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

/* --- 设计系统变量定义 --- */
:root {
  /* 调色盘 */
  --bg-dark: hsl(230, 25%, 8%);
  --bg-dark-card: hsla(230, 25%, 12%, 0.45);
  --bg-dark-card-hover: hsla(230, 25%, 15%, 0.6);
  --border-color: hsla(0, 0%, 100%, 0.08);
  --border-color-hover: hsla(190, 100%, 50%, 0.3);
  
  --primary: hsl(190, 100%, 50%);       /* 霓虹蓝/青 */
  --primary-rgb: 0, 242, 254;
  --secondary: hsl(280, 100%, 65%);     /* 霓虹紫/粉 */
  --secondary-rgb: 211, 76, 255;
  
  --gradient-primary: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  --gradient-dark: linear-gradient(180deg, hsl(230, 25%, 6%) 0%, hsl(230, 25%, 10%) 100%);
  --gradient-glow: radial-gradient(circle, hsla(190, 100%, 50%, 0.15) 0%, transparent 70%);

  /* 文字颜色 */
  --text-white: hsla(0, 0%, 100%, 0.95);
  --text-gray: hsla(0, 0%, 100%, 0.7);
  --text-muted: hsla(0, 0%, 100%, 0.4);

  /* 字体族 */
  --font-sans: 'Outfit', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

  /* 间距与过渡 */
  --nav-height: 80px;
  --transition-fast: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.7s cubic-bezier(0.4, 0, 0.2, 1);

  /* 毛玻璃与投影 */
  --glass-blur: blur(16px);
  --shadow-sm: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 25px -5px rgba(0, 0, 0, 0.3), 0 8px 10px -6px rgba(0, 0, 0, 0.3);
  --shadow-glow: 0 0 20px hsla(190, 100%, 50%, 0.2);
}

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

html, body {
  overflow-x: hidden;
  width: 100%;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-height);
  background-color: var(--bg-dark);
  font-family: var(--font-sans);
  color: var(--text-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  line-height: 1.6;
}

a {
  text-decoration: none;
  color: inherit;
  transition: var(--transition-fast);
}

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

ul {
  list-style: none;
}

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

/* --- 全局布局组件 --- */
.container {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 2rem;
}

.section {
  padding: 8rem 0;
  position: relative;
}

.section-bg-glow {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, hsla(190, 100%, 50%, 0.08) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

/* --- 头部导航栏 (Glassmorphism) --- */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--nav-height);
  z-index: 1000;
  border-bottom: 1px solid var(--border-color);
  background: hsla(230, 25%, 8%, 0.6);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  transition: var(--transition-normal);
}

.header.scrolled {
  height: 70px;
  background: hsla(230, 25%, 6%, 0.85);
  box-shadow: var(--shadow-lg);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 100%;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: 1px;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.logo-dot {
  width: 12px;
  height: 12px;
  background: var(--primary);
  border-radius: 50%;
  box-shadow: 0 0 10px var(--primary);
  animation: logoGlow 2s infinite ease-in-out;
}

@keyframes logoGlow {
  0%, 100% { transform: scale(1); opacity: 0.8; box-shadow: 0 0 8px var(--primary); }
  50% { transform: scale(1.3); opacity: 1; box-shadow: 0 0 18px var(--primary), 0 0 30px var(--secondary); }
}

.nav-menu {
  display: flex;
  gap: 2.5rem;
  align-items: center;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-gray);
  position: relative;
  padding: 0.5rem 0;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-primary);
  transition: var(--transition-normal);
  border-radius: 2px;
}

.nav-link:hover, .nav-link.active {
  color: var(--text-white);
  text-shadow: 0 0 10px hsla(190, 100%, 50%, 0.3);
}

.nav-link:hover::after, .nav-link.active::after {
  width: 100%;
}

.nav-cta {
  padding: 0.6rem 1.5rem;
  border-radius: 50px;
  background: var(--gradient-primary);
  color: var(--bg-dark);
  font-weight: 600;
  box-shadow: 0 4px 15px hsla(190, 100%, 50%, 0.25);
  transition: var(--transition-normal);
}

