@import url('https://fonts.googleapis.com/css2?family=Orbitron:wght@400;500;600;700;800;900&family=Rajdhani:wght@300;400;500;600;700&family=Noto+Sans+SC:wght@300;400;500;700&display=swap');

:root {
  --bg-primary: #f5f7fa;
  --bg-secondary: #eef1f6;
  --bg-card: #ffffff;
  --bg-elevated: #f1f3f7;
  --accent-cyan: #3b82f6;
  --accent-purple: #7c3aed;
  --accent-gradient: linear-gradient(135deg, #3b82f6 0%, #7c3aed 100%);
  --accent-gradient-hover: linear-gradient(135deg, #60a5fa 0%, #8b5cf6 100%);
  --text-primary: #1a1a2e;
  --text-secondary: #64748b;
  --text-muted: #94a3b8;
  --border-color: rgba(0, 0, 0, 0.08);
  --border-highlight: rgba(59, 130, 246, 0.4);
  --shadow-glow: 0 4px 20px rgba(59, 130, 246, 0.12);
  --shadow-card: 0 2px 12px rgba(0, 0, 0, 0.06);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --font-display: 'Orbitron', 'Noto Sans SC', sans-serif;
  --font-body: 'Rajdhani', 'Noto Sans SC', sans-serif;
  --font-cn: 'Noto Sans SC', sans-serif;
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  outline: none;
}

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

/* 通用按钮样式 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: all var(--transition-normal);
  letter-spacing: 0.5px;
}

.btn-primary {
  background: var(--accent-gradient);
  color: #fff;
  box-shadow: 0 4px 16px rgba(59, 130, 246, 0.25);
}

.btn-primary:hover {
  background: var(--accent-gradient-hover);
  box-shadow: 0 6px 24px rgba(59, 130, 246, 0.35);
  transform: translateY(-2px);
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  box-shadow: 0 1px 3px rgba(0,0,0,0.04);
}

.btn-secondary:hover {
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
  box-shadow: var(--shadow-glow);
}

.btn-outline {
  background: transparent;
  color: var(--accent-cyan);
  border: 1px solid var(--accent-cyan);
}

.btn-outline:hover {
  background: rgba(59, 130, 246, 0.08);
  box-shadow: var(--shadow-glow);
}

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

/* 文字渐变 */
.text-gradient {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* 发光边框 */
.glow-border {
  position: relative;
}
.glow-border::before {
  content: '';
  position: absolute;
  inset: -1px;
  border-radius: inherit;
  padding: 1px;
  background: var(--accent-gradient);
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  opacity: 0;
  transition: opacity var(--transition-normal);
  pointer-events: none;
}
.glow-border:hover::before {
  opacity: 1;
}

/* 滚动显示动画类 */
.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}
.reveal.active {
  opacity: 1;
  transform: translateY(0);
}

/* 语言切换下拉 */
.lang-switch {
  position: relative;
}
.lang-switch .lang-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-size: 13px;
  font-weight: 500;
  transition: all var(--transition-fast);
}
.lang-switch .lang-btn:hover {
  border-color: var(--accent-cyan);
  color: var(--text-primary);
}
.lang-switch .lang-dropdown {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  min-width: 140px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 6px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-8px);
  transition: all var(--transition-fast);
  z-index: 1000;
  box-shadow: 0 8px 24px rgba(0,0,0,0.1);
}
.lang-switch.open .lang-dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.lang-switch .lang-dropdown a {
  display: block;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}
.lang-switch .lang-dropdown a:hover,
.lang-switch .lang-dropdown a.active {
  background: rgba(59, 130, 246, 0.08);
  color: var(--accent-cyan);
}

/* 头部导航通用 */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 999;
  height: 72px;
  display: flex;
  align-items: center;
  transition: background var(--transition-normal), backdrop-filter var(--transition-normal);
}
.site-header.scrolled {
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
}
.site-header .header-inner {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.site-header .logo {
  font-family: var(--font-display);
  font-size: 24px;
  font-weight: 800;
  letter-spacing: 2px;
  color: var(--text-primary);
}
.site-header .logo span {
  color: var(--accent-cyan);
}
.site-header nav {
  display: flex;
  align-items: center;
  gap: 32px;
}
.site-header .nav-link {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  line-height: 72px;
  text-decoration: none;
  transition: color var(--transition-fast);
}
.site-header .nav-link:hover {
  color: var(--accent-cyan);
}

/* 页脚通用 */
.site-footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: 60px 0 30px;
}
.site-footer .footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}
.site-footer .footer-brand .logo {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 800;
  margin-bottom: 12px;
}
.site-footer .footer-brand p {
  color: var(--text-muted);
  font-size: 14px;
  line-height: 1.7;
}
.site-footer .footer-links h4 {
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--text-primary);
  text-transform: uppercase;
  letter-spacing: 1px;
}
.site-footer .footer-links ul {
  list-style: none;
}
.site-footer .footer-links li {
  margin-bottom: 10px;
}
.site-footer .footer-links a {
  color: var(--text-muted);
  font-size: 14px;
  transition: color var(--transition-fast);
}
.site-footer .footer-links a:hover {
  color: var(--accent-cyan);
}
.site-footer .footer-bottom {
  border-top: 1px solid var(--border-color);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--text-muted);
  font-size: 13px;
}

/* 移动端页脚适配 */
@media (max-width: 768px) {
  .site-footer .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px 24px;
  }
  .site-footer .footer-bottom {
    flex-direction: column;
    gap: 12px;
    text-align: center;
  }
}
@media (max-width: 480px) {
  .site-footer .footer-grid {
    grid-template-columns: 1fr;
  }
}