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

:root {
  --primary-color: #2563eb;
  --primary-dark: #1e40af;
  --secondary-color: #64748b;
  --text-color: #1e293b;
  --text-light: #64748b;
  --bg-color: #ffffff;
  --bg-light: #f8fafc;
  --border-color: #e2e8f0;
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
    'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue',
    sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  color: var(--text-color);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.btn {
  display: inline-block;
  padding: 12px 24px;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  transition: all 0.3s ease;
  border: none;
  cursor: pointer;
  font-size: 16px;
}

.btn-primary {
  background: var(--primary-color);
  color: white;
}

.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

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

.btn-secondary:hover {
  background: var(--primary-color);
  color: white;
}

.section-title {
  font-size: 2.5rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 3rem;
  color: var(--text-color);
}

/* 导航栏 */
.navbar {
  background: white;
  box-shadow: var(--shadow);
  position: sticky;
  top: 0;
  z-index: 1000;
  padding: 1rem 0;
}

.navbar-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.navbar-logo {
  text-decoration: none;
  color: var(--primary-color);
  font-size: 1.5rem;
  font-weight: 700;
}

.logo-text {
  background: linear-gradient(135deg, var(--primary-color), #3b82f6);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.navbar-menu {
  display: flex;
  gap: 2rem;
  align-items: center;
}

.navbar-link {
  text-decoration: none;
  color: var(--text-color);
  font-weight: 500;
  transition: color 0.3s ease;
  position: relative;
}

.navbar-link:hover,
.navbar-link.active {
  color: var(--primary-color);
}

.navbar-link.active::after {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--primary-color);
}

.navbar-toggle {
  display: none;
  flex-direction: column;
  cursor: pointer;
  gap: 5px;
}

.navbar-toggle span {
  width: 25px;
  height: 3px;
  background: var(--text-color);
  border-radius: 3px;
  transition: all 0.3s ease;
}

/* 页面切换 */
.page {
  display: none;
  flex: 1;
}

.page.active {
  display: block;
}

/* 首页样式 */
.hero {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 6rem 0;
  display: flex;
  align-items: center;
  min-height: 600px;
}

.hero-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

.hero-title {
  font-size: 3rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  line-height: 1.2;
}

.hero-subtitle {
  font-size: 1.25rem;
  margin-bottom: 2rem;
  opacity: 0.9;
  line-height: 1.6;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.hero-image {
  display: flex;
  justify-content: center;
  align-items: center;
}

.hero-placeholder {
  width: 300px;
  height: 300px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.tech-icon {
  font-size: 6rem;
}

.features {
  padding: 5rem 0;
  background: var(--bg-light);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
}

.feature-card {
  background: white;
  padding: 2rem;
  border-radius: 12px;
  text-align: center;
  box-shadow: var(--shadow);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.feature-icon {
  font-size: 3rem;
  margin-bottom: 1rem;
}

.feature-card h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--text-color);
}

.feature-card p {
  color: var(--text-light);
  line-height: 1.6;
}

.app-preview {
  padding: 5rem 0;
  background: white;
}

.app-preview-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

.app-preview-text h2 {
  font-size: 2.5rem;
  margin-bottom: 1.5rem;
  color: var(--text-color);
}

.app-description {
  font-size: 1.1rem;
  color: var(--text-light);
  margin-bottom: 2rem;
  line-height: 1.8;
}

.phone-mockup {
  width: 250px;
  height: 500px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius: 30px;
  padding: 15px;
  box-shadow: var(--shadow-lg);
  margin: 0 auto;
}

.phone-screen {
  width: 100%;
  height: 100%;
  background: white;
  border-radius: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 1rem;
}

.app-logo-large {
  font-size: 2rem;
  font-weight: 700;
  color: var(--primary-color);
}

/* 关于我们 */
.about-hero {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 4rem 0;
  text-align: center;
}

.about-hero h1 {
  font-size: 3rem;
  margin-bottom: 1rem;
}

.about-intro {
  font-size: 1.25rem;
  max-width: 800px;
  margin: 0 auto;
  opacity: 0.9;
  line-height: 1.8;
}

.about-content {
  padding: 5rem 0;
  background: var(--bg-light);
}

.about-section {
  margin-bottom: 4rem;
}

.about-section h2 {
  font-size: 2rem;
  margin-bottom: 1.5rem;
  color: var(--text-color);
}

.about-section p {
  font-size: 1.1rem;
  color: var(--text-light);
  line-height: 1.8;
  max-width: 900px;
}

.values-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}

.value-item {
  background: white;
  padding: 2rem;
  border-radius: 12px;
  text-align: center;
  box-shadow: var(--shadow);
  transition: transform 0.3s ease;
}

.value-item:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.value-item h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--primary-color);
}

.value-item p {
  color: var(--text-light);
}

/* 产品页面 */
.app-hero {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 4rem 0;
  text-align: center;
}

.app-title {
  font-size: 4rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

.app-tagline {
  font-size: 1.5rem;
  opacity: 0.9;
}

.app-details {
  padding: 5rem 0;
  background: var(--bg-light);
}

.app-showcase {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: start;
}

.app-image-section {
  position: sticky;
  top: 100px;
}

.phone-mockup-large {
  width: 300px;
  height: 600px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius: 40px;
  padding: 20px;
  box-shadow: var(--shadow-lg);
  margin: 0 auto;
}

