/* ===== 天美传媒 全站样式表 ===== */
/* ===== 设计系统与主题变量 ===== */
:root {
  --bg: #f8fafc;
  --surface: #ffffff;
  --surface2: #eef2f6;
  --surface3: #e2e8f0;
  --text-primary: #1a2b3c;
  --text-secondary: #2c3e50;
  --text-muted: #3e5569;
  --text-heading: #0b1a2e;
  --brand: #0057b3;
  --brand-dark: #003d80;
  --brand-light: #3b82f6;
  --accent: #eab308;
  --accent-dark: #ca8a04;
  --link: #0057b3;
  --border: #cbd5e1;
  --footer-bg: #0b1a2e;
  --footer-text: #e2e8f0;
  --shadow: 0 4px 12px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 30px rgba(0,0,0,0.1);
  --header-bg: rgba(255,255,255,0.96);
  --dark-bg: #0f172a;
  --dark-surface: #1e293b;
  --dark-text: #e2e8f0;
  --dark-heading: #f8fafc;
  --dark-border: #334155;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
}

[data-theme="dark"] {
  --bg: #0b1220;
  --surface: #1a2332;
  --surface2: #1e2a3a;
  --surface3: #273548;
  --text-primary: #e2e8f0;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  --text-heading: #f1f5f9;
  --brand: #3b82f6;
  --brand-dark: #2563eb;
  --brand-light: #60a5fa;
  --accent: #fbbf24;
  --accent-dark: #f59e0b;
  --link: #93c5fd;
  --border: #334155;
  --footer-bg: #0b1220;
  --footer-text: #e2e8f0;
  --shadow: 0 4px 12px rgba(0,0,0,0.6);
  --shadow-lg: 0 10px 30px rgba(0,0,0,0.8);
  --header-bg: rgba(15,23,42,0.96);
}

/* ===== 全局重置与基础 ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  background: var(--bg);
  color: var(--text-primary);
  font-family: var(--font-sans);
  line-height: 1.75;
  transition: background 0.3s ease, color 0.3s ease;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  color: var(--text-heading);
  line-height: 1.3;
  font-weight: 600;
  letter-spacing: -0.02em;
}

p, li, span, div {
  color: var(--text-primary);
}

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

a:hover {
  text-decoration: underline;
  color: var(--brand-dark);
}

img, svg {
  max-width: 100%;
  display: inline-block;
}

::selection {
  background: rgba(0, 87, 179, 0.2);
  color: var(--text-heading);
}

/* ===== 滚动条美化 ===== */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

::-webkit-scrollbar-track {
  background: var(--surface2);
}

::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 5px;
}

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

/* ===== 容器 ===== */
.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 20px;
  width: 100%;
}

/* ===== 头部导航 ===== */
.site-header {
  background: var(--header-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid var(--border);
  box-shadow: 0 2px 20px rgba(0,0,0,0.04);
  transition: all 0.3s ease;
}

.site-header.scrolled {
  box-shadow: 0 4px 30px rgba(0,0,0,0.08);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  padding: 12px 0;
  gap: 10px;
}

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

.logo-icon {
  width: 40px;
  height: 40px;
  transition: transform 0.3s ease;
}

.logo-area:hover .logo-icon {
  transform: rotate(-5deg) scale(1.05);
}

.logo-text {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-heading);
  letter-spacing: 1px;
  background: linear-gradient(135deg, var(--brand), var(--brand-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.site-nav ul {
  display: flex;
  list-style: none;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.site-nav a {
  color: var(--text-secondary);
  font-weight: 500;
  position: relative;
  padding: 4px 2px;
  transition: color 0.2s ease;
}

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

.site-nav a:hover {
  color: var(--brand);
  text-decoration: none;
}

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

.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.search-box {
  display: flex;
  align-items: center;
  background: var(--surface2);
  border-radius: 30px;
  padding: 4px 4px 4px 14px;
  border: 1px solid var(--border);
  transition: all 0.3s ease;
  position: relative;
}

.search-box:focus-within {
  border-color: var(--brand);
  box-shadow: 0 0 0 3px rgba(0, 87, 179, 0.15);
  background: var(--surface);
}

.search-box input {
  background: transparent;
  border: none;
  outline: none;
  color: var(--text-primary);
  padding: 6px 8px;
  width: 130px;
  font-size: 0.9rem;
  transition: width 0.3s ease;
}