.nav-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px hsla(190, 100%, 50%, 0.4), 0 0 10px hsla(280, 100%, 65%, 0.3);
  color: var(--bg-dark);
}

.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 6px;
  width: 30px;
  cursor: pointer;
}

.menu-toggle span {
  width: 100%;
  height: 2px;
  background-color: var(--text-white);
  transition: var(--transition-normal);
}

/* --- 渐变发光文本 & 标题 --- */
.gradient-text {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

.section-header {
  text-align: center;
  margin-bottom: 5rem;
  z-index: 1;
  position: relative;
}

.section-tag {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 3px;
  color: var(--primary);
  margin-bottom: 1rem;
  display: inline-block;
  text-shadow: 0 0 8px hsla(190, 100%, 50%, 0.2);
}

.section-title {
  font-size: 2.75rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 1.5rem;
}

.section-subtitle {
  font-size: 1.1rem;
  color: var(--text-gray);
  max-width: 600px;
  margin: 0 auto;
}

/* --- 磨砂玻璃卡片 (Glassmorphism Cards) --- */
.glass-card {
  background: var(--bg-dark-card);
  border: 1px solid var(--border-color);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border-radius: 20px;
  padding: 2.5rem;
  transition: border-color var(--transition-normal), background var(--transition-normal), transform var(--transition-normal), box-shadow var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.glass-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(800px circle at var(--mouse-x, 0) var(--mouse-y, 0), rgba(255, 255, 255, 0.05), transparent 40%);
  pointer-events: none;
  opacity: 0;
  transition: opacity var(--transition-normal);
}

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

.glass-card:hover {
  transform: translateY(-5px);
  background: var(--bg-dark-card-hover);
  border-color: var(--border-color-hover);
  box-shadow: var(--shadow-lg), 0 0 15px hsla(190, 100%, 50%, 0.05);
}

/* --- 发光发亮按钮 --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  padding: 0.9rem 2.2rem;
  border-radius: 50px;
  font-size: 1rem;
  font-weight: 600;
  transition: var(--transition-normal);
  position: relative;
  z-index: 1;
  overflow: hidden;
}

.btn-primary {
  background: var(--gradient-primary);
  color: var(--bg-dark);
  box-shadow: 0 4px 20px hsla(190, 100%, 50%, 0.3);
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px hsla(190, 100%, 50%, 0.5), 0 0 15px hsla(280, 100%, 65%, 0.4);
}

.btn-secondary {
  border: 1px solid var(--border-color);
  color: var(--text-white);
  background: hsla(0, 0%, 100%, 0.03);
  backdrop-filter: var(--glass-blur);
}

.btn-secondary:hover {
  border-color: var(--primary);
  background: hsla(0, 0%, 100%, 0.06);
  transform: translateY(-3px);
  box-shadow: 0 8px 20px hsla(190, 100%, 50%, 0.15);
}

/* --- 滚动动画类 --- */
.scroll-reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity var(--transition-slow), transform var(--transition-slow);
}

.scroll-reveal.revealed {
  opacity: 1;
  transform: translateY(0);
}

.delay-100 { transition-delay: 100ms; }
.delay-200 { transition-delay: 200ms; }
.delay-300 { transition-delay: 300ms; }
.delay-400 { transition-delay: 400ms; }
.delay-500 { transition-delay: 500ms; }

/* --- 基础页脚 --- */
.footer {
  background: hsl(230, 25%, 5%);
  border-top: 1px solid var(--border-color);
  padding: 5rem 0 2rem;
  font-size: 0.95rem;
  color: var(--text-gray);
  position: relative;
  z-index: 10;
}

.footer-layout {
  display: flex;
  flex-direction: row-reverse;
  justify-content: space-between;
  gap: 5rem;
  margin-bottom: 4rem;
}

