```css
/* ===== 天美传媒 · 全站样式表 ===== */
/* 版本：1.0 | 日期：2025-03-01 | 支持响应式+暗色模式 */

/* ---------- 设计变量 ---------- */
:root {
  --bg-primary: #f8fafc;
  --bg-card: #ffffff;
  --bg-soft: #eef2f6;
  --bg-glass: rgba(255, 255, 255, 0.72);
  --text-heading: #1e293b;
  --text-body: #2d3a4a;
  --text-secondary: #41566b;
  --text-muted: #526477;
  --accent: #1f3a5f;
  --accent-light: #2b4c7a;
  --accent-glow: rgba(43, 76, 122, 0.25);
  --border: #dce3ec;
  --border-light: rgba(220, 227, 236, 0.6);
  --footer-bg: #1e293b;
  --footer-text: #d1d9e6;
  --footer-heading: #ffffff;
  --footer-border: #2d3f58;
  --btn-text: #ffffff;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 6px 20px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.09);
  --shadow-glow: 0 0 0 1px rgba(43, 76, 122, 0.08), 0 8px 30px rgba(43, 76, 122, 0.12);
  --radius-sm: 10px;
  --radius-md: 18px;
  --radius-lg: 28px;
  --radius-pill: 50px;
  --transition-fast: 0.2s ease;
  --transition-base: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.6s cubic-bezier(0.16, 1, 0.3, 1);
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: "SF Mono", "Fira Code", "Roboto Mono", monospace;
}

/* 暗色主题变量覆盖 */
[data-theme="dark"] {
  --bg-primary: #0f172a;
  --bg-card: #1e293b;
  --bg-soft: #172032;
  --bg-glass: rgba(30, 41, 59, 0.72);
  --text-heading: #f1f5f9;
  --text-body: #e2e8f0;
  --text-secondary: #cbd5e1;
  --text-muted: #9fafc2;
  --accent: #3b6ea5;
  --accent-light: #5b8bc0;
  --accent-glow: rgba(91, 139, 192, 0.25);
  --border: #2d3f58;
  --border-light: rgba(45, 63, 88, 0.6);
  --footer-bg: #0b1220;
  --footer-text: #b6c2d6;
  --footer-heading: #ffffff;
  --footer-border: #24344d;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 6px 20px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.5);
  --shadow-glow: 0 0 0 1px rgba(91, 139, 192, 0.15), 0 8px 30px rgba(0, 0, 0, 0.5);
}

/* ---------- 基础重置 ---------- */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  scrollbar-width: thin;
  scrollbar-color: var(--accent) var(--bg-soft);
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-body);
  line-height: 1.7;
  font-size: 16px;
  overflow-x: hidden;
  transition: background-color 0.4s ease, color 0.4s ease;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* 滚动条 */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}
::-webkit-scrollbar-track {
  background: var(--bg-primary);
}
::-webkit-scrollbar-thumb {
  background: var(--accent-light);
  border-radius: 8px;
  transition: background 0.3s;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--accent);
}

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

/* 区块通用 */
.section {
  padding: 4rem 0;
  position: relative;
}

.section-title {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  color: var(--text-heading);
  margin-bottom: 2rem;
  border-left: 6px solid var(--accent);
  padding-left: 1.2rem;
  font-weight: 800;
  letter-spacing: -0.5px;
  line-height: 1.3;
  position: relative;
}

/* ---------- 滚动动画 ---------- */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.section,
.hero,
.navbar,
footer {
  animation: fadeUp 0.7s ease both;
}

.section:nth-of-type(2) { animation-delay: 0.05s; }
.section:nth-of-type(3) { animation-delay: 0.1s; }
.section:nth-of-type(4) { animation-delay: 0.15s; }
.section:nth-of-type(5) { animation-delay: 0.2s; }

/* ---------- 渐变文字效果 ---------- */
.logo a,
.hero h1 {
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-light) 60%, #7aa5c9 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ---------- 导航栏 ---------- */
.navbar {
  background: var(--bg-glass);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  padding: 0.8rem 0;
  position: sticky;
  top: 0;
  z-index: 1000;
  border-bottom: 1px solid var(--border-light);
  transition: box-shadow 0.3s ease, background-color 0.4s ease;
}

.navbar:hover {
  box-shadow: var(--shadow-sm);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.logo a {
  font-size: clamp(1.4rem, 2.5vw, 1.8rem);
  font-weight: 800;
  text-decoration: none;
  letter-spacing: -0.5px;
  transition: transform 0.2s ease;
  display: inline-block;
}

.logo a:hover {
  transform: scale(1.02);
}

.nav-links {
  display: flex;
  gap: clamp(1rem, 2vw, 2rem);
  align-items: center;
  list-style: none;
}

.nav-links a {
  color: var(--text-body);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.95rem;
  transition: color 0.25s ease, border-color 0.25s ease;
