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

:root {
  --container: 1180px;
  --primary: #0066FF;
  --primary-dark: #0052CC;
  --primary-light: #E8F0FF;
  --white: #FFFFFF;
  --gray-50: #F8F9FA;
  --gray-100: #F0F2F5;
  --gray-200: #E8EAED;
  --gray-300: #D8DCDF;
  --gray-400: #B8BCC2;
  --gray-500: #8B91A5;
  --gray-600: #5F6B7F;
  --gray-700: #3D4556;
  --gray-900: #1A1D24;
  --success: #10B981;
  --warning: #F59E0B;
  --text-primary: #1A1D24;
  --text-secondary: #5F6B7F;
  --border: #E8EAED;
  --transition: all 0.3s ease;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--text-primary);
  background-color: var(--white);
  line-height: 1.6;
}

.container {
  width: min(100% - 32px, var(--container));
  margin-inline: auto;
}

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

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

a:hover {
  color: var(--primary-dark);
}

/* 按钮 */
.btn-primary {
  display: inline-block;
  padding: 12px 32px;
  background-color: var(--primary);
  color: var(--white);
  border: none;
  border-radius: 8px;
  font-weight: 600;
  font-size: 14px;
  cursor: pointer;
  transition: var(--transition);
}

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

.btn-secondary {
  display: inline-block;
  padding: 12px 32px;
  background-color: var(--white);
  color: var(--primary);
  border: 2px solid var(--primary);
  border-radius: 8px;
  font-weight: 600;
  font-size: 14px;
  cursor: pointer;
  transition: var(--transition);
}

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

.btn-large {
  padding: 14px 40px;
  font-size: 16px;
}

.btn-download {
  display: inline-block;
  padding: 10px 24px;
  background-color: var(--primary);
  color: var(--white);
  border: none;
  border-radius: 6px;
  font-weight: 600;
  font-size: 13px;
  cursor: pointer;
  transition: var(--transition);
}

.btn-download:hover {
  background-color: var(--primary-dark);
}

/* 进度条 */
.progress-line {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  background-color: var(--primary);
  width: 0;
  z-index: 99;
  transition: width 0.3s ease;
}

/* 导航栏 */
.header {
  position: sticky;
  top: 0;
  background-color: var(--white);
  border-bottom: 1px solid var(--border);
  z-index: 95;
  transition: var(--transition);
}

.nav-content {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 40px;
  padding: 16px 0;
}

.logo {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.5px;
}

.nav-menu {
  display: flex;
  justify-content: center;
  gap: 40px;
}

.nav-link {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  transition: var(--transition);
}

.nav-link:hover {
  color: var(--primary);
}

.nav-buttons {
  display: flex;
  justify-content: flex-end;
}

/* Hero 部分 */
.hero {
  padding: 80px 0;
  background: linear-gradient(135deg, var(--primary-light) 0%, var(--white) 100%);
}

.hero-wrapper {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

h1 {
  font-size: 48px;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 16px;
  color: var(--text-primary);
}

.hero-subtitle {
  font-size: 24px;
  color: var(--text-secondary);
  margin-bottom: 16px;
  font-weight: 600;
}

.hero-description {
  font-size: 16px;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 32px;
}

.hero-buttons {
  display: flex;
  gap: 16px;
  margin-bottom: 48px;
}

.hero-stats {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 24px;
}

.stat {
  text-align: left;
}

.stat-number {
  display: block;
  font-size: 24px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 4px;
}

.stat-label {
  display: block;
  font-size: 13px;
  color: var(--text-secondary);
}

.hero-visual {
  display: flex;
  justify-content: center;
}

.phone-mockup {
  position: relative;
  display: flex;
  justify-content: center;
}

.phone-mockup img {
  max-width: 100%;
  height: auto;
  border-radius: 20px;
  box-shadow: 0 20px 60px rgba(0, 102, 255, 0.15);
}

/* 优势部分 */
.advantages {
  padding: 80px 0;
  background-color: var(--gray-50);
}

h2 {
  font-size: 36px;
  font-weight: 700;
  text-align: center;
  margin-bottom: 60px;
  color: var(--text-primary);
}

.advantages-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.advantage-card {
  padding: 32px;
  background-color: var(--white);
  border: 1px solid var(--border);
  border-radius: 12px;
  text-align: center;
  transition: var(--transition);
}

.advantage-card:hover {
  border-color: var(--primary);
  box-shadow: 0 8px 24px rgba(0, 102, 255, 0.1);
  transform: translateY(-4px);
}