.footer-left {
  flex: 1.3;
  max-width: 480px;
}

.footer-right {
  flex: 1;
  display: flex;
  gap: 4rem;
}

.footer-right > div {
  flex: 1;
}

.footer-brand .logo {
  margin-bottom: 1.5rem;
  display: inline-flex;
}

.footer-desc {
  line-height: 1.7;
  margin-bottom: 1.5rem;
}

.footer-socials {
  display: flex;
  gap: 1rem;
}

.social-icon {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: hsla(0, 0%, 100%, 0.05);
  border: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-white);
  font-size: 1.1rem;
  transition: var(--transition-normal);
}

.social-icon:hover {
  background: var(--gradient-primary);
  color: var(--bg-dark);
  border-color: transparent;
  transform: translateY(-3px);
  box-shadow: 0 5px 15px hsla(190, 100%, 50%, 0.3);
}

.footer-title {
  color: var(--text-white);
  font-weight: 600;
  margin-bottom: 1.5rem;
  font-size: 1.1rem;
  position: relative;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.footer-link:hover {
  color: var(--primary);
  padding-left: 5px;
}

.footer-subscribe p {
  margin-bottom: 1.25rem;
}

.subscribe-form {
  display: flex;
  border-radius: 50px;
  overflow: hidden;
  border: 1px solid var(--border-color);
  background: hsla(0, 0%, 100%, 0.02);
  padding: 0.25rem;
  transition: var(--transition-normal);
}

.subscribe-form:focus-within {
  border-color: var(--primary);
  box-shadow: var(--shadow-glow);
}

.subscribe-form input {
  background: transparent;
  border: none;
  outline: none;
  padding: 0.75rem 1.25rem;
  color: var(--text-white);
  width: 100%;
  font-family: inherit;
}

.subscribe-form button {
  background: var(--gradient-primary);
  color: var(--bg-dark);
  padding: 0 1.5rem;
  border-radius: 50px;
  font-weight: 600;
  transition: var(--transition-normal);
  white-space: nowrap;
  flex-shrink: 0;
}

.subscribe-form button:hover {
  opacity: 0.9;
}

.footer-bottom {
  border-top: 1px solid var(--border-color);
  padding-top: 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.footer-policies {
  display: flex;
  gap: 2rem;
}

/* --- 响应式断点控制 --- */
@media (max-width: 1024px) {
  .footer-layout {
    gap: 3.5rem;
  }
}

@media (max-width: 768px) {
  :root {
    --nav-height: 70px;
  }

  .section {
    padding: 6rem 0;
  }

  .section-title {
    font-size: 2.2rem;
  }

  .menu-toggle {
    display: flex;
  }

  .nav-menu {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    width: 100%;
    height: calc(100vh - var(--nav-height));
    background: hsla(230, 25%, 8%, 0.98);
    backdrop-filter: blur(20px);
    flex-direction: column;
    justify-content: center;
    gap: 2rem;
    transform: translateX(100%);
    transition: var(--transition-normal);
    border-top: 1px solid var(--border-color);
    padding: 3rem;
  }

  .nav-menu.active {
    transform: translateX(0);
  }

  .menu-toggle.active span:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
  }

  .menu-toggle.active span:nth-child(2) {
    opacity: 0;
  }

  .menu-toggle.active span:nth-child(3) {
    transform: translateY(-8px) rotate(-45deg);
  }

  .footer-layout {
    flex-direction: column-reverse;
    gap: 3rem;
  }
  .footer-right {
    gap: 2rem;
  }
  @media (max-width: 480px) {
    .footer-right {
      flex-direction: column;
    }
    .subscribe-form {
      flex-direction: column;
      border-radius: 12px;
      gap: 0.5rem;
    }
    .subscribe-form input {
      padding: 0.75rem 1.25rem;
    }
    .subscribe-form button {
      padding: 0.75rem 1.5rem;
    }
  }

  .footer-bottom {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }
}