  padding: 0.3rem 0.2rem;
  border-bottom: 2px solid transparent;
}

.nav-links a:hover {
  color: var(--accent-light);
  border-bottom-color: var(--accent-light);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

/* 搜索框 */
.search-box {
  display: flex;
  align-items: center;
  background: var(--bg-soft);
  border-radius: var(--radius-pill);
  padding: 0.2rem 0.2rem 0.2rem 1.2rem;
  border: 1px solid var(--border-light);
  transition: box-shadow 0.3s ease, border-color 0.3s ease;
}

.search-box:focus-within {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-glow);
}

.search-box input {
  border: none;
  background: transparent;
  color: var(--text-body);
  padding: 0.4rem 0.3rem;
  width: clamp(100px, 12vw, 170px);
  outline: none;
  font-size: 0.9rem;
  font-family: inherit;
}

.search-box input::placeholder {
  color: var(--text-muted);
  opacity: 0.8;
}

.search-box button {
  background: var(--accent);
  border: none;
  border-radius: var(--radius-pill);
  padding: 0.45rem 1rem;
  color: var(--btn-text);
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  transition: background-color 0.3s ease, transform 0.2s ease;
  flex-shrink: 0;
}

.search-box button:hover {
  background: var(--accent-light);
  transform: scale(1.03);
}

/* 主题切换 & 菜单按钮 */
.theme-toggle,
.menu-toggle {
  background: var(--bg-soft);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-pill);
  width: 40px;
  height: 40px;
  font-size: 1.2rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-heading);
  transition: background-color 0.3s ease, transform 0.2s ease, box-shadow 0.3s ease;
  flex-shrink: 0;
}

.theme-toggle:hover,
.menu-toggle:hover {
  background: var(--accent);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}

.menu-toggle {
  display: none;
}

/* 移动端导航 */
.mobile-nav {
  display: none;
  flex-direction: column;
  background: var(--bg-card);
  padding: 0.8rem 1.2rem;
  border-top: 1px solid var(--border);
  border-radius: 0 0 var(--radius-md) var(--radius-md);
  box-shadow: var(--shadow-md);
}

.mobile-nav a {
  padding: 0.8rem 0.4rem;
  color: var(--text-body);
  text-decoration: none;
  font-weight: 500;
  border-bottom: 1px solid var(--border-light);
  transition: color 0.2s ease, padding-left 0.2s ease;
}

.mobile-nav a:last-child {
  border-bottom: none;
}

.mobile-nav a:hover {
  color: var(--accent-light);
  padding-left: 0.8rem;
}

.mobile-nav.active {
  display: flex;
}

/* 响应式导航 */
@media (max-width: 800px) {
  .nav-links,
  .search-box {
    display: none;
  }
  .menu-toggle {
    display: flex;
  }
  .navbar .container {
    justify-content: space-between;
  }
}

/* ---------- Hero Banner ---------- */
.hero {
  background: linear-gradient(120deg, var(--bg-card) 0%, var(--bg-soft) 50%, var(--bg-card) 100%);
  padding: clamp(2.5rem, 6vw, 5rem) 0;
  border-bottom: 1px solid var(--border);
  position: relative;
  overflow: hidden;
}

/* 背景装饰光斑 */
.hero::before {
  content: '';
  position: absolute;
  top: -30%;
  right: -10%;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, var(--accent-glow) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

.hero .container {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 2.5rem;
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero h1 {
  font-size: clamp(1.9rem, 4.5vw, 3.2rem);
  font-weight: 800;
  line-height: 1.2;
  color: var(--text-heading);
  letter-spacing: -1px;
  margin-bottom: 1.2rem;
}

.hero p {
  font-size: clamp(1rem, 1.8vw, 1.2rem);
  color: var(--text-body);
  margin-bottom: 2rem;
  max-width: 92%;
  line-height: 1.8;
}

.hero svg {
  width: 100%;
  max-width: 460px;
  height: auto;
  margin-left: auto;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  transition: transform 0.4s ease;
}

.hero svg:hover {
  transform: scale(1.02);
}

.btn-group {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

/* 按钮 */
.btn {
  background: var(--accent);
  color: var(--btn-text);
  padding: 0.8rem 2.2rem;
  border-radius: var(--radius-pill);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.98rem;
  transition: background-color 0.3s ease, transform 0.2s ease, box-shadow 0.3s ease;
  border: none;
  display: inline-block;
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(31, 58, 95, 0.2);
}

.btn:hover {
  background: var(--accent-light);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px var(--accent-glow);
}

.btn:active {