.search-box input:focus {
  width: 160px;
}

.search-box button {
  background: var(--brand);
  color: white;
  border: none;
  border-radius: 30px;
  padding: 6px 14px;
  cursor: pointer;
  font-weight: 500;
  font-size: 0.85rem;
  transition: all 0.3s ease;
  white-space: nowrap;
}

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

.icon-btn {
  background: none;
  border: 1px solid var(--border);
  border-radius: 30px;
  padding: 6px 12px;
  cursor: pointer;
  color: var(--text-primary);
  font-weight: 500;
  font-size: 0.95rem;
  transition: all 0.3s ease;
  display: flex;
  align-items: center;
  gap: 4px;
}

.icon-btn:hover {
  background: var(--surface2);
  border-color: var(--brand);
  transform: translateY(-1px);
}

.menu-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.8rem;
  color: var(--text-heading);
  cursor: pointer;
  line-height: 1;
  padding: 0 4px;
}

/* ===== Banner / Hero ===== */
.hero {
  background: linear-gradient(145deg, #0b1a2e 0%, #1a2b3c 50%, #0f2540 100%);
  color: white;
  padding: 60px 0;
  border-radius: 0 0 30px 30px;
  margin-bottom: 40px;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(59, 130, 246, 0.2) 0%, transparent 70%);
  animation: float 8s ease-in-out infinite;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(234, 179, 8, 0.15) 0%, transparent 70%);
  animation: float 6s ease-in-out infinite reverse;
}

@keyframes float {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(2deg); }
}

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

.hero-text {
  flex: 1 1 350px;
  animation: fadeInUp 0.8s ease;
}

.hero-text h1 {
  font-size: 2.8rem;
  color: white;
  margin-bottom: 16px;
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.2;
  text-shadow: 0 2px 20px rgba(0,0,0,0.3);
}

.hero-text p {
  color: #dce6f0;
  font-size: 1.2rem;
  margin-bottom: 24px;
  max-width: 600px;
}

.hero-btn {
  background: linear-gradient(135deg, var(--accent), var(--accent-dark));
  color: #0b1a2e;
  padding: 12px 32px;
  border-radius: 40px;
  font-weight: 600;
  display: inline-block;
  transition: all 0.3s ease;
  box-shadow: 0 4px 15px rgba(234, 179, 8, 0.3);
  border: none;
  cursor: pointer;
  font-size: 1rem;
}

.hero-btn:hover {
  transform: translateY(-3px) scale(1.02);
  box-shadow: 0 8px 25px rgba(234, 179, 8, 0.4);
  text-decoration: none;
  color: #0b1a2e;
}

.hero-slider {
  flex: 0 0 420px;
  background: rgba(255,255,255,0.08);
  padding: 24px;
  border-radius: 20px;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(255,255,255,0.1);
  animation: fadeInUp 0.8s ease 0.2s both;
}

.slide-item {
  padding: 12px 0;
  border-bottom: 1px solid rgba(255,255,255,0.1);
  transition: transform 0.3s ease;
}

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

.slide-item:hover {
  transform: translateX(8px);
}

.slide-item h3 {
  color: white;
  margin-bottom: 8px;
  font-size: 1.15rem;
  display: flex;
  align-items: center;
  gap: 8px;
}

.slide-item p {
  color: #e2e8f0;
  font-size: 0.95rem;
  opacity: 0.9;
}

/* ===== 区块标题 ===== */
.section-title {
  font-size: 2.1rem;
  margin: 40px 0 24px;
  border-left: 6px solid var(--brand);
  padding-left: 18px;
  position: relative;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -6px;
  left: 18px;
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), transparent);
  border-radius: 3px;
}

/* ===== 卡片网格与卡片 ===== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 24px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow);
  transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--brand), var(--accent));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s ease;
}

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

.card:hover::before {
  transform: scaleX(1);
}

.card h3 {
  margin-bottom: 12px;
  font-size: 1.2rem;
  font-weight: 600;
}

.card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}

.card .meta {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ===== 网格布局 ===== */
.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 25px;
}

.grid-2 > div {
  background: var(--surface);
  padding: 24px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  transition: all 0.3s ease;
  box-shadow: var(--shadow);
}

.grid-2 > div:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--brand-light);
}

.grid-2 h3, .grid-2 h4 {
  margin-bottom: 12px;
}

.grid-2 p {
  margin-bottom: 10px;
}

/* ===== 文章列表 ===== */
.article-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.article-item {
  background: var(--surface);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  border: 1px solid var(--border);
  transition: all 0.3s ease;
  box-shadow: var(--shadow);
  animation: fadeInUp 0.5s ease;
  animation-fill-mode: both;
}