.advantage-icon {
  font-size: 40px;
  margin-bottom: 16px;
}

.advantage-card h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.advantage-card p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* 功能部分 */
.features {
  padding: 80px 0;
  background-color: var(--white);
}

.features-layout {
  display: flex;
  flex-direction: column;
  gap: 80px;
}

.feature-item {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.feature-item-reverse {
  grid-template-columns: 1fr 1fr;
}

.feature-item-reverse .feature-content {
  order: 2;
}

.feature-item-reverse .feature-image {
  order: 1;
}

.feature-item h3 {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--text-primary);
}

.feature-item > .feature-content > p {
  font-size: 16px;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 24px;
}

.feature-list {
  list-style: none;
}

.feature-list li {
  padding: 8px 0;
  padding-left: 24px;
  position: relative;
  font-size: 14px;
  color: var(--text-secondary);
}

.feature-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--success);
  font-weight: 700;
}

.feature-image {
  display: flex;
  justify-content: center;
}

.feature-image img {
  border-radius: 12px;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.08);
}

/* 网络部分 */
.networks {
  padding: 80px 0;
  background-color: var(--gray-50);
}

.networks-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.network-card {
  padding: 40px;
  background-color: var(--white);
  border: 1px solid var(--border);
  border-radius: 12px;
  text-align: center;
}

.network-name {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.network-card p {
  font-size: 14px;
  color: var(--text-secondary);
}

/* 下载部分 */
.download {
  padding: 80px 0;
  background-color: var(--white);
}

.download-subtitle {
  text-align: center;
  font-size: 18px;
  color: var(--text-secondary);
  margin-bottom: 60px;
}

.download-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.download-card {
  padding: 40px;
  background-color: var(--gray-50);
  border: 1px solid var(--border);
  border-radius: 12px;
  text-align: center;
  transition: var(--transition);
}

.download-card:hover {
  border-color: var(--primary);
  box-shadow: 0 8px 24px rgba(0, 102, 255, 0.1);
}

.platform-icon {
  font-size: 48px;
  margin-bottom: 16px;
}

.download-card h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.download-card p {
  font-size: 14px;
  color: var(--text-secondary);
  margin-bottom: 24px;
}

.download-links {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.download-link {
  display: inline-block;
  padding: 10px 16px;
  background-color: var(--primary);
  color: var(--white);
  border-radius: 6px;
  font-size: 13px;
  font-weight: 600;
  transition: var(--transition);
}

.download-link:hover {
  background-color: var(--primary-dark);
}

/* 指南部分 */
.guide {
  padding: 80px 0;
  background-color: var(--gray-50);
}

.guide-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.guide-step {
  padding: 32px;
  background-color: var(--white);
  border: 1px solid var(--border);
  border-radius: 12px;
}

.step-number {
  font-size: 32px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 16px;
}

.guide-step h3 {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.guide-step p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* FAQ 部分 */
.faq {
  padding: 80px 0;
  background-color: var(--white);
}

.faq-items {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  margin-bottom: 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
}

.faq-question {
  width: 100%;
  padding: 20px;
  background-color: var(--white);
  border: none;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
  transition: var(--transition);
}

.faq-question:hover {
  background-color: var(--primary-light);
}

.faq-question.open {
  background-color: var(--primary-light);
  color: var(--primary);
}

.faq-icon {
  font-size: 18px;
  font-weight: 700;
  transition: transform 0.3s ease;
}

.faq-question.open .faq-icon {
  transform: rotate(45deg);
}

.faq-answer {
  padding: 20px;
  background-color: var(--gray-50);
  border-top: 1px solid var(--border);
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* 社区部分 */
.community {
  padding: 80px 0;
  background-color: var(--gray-50);
  text-align: center;
}

.community-text {
  font-size: 18px;
  color: var(--text-secondary);
  margin-bottom: 48px;
}

.community-channels {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  max-width: 600px;
  margin: 0 auto;
}

.community-link {
  padding: 32px;
  background-color: var(--white);
  border: 1px solid var(--border);
  border-radius: 12px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  transition: var(--transition);
  color: var(--text-primary);
}

.community-link:hover {
  border-color: var(--primary);
  background-color: var(--primary-light);
}

.channel-icon {
  font-size: 32px;
}

.channel-name {
  font-size: 14px;
  font-weight: 600;
}

/* CTA 部分 */
.cta {
  padding: 80px 0;
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: var(--white);
  text-align: center;
}

