrast(1.1);
}

/* 移动端菜单展开（预留） */
.mobile-nav-open .nav-links {
  display: flex;
  flex-direction: column;
  position: absolute;
  top: 64px;
  left: 0;
  right: 0;
  background: var(--bg2);
  padding: 16px;
  box-shadow: 0 8px 20px var(--shadow);
  border-bottom: 1px solid var(--border);
}

/* 滚动进度条（可选增强） */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent2), var(--accent));
  z-index: 1001;
  transition: width 0.1s ease;
}

/* 暗色模式过渡优化 */
body,
.navbar,
.card,
.footer,
.hero {
  transition: background 0.3s ease, color 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

/* 确保所有SVG图标在暗色模式下可见 */
[data-theme="dark"] svg {
  stroke: currentColor;
}

/* 高DIP显示优化 */
@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
  .card,
  .btn,
  .icon-btn {
    -webkit-font-smoothing: antialiased;
  }
}

/* 小屏设备触控优化 */
@media (max-width: 768px) {
  .btn,
  .icon-btn,
  .faq-q {
    min-height: 44px;
  }

  .nav-links a {
    padding: 12px 0;
  }
}

/* 确保内容区域不会过窄 */
@media (min-width: 1400px) {
  .container {
    max-width: 1400px;
  }
}

/* 暗色模式下的阴影调整 */
[data-theme="dark"] .card {
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

/* 渐变边框效果 */
.gradient-border {
  border: 1px solid transparent;
  background:
    linear-gradient(var(--card), var(--card)) padding-box,
    linear-gradient(135deg, var(--accent2), transparent) border-box;
}

/* 最终优化：确保所有交互元素都有合适的触控区域 */
button,
.btn,
a,
input {
  touch-action: manipulation;
}
```