  transform: translateY(0);
}

.btn-outline {
  background: transparent;
  border: 2px solid var(--accent);
  color: var(--accent);
  padding: 0.75rem 2.1rem;
  border-radius: var(--radius-pill);
  font-weight: 600;
  font-size: 0.98rem;
  text-decoration: none;
  transition: all 0.3s ease;
  display: inline-block;
}

.btn-outline:hover {
  background: var(--accent);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 4px 16px var(--accent-glow);
}

.btn-small {
  background: var(--accent-light);
  color: #fff;
  padding: 0.4rem 1.2rem;
  border-radius: var(--radius-pill);
  font-size: 0.85rem;
  text-decoration: none;
  display: inline-block;
  margin-top: 0.8rem;
  transition: background-color 0.3s ease, transform 0.2s ease;
  border: none;
  cursor: pointer;
}

.btn-small:hover {
  background: var(--accent);
  transform: translateX(4px);
}

/* ---------- 卡片基础 ---------- */
.card {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 2rem 1.8rem;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
  transition: transform 0.35s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.35s 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(--accent), var(--accent-light), transparent);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-glow);
  border-color: var(--accent-light);
}

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

.card h3 {
  color: var(--text-heading);
  margin-bottom: 0.8rem;
  font-size: 1.4rem;
  font-weight: 700;
  letter-spacing: -0.3px;
}

.card p {
  color: var(--text-body);
  line-height: 1.8;
}

.card ul {
  color: var(--text-body);
}

.card strong {
  color: var(--text-heading);
}

/* 徽标 */
.badge {
  background: var(--bg-soft);
  color: var(--accent);
  padding: 0.3rem 1.2rem;
  border-radius: var(--radius-pill);
  font-size: 0.85rem;
  font-weight: 600;
  display: inline-block;
  margin-bottom: 1rem;
  border: 1px solid var(--border-light);
  letter-spacing: 0.02em;
}

/* ---------- 网格布局 ---------- */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

/* 响应式网格 */
@media (max-width: 1024px) {
  .grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .grid-2,
  .grid-3 {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
  .section {
    padding: 3rem 0;
  }
  .section-title {
    font-size: 1.6rem;
  }
}

/* ---------- 文章列表 ---------- */
.article-list {
  display: flex;
  flex-direction: column;
  gap: 1.4rem;
}

.article-item {
  background: var(--bg-card);
  padding: 1.8rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
}

.article-item:hover {
  border-color: var(--accent-light);
  box-shadow: var(--shadow-md);
  transform: translateX(8px);
}

.article-item h4 {
  color: var(--text-heading);
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
  font-weight: 700;
  transition: color 0.3s ease;
}

.article-item:hover h4 {
  color: var(--accent-light);
}

.article-meta {
  color: var(--text-muted);
  font-size: 0.88rem;
  margin-bottom: 0.6rem;
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.article-meta::before {
  content: '📅';
  font-size: 0.9rem;
}

.article-summary {
  color: var(--text-body);
  line-height: 1.7;
  margin-bottom: 0.4rem;
}

/* ---------- FAQ ---------- */
.faq-item {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  margin-bottom: 1rem;
  border: 1px solid var(--border);
  overflow: hidden;
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.faq-item:hover {
  border-color: var(--accent-light);
  box-shadow: var(--shadow-sm);
}

.faq-question {
  padding: 1.2rem 1.8rem;
  font-weight: 600;
  color: var(--text-heading);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 1rem;
  transition: background-color 0.3s ease;
  user-select: none;
}

.faq-question:hover {
  background: var(--bg-soft);
}

.faq-answer {
  padding: 0 1.8rem 1.5rem;
  color: var(--text-body);
  display: none;
  line-height: 1.8;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-8px); }
  to { opacity: 1; transform: translateY(0); }
}

.faq-item.active .faq-answer {
  display: block;
}

.faq-item.active .faq-question::after {
  content: "−";
  color: var(--accent);
}

.faq-question::after {
  content: "+";
  font-size: 1.5rem;
  color: var(--accent);
  font-weight: 300;
  transition: transform 0.3s ease;
}

.faq-item.active .faq-question::after {
  transform: rotate(180deg);
}

/* ---------- 页脚 ---------- */
footer {
  background: var(--footer-bg);
  color: var(--footer-text);