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

.article-item h3 {
  margin-bottom: 8px;
  font-size: 1.1rem;
  transition: color 0.2s ease;
}

.article-item:hover h3 {
  color: var(--brand);
}

.article-meta {
  display: flex;
  gap: 20px;
  color: var(--text-muted);
  font-size: 0.85rem;
  margin-bottom: 8px;
}

.article-meta span {
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 4px;
}

.article-item p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}

.article-item a {
  font-weight: 500;
  margin-left: 4px;
  white-space: nowrap;
}

/* ===== FAQ手风琴 ===== */
.faq-item {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
  overflow: hidden;
  transition: all 0.3s ease;
  box-shadow: var(--shadow);
  animation: fadeInUp 0.5s ease;
  animation-fill-mode: both;
}

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

.faq-question {
  padding: 18px 24px;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--text-heading);
  font-size: 1.05rem;
  transition: background 0.3s ease;
  user-select: none;
}

.faq-question:hover {
  background: var(--surface2);
}

.faq-question span {
  font-size: 1.4rem;
  transition: transform 0.3s ease;
  color: var(--brand);
  font-weight: 400;
  line-height: 1;
}

.faq-item.active .faq-question span {
  transform: rotate(45deg);
}

.faq-answer {
  padding: 0 24px 20px;
  color: var(--text-primary);
  line-height: 1.8;
  font-size: 0.95rem;
  animation: slideDown 0.3s ease;
}

/* ===== 页脚 ===== */
.site-footer {
  background: var(--footer-bg);
  color: var(--footer-text);
  margin-top: 60px;
  padding: 50px 0 30px;
  position: relative;
  overflow: hidden;
}

.site-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--brand), var(--accent), var(--brand));
  background-size: 200% 100%;
  animation: gradientFlow 3s linear infinite;
}

@keyframes gradientFlow {
  0% { background-position: 0% 50%; }
  100% { background-position: 200% 50%; }
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 30px;
  margin-bottom: 30px;
}

.site-footer h4 {
  color: white;
  margin-bottom: 16px;
  font-size: 1.1rem;
  font-weight: 600;
}

.site-footer a {
  color: #cbd5e1;
  transition: all 0.3s ease;
  display: inline-block;
  margin: 4px 0;
}

.site-footer a:hover {
  color: white;
  transform: translateX(4px);
  text-decoration: none;
}

.footer-bottom {
  border-top: 1px solid #1e293b;
  margin-top: 30px;
  padding-top: 20px;
  font-size: 0.9rem;
  color: #94a3b8;
  text-align: center;
}

/* ===== 工具类 ===== */
.toc {
  background: var(--surface2);
  padding: 18px 24px;
  border-radius: var(--radius-md);
  margin: 24px 0;
  border-left: 4px solid var(--brand);
}

.breadcrumb {
  display: flex;
  gap: 8px;
  font-size: 0.9rem;
  margin: 16px 0;
  color: var(--text-secondary);
  flex-wrap: wrap;
  align-items: center;
}

.breadcrumb span {
  color: var(--text-secondary);
}

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

.btn {
  background: var(--brand);
  color: white;
  padding: 10px 20px;
  border-radius: 30px;
  border: none;
  cursor: pointer;
  font-weight: 500;
  transition: all 0.3s ease;
  display: inline-block;
  font-size: 0.95rem;
}

.btn:hover {
  background: var(--brand-dark);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 87, 179, 0.3);
  text-decoration: none;
  color: white;
}

.btn-outline {
  background: transparent;
  border: 2px solid var(--brand);
  color: var(--brand);
}

.btn-outline:hover {
  background: var(--brand);
  color: white;
}

.howto-step, .step {
  margin: 10px 0;
  padding-left: 12px;
  padding: 10px 16px;
  background: var(--surface2);
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--brand);
  font-size: 0.95rem;
  transition: all 0.3s ease;
}

.howto-step:hover, .step:hover {
  background: var(--surface3);
  transform: translateX(4px);
}

/* ===== 统计数字 ===== */
.stat-number {
  font-weight: 700;
  font-size: 2.2rem;
  color: var(--brand);
  line-height: 1.2;
  background: linear-gradient(135deg, var(--brand), var(--brand-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ===== 返回顶部 ===== */
#topBtn {
  position: fixed;
  bottom: 30px;
  right: 30px;
  background: linear-gradient(135deg, var(--brand), var(--brand-dark));
  color: white;
  border: none;
  border-radius: 50%;
  width: 48px;
  height: 48px;
  font-size: 1.4rem;
  cursor: pointer;
  display: none;
  z-index: 200;
  box-shadow: 0 4px 20px rgba(0, 87, 179, 0.4);
  transition: all 0.3s ease;
  line-height: 1;
}