.cta h2 {
  color: var(--white);
  margin-bottom: 16px;
}

.cta p {
  font-size: 18px;
  margin-bottom: 32px;
}

.cta .btn-primary {
  padding: 16px 48px;
  background-color: var(--white);
  color: var(--primary);
}

.cta .btn-primary:hover {
  background-color: var(--gray-100);
}

/* Footer */
.footer {
  background-color: var(--gray-900);
  color: var(--white);
  padding: 60px 0 0;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 40px;
  margin-bottom: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-section h3 {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--white);
}

.footer-section p {
  font-size: 13px;
  line-height: 1.8;
  opacity: 0.8;
}

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

.footer-section li {
  margin-bottom: 8px;
}

.footer-section a {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.7);
  transition: var(--transition);
}

.footer-section a:hover {
  color: var(--white);
}

.footer-bottom {
  text-align: center;
  padding: 24px 0;
  font-size: 12px;
  opacity: 0.6;
}

/* 返回顶部 */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: var(--primary);
  color: var(--white);
  border: none;
  font-size: 18px;
  cursor: pointer;
  z-index: 80;
  transition: var(--transition);
  box-shadow: 0 4px 12px rgba(0, 102, 255, 0.3);
}

.back-to-top:hover {
  background-color: var(--primary-dark);
  transform: translateY(-4px);
}

/* 响应式 - 平板 */
@media (max-width: 1024px) {
  :root {
    --container: 900px;
  }

  h1 {
    font-size: 40px;
  }

  h2 {
    font-size: 32px;
    margin-bottom: 48px;
  }

  .nav-menu {
    gap: 24px;
  }

  .hero-wrapper {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .hero-subtitle {
    font-size: 20px;
  }

  .advantages-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .feature-item {
    grid-template-columns: 1fr;
  }

  .feature-item-reverse {
    grid-template-columns: 1fr;
  }

  .feature-item-reverse .feature-content,
  .feature-item-reverse .feature-image {
    order: unset;
  }

  .networks-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .download-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .guide-steps {
    grid-template-columns: repeat(2, 1fr);
  }

  .community-channels {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-content {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* 响应式 - 手机 */
@media (max-width: 768px) {
  :root {
    --container: 100%;
  }

  .nav-content {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .nav-menu {
    order: 3;
    width: 100%;
    flex-direction: column;
    gap: 12px;
  }

  .nav-buttons {
    order: 2;
    justify-content: center;
  }

  .hero {
    padding: 60px 0;
  }

  h1 {
    font-size: 32px;
    line-height: 1.3;
  }

  h2 {
    font-size: 26px;
    margin-bottom: 36px;
  }

  .hero-subtitle {
    font-size: 18px;
  }

  .hero-buttons {
    flex-direction: column;
    gap: 12px;
  }

  .btn-primary,
  .btn-secondary,
  .btn-large {
    width: 100%;
    text-align: center;
  }

  .hero-stats {
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
  }

  .stat-number {
    font-size: 20px;
  }

  .stat-label {
    font-size: 12px;
  }

  .advantages-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .advantage-card {
    padding: 24px;
  }

  .feature-item {
    gap: 30px;
  }

  .feature-item h3 {
    font-size: 22px;
  }

  .networks-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .download-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .guide-steps {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .community-channels {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }

  .footer-content {
    grid-template-columns: 1fr;
    gap: 24px;
  }
}

@media (max-width: 480px) {
  .container {
    width: min(100% - 16px, var(--container));
  }

  h1 {
    font-size: 28px;
  }

  h2 {
    font-size: 22px;
  }

  .hero {
    padding: 40px 0;
  }

  .advantages,
  .features,
  .networks,
  .download,
  .guide,
  .faq,
  .community,
  .cta {
    padding: 60px 0;
  }

  .hero-description {
    font-size: 15px;
  }

  .hero-stats {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .advantage-card {
    padding: 20px;
    text-align: left;
  }

  .advantage-icon {
    font-size: 32px;
  }

  .feature-list li {
    font-size: 13px;
  }

  .download-links {
    flex-direction: row;
    gap: 8px;
  }

  .download-link {
    flex: 1;
    padding: 8px 12px;
    font-size: 12px;
  }

  .faq-question {
    padding: 16px;
    font-size: 14px;
  }

  .faq-answer {
    padding: 16px;
    font-size: 13px;
  }

  .community-channels {
    grid-template-columns: 1fr;
  }
}