.phone-screen-large {
  width: 100%;
  height: 100%;
  background: white;
  border-radius: 30px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2rem;
  padding: 2rem;
}

.app-logo-display {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--primary-color);
  text-align: center;
}

.app-features-preview {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  width: 100%;
}

.feature-dot {
  width: 100%;
  height: 60px;
  background: var(--bg-light);
  border-radius: 12px;
  animation: pulse 2s infinite;
}

.feature-dot:nth-child(2) {
  animation-delay: 0.5s;
}

.feature-dot:nth-child(3) {
  animation-delay: 1s;
}

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

.app-info-section h2 {
  font-size: 2rem;
  margin-bottom: 1.5rem;
  color: var(--text-color);
}

.app-features {
  margin-bottom: 3rem;
}

.app-features h3 {
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
  color: var(--text-color);
}

.features-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.features-list li {
  display: flex;
  gap: 1rem;
  align-items: start;
}

.features-list li .feature-icon {
  font-size: 2rem;
  flex-shrink: 0;
}

.features-list li div {
  flex: 1;
}

.features-list li strong {
  display: block;
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
  color: var(--text-color);
}

.features-list li p {
  color: var(--text-light);
  line-height: 1.6;
}

.app-download h3 {
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
  color: var(--text-color);
}

.download-buttons {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.download-btn {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 1rem 2rem;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: all 0.3s ease;
  background: var(--text-color);
  color: white;
}

.download-btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.download-btn.ios {
  background: #000;
}

.download-btn.android {
  background: #3ddc84;
}

/* 联系我们 */
.contact-hero {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 4rem 0;
  text-align: center;
}

.contact-hero h1 {
  font-size: 3rem;
  margin-bottom: 1rem;
}

.contact-hero p {
  font-size: 1.25rem;
  opacity: 0.9;
}

.contact-content {
  padding: 5rem 0;
  background: var(--bg-light);
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
}

.contact-info h2 {
  font-size: 2rem;
  margin-bottom: 2rem;
  color: var(--text-color);
}

.contact-item {
  display: flex;
  gap: 1.5rem;
  margin-bottom: 2rem;
  align-items: start;
}

.contact-icon {
  font-size: 2rem;
  flex-shrink: 0;
}

.contact-item h3 {
  font-size: 1.2rem;
  margin-bottom: 0.5rem;
  color: var(--text-color);
}

.contact-item p {
  color: var(--text-light);
  line-height: 1.6;
}

.contact-form-section h2 {
  font-size: 2rem;
  margin-bottom: 2rem;
  color: var(--text-color);
}

.contact-form {
  background: white;
  padding: 2rem;
  border-radius: 12px;
  box-shadow: var(--shadow);
}

.form-group {
  margin-bottom: 1.5rem;
}

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 600;
  color: var(--text-color);
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 0.75rem;
  border: 2px solid var(--border-color);
  border-radius: 8px;
  font-size: 1rem;
  font-family: inherit;
  transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--primary-color);
}

.form-group textarea {
  resize: vertical;
  min-height: 120px;
}

.btn-submit {
  width: 100%;
  padding: 1rem;
  font-size: 1.1rem;
}

/* 页脚 */
.footer {
  background: var(--text-color);
  color: white;
  margin-top: auto;
  padding: 3rem 0 1rem;
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  margin-bottom: 2rem;
}

.footer-section h3,
.footer-section h4 {
  margin-bottom: 1rem;
  color: white;
}

.footer-section p {
  color: rgba(255, 255, 255, 0.8);
  line-height: 1.8;
}

.footer-section ul {
  list-style: none;
}

.footer-section ul li {
  margin-bottom: 0.5rem;
}

.footer-section ul li a {
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  transition: color 0.3s ease;
}

.footer-section ul li a:hover {
  color: white;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 1rem;
  text-align: center;
}

.footer-bottom p {
  color: rgba(255, 255, 255, 0.6);
  font-size: 0.9rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
  .section-title {
    font-size: 2rem;
  }

  .navbar-toggle {
    display: flex;
  }

  .navbar-menu {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: white;
    flex-direction: column;
    padding: 1rem;
    box-shadow: var(--shadow-lg);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    gap: 1rem;
  }

  .navbar-menu.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .navbar-link {
    width: 100%;
    padding: 0.5rem 0;
  }

  .hero {
    padding: 4rem 0;
    min-height: auto;
  }

  .hero-content {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-title {
    font-size: 2rem;
  }

  .hero-subtitle {
    font-size: 1rem;
  }

  .hero-placeholder {
    width: 200px;
    height: 200px;
  }

  .tech-icon {
    font-size: 4rem;
  }

  .app-preview-content {
    grid-template-columns: 1fr;
  }

  .phone-mockup {
    width: 200px;
    height: 400px;
  }

  .about-hero h1 {
    font-size: 2rem;
  }

  .about-intro {
    font-size: 1rem;
  }

  .about-section h2 {
    font-size: 1.5rem;
  }

  .app-showcase {
    grid-template-columns: 1fr;
  }

  .app-image-section {
    position: static;
  }

  .phone-mockup-large {
    width: 250px;
    height: 500px;
  }

  .app-title {
    font-size: 2.5rem;
  }

  .app-tagline {
    font-size: 1.2rem;
  }

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

  .contact-hero h1 {
    font-size: 2rem;
  }

  .contact-hero p {
    font-size: 1rem;
  }
}