  padding: 3.5rem 0 1.5rem;
  margin-top: 3rem;
  position: relative;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2.5rem;
  margin-bottom: 2rem;
}

.footer-grid h4 {
  color: var(--footer-heading);
  margin-bottom: 1.2rem;
  font-size: 1.1rem;
  font-weight: 700;
  position: relative;
}

.footer-grid h4::after {
  content: '';
  display: block;
  width: 30px;
  height: 2px;
  background: var(--accent);
  margin-top: 0.4rem;
}

.footer-grid a {
  color: var(--footer-text);
  text-decoration: none;
  display: block;
  margin-bottom: 0.7rem;
  font-size: 0.92rem;
  transition: color 0.3s ease, padding-left 0.2s ease;
}

.footer-grid a:hover {
  color: var(--footer-heading);
  padding-left: 6px;
}

.copyright {
  border-top: 1px solid var(--footer-border);
  padding-top: 1.5rem;
  margin-top: 2rem;
  text-align: center;
  color: var(--footer-text);
  font-size: 0.88rem;
}

.copyright p {
  color: var(--footer-text);
}

/* 响应式页脚 */
@media (max-width: 900px) {
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
  }
}

@media (max-width: 540px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 1.8rem;
  }
  footer {
    padding: 2.5rem 0 1rem;
  }
}

/* ---------- 返回顶部按钮 ---------- */
.back-top {
  position: fixed;
  bottom: 2.5rem;
  right: 2rem;
  background: var(--accent);
  color: white;
  border: none;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  font-size: 1.6rem;
  cursor: pointer;
  z-index: 1000;
  box-shadow: var(--shadow-md);
  transition: all 0.3s ease;
  display: none;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border-light);
}

.back-top:hover {
  background: var(--accent-light);
  transform: translateY(-4px) scale(1.05);
  box-shadow: var(--shadow-lg);
}

.back-top:active {
  transform: translateY(0) scale(0.95);
}

/* ---------- 工具类 ---------- */
.text-muted {
  color: var(--text-muted);
}

.mt-2 {
  margin-top: 1rem;
}

.mt-3 {
  margin-top: 2rem;
}

/* SVG 文字适配 */
svg text {
  fill: var(--text-heading);
  font-weight: 600;
}

.svg-text {
  fill: var(--text-heading);
}

/* 图片占位样式 */
.img-placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  color: var(--text-secondary);
  background: var(--bg-soft);
  border-radius: var(--radius-md);
  min-height: 200px;
}

/* ---------- 联系区块卡片微调 ---------- */
#contact .card p {
  margin-bottom: 0.8rem;
  line-height: 1.8;
}

#contact .card strong {
  color: var(--accent);
  font-weight: 700;
}

/* ---------- HowTo 教程卡片 ---------- */
#howto .card h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
}

#howto .card p {
  margin-bottom: 0.8rem;
}

/* ---------- 响应式 Hero ---------- */
@media (max-width: 900px) {
  .hero .container {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 2rem;
  }
  .hero p {
    max-width: 100%;
    margin-left: auto;
    margin-right: auto;
  }
  .hero svg {
    margin: 0 auto;
    max-width: 340px;
  }
  .btn-group {
    justify-content: center;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 1.8rem;
  }
  .hero p {
    font-size: 1rem;
  }
  .btn,
  .btn-outline {
    padding: 0.7rem 1.6rem;
    font-size: 0.9rem;
    width: 100%;
    text-align: center;
  }
  .btn-group {
    flex-direction: column;
    width: 100%;
    gap: 0.8rem;
  }
  .container {
    padding: 0 16px;
  }
  .card {
    padding: 1.5rem 1.2rem;
  }
  .article-item {
    padding: 1.2rem;
  }
  .faq-question {
    padding: 1rem 1rem;
    font-size: 0.95rem;
  }
  .faq-answer {
    padding: 0 1rem 1.2rem;
  }
}

/* ---------- 暗色模式专项调整 ---------- */
[data-theme="dark"] .logo a,
[data-theme="dark"] .hero h1 {
  background: linear-gradient(135deg, var(--accent-light) 0%, #7aa5c9 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

[data-theme="dark"] .btn {
  color: #fff;
}

[data-theme="dark"] .btn-outline {
  color: var(--accent-light);
  border-color: var(--accent-light);
}

[data-theme="dark"] .btn-outline:hover {
  background: var(--accent-light);
  color: #fff;
}

[data-theme="dark"] .search-box button {
  color: #fff;
}

/* ---------- 减少动画偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* ---------- 打印样式 ---------- */
@media print {
  .navbar,
  .back-top,
  .footer-grid,
  .btn-group,
  .search-box {
    display: none !important;
  }
  body {
    background: #fff;
    color: #000;
  }
  .container {
    max-width: 100%;
    padding: 0;
  }
  .section {
    padding: 1.5rem 0;
  }
  .card {
    box-shadow: none;
    border: 1px solid #ddd;
  }
}
```