#topBtn:hover {
  transform: translateY(-4px) scale(1.05);
  box-shadow: 0 8px 25px rgba(0, 87, 179, 0.5);
}

/* ===== 隐藏元素 ===== */
.schema-json {
  display: none;
}

/* ===== 动画关键帧 ===== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.05); }
}

/* ===== 滚动进入动画 ===== */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* 为各区块添加交错动画延迟 */
section:nth-child(1) .card { animation-delay: 0.1s; }
section:nth-child(2) .card { animation-delay: 0.2s; }
section:nth-child(3) .card { animation-delay: 0.3s; }
section:nth-child(4) .card { animation-delay: 0.4s; }

/* ===== 响应式设计 ===== */
/* 平板 */
@media (max-width: 1024px) {
  .hero-text h1 {
    font-size: 2.2rem;
  }
  
  .hero-slider {
    flex: 1 1 100%;
  }
  
  .section-title {
    font-size: 1.8rem;
  }
  
  .card-grid {
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 18px;
  }
}

/* 手机 */
@media (max-width: 768px) {
  .site-nav {
    display: none;
    width: 100%;
    order: 3;
    background: var(--surface);
    border-radius: var(--radius-md);
    padding: 16px;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border);
    margin-top: 10px;
  }
  
  .site-nav.open {
    display: block;
    animation: slideDown 0.3s ease;
  }
  
  .site-nav ul {
    flex-direction: column;
    gap: 4px;
  }
  
  .site-nav li {
    width: 100%;
  }
  
  .site-nav a {
    display: block;
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    transition: background 0.2s ease;
  }
  
  .site-nav a:hover {
    background: var(--surface2);
  }
  
  .site-nav a::after {
    display: none;
  }
  
  .menu-toggle {
    display: block;
  }
  
  .hero {
    padding: 40px 0;
    border-radius: 0 0 20px 20px;
  }
  
  .hero-content {
    flex-direction: column;
    gap: 24px;
  }
  
  .hero-text h1 {
    font-size: 1.8rem;
  }
  
  .hero-text p {
    font-size: 1rem;
  }
  
  .hero-slider {
    flex: 1 1 auto;
    width: 100%;
    padding: 16px;
  }
  
  .grid-2 {
    grid-template-columns: 1fr;
    gap: 16px;
  }
  
  .section-title {
    font-size: 1.5rem;
    margin: 30px 0 18px;
  }
  
  .card-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }
  
  .header-inner {
    padding: 10px 0;
    gap: 8px;
  }
  
  .search-box input {
    width: 90px;
  }
  
  .search-box input:focus {
    width: 110px;
  }
  
  .logo-text {
    font-size: 1.2rem;
  }
  
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 20px;
  }
  
  #topBtn {
    bottom: 20px;
    right: 20px;
    width: 42px;
    height: 42px;
    font-size: 1.2rem;
  }
}

/* 超小屏 */
@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }
  
  .header-actions {
    gap: 6px;
  }
  
  .search-box input {
    width: 70px;
  }
  
  .search-box input:focus {
    width: 90px;
  }
  
  .search-box button {
    padding: 5px 10px;
    font-size: 0.8rem;
  }
  
  .icon-btn {
    padding: 5px 8px;
    font-size: 0.85rem;
  }
  
  .hero-text h1 {
    font-size: 1.5rem;
  }
  
  .section-title {
    font-size: 1.3rem;
  }
  
  .article-item {
    padding: 16px;
  }
  
  .article-meta {
    flex-direction: column;
    gap: 4px;
  }
  
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }
  
  .faq-question {
    padding: 14px 16px;
    font-size: 0.95rem;
  }
  
  .faq-answer {
    padding: 0 16px 16px;
  }
}

/* ===== 打印样式 ===== */
@media print {
  .site-header,
  .hero,
  #topBtn,
  .site-footer,
  .breadcrumb {
    display: none !important;
  }
  
  body {
    background: white;
    color: black;
  }
  
  .container {
    max-width: 100%;
    padding: 0;
  }
}

/* ===== 无障碍辅助 ===== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    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: 3px solid var(--brand);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ===== 高对比度模式 ===== */
@media (prefers-contrast: high) {
  :root {
    --border: #000000;
    --text-muted: #1a1a1a;
  }
  
  [data-theme="dark"] {
    --border: #ffffff;
    --text-muted: #e2e8f0;
  }
}