/* WhatsApp Web 中文站 - 全局样式 */

:root {
  --primary: #25D366;
  --primary-dark: #128C7E;
  --accent: #34B7F1;
  --bg-main: #FEFEFF;
  --bg-secondary: #F0F2F5;
  --text-primary: #111B21;
  --text-secondary: #667781;
  --card-bg: #FFFFFF;
  --shadow: 0 2px 12px rgba(0,0,0,0.08);
  --shadow-hover: 0 8px 24px rgba(0,0,0,0.12);
  --radius: 12px;
  --transition: all 0.3s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg-main);
  color: var(--text-primary);
  line-height: 1.7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

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

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text-primary);
}

.logo-icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.logo-icon svg {
  width: 24px;
  height: 24px;
  fill: white;
}

.logo-text {
  font-weight: 700;
  font-size: 1.2rem;
}

.logo-text span {
  color: var(--primary);
}

.nav-links {
  display: flex;
  gap: 8px;
  list-style: none;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-secondary);
  padding: 8px 16px;
  border-radius: 8px;
  font-weight: 500;
  transition: var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
  background: var(--bg-secondary);
  color: var(--primary);
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.mobile-menu-btn svg {
  width: 24px;
  height: 24px;
  fill: var(--text-primary);
}

/* 主内容 */
main {
  flex: 1;
}

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

.hero h1 {
  font-size: 2.8rem;
  margin-bottom: 16px;
  font-weight: 800;
}

.hero p {
  font-size: 1.2rem;
  opacity: 0.95;
  max-width: 600px;
  margin: 0 auto 32px;
}

.hero-buttons {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: 50px;
  text-decoration: none;
  font-weight: 600;
  transition: var(--transition);
}

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

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(0,0,0,0.2);
}

.btn-secondary {
  background: transparent;
  border: 2px solid white;
  color: white;
}

.btn-secondary:hover {
  background: rgba(255,255,255,0.1);
}

/* 面包屑 */
.breadcrumb {
  padding: 16px 0;
  background: var(--bg-secondary);
}

.breadcrumb-list {
  display: flex;
  align-items: center;
  gap: 8px;
  list-style: none;
  font-size: 0.9rem;
}

.breadcrumb-list a {
  color: var(--text-secondary);
  text-decoration: none;
}

.breadcrumb-list a:hover {
  color: var(--primary);
}

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

/* 区块标题 */
.section-title {
  text-align: center;
  margin-bottom: 48px;
}

.section-title h2 {
  font-size: 2rem;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.section-title p {
  color: var(--text-secondary);
  font-size: 1.1rem;
}

/* 卡片网格 */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
  padding: 60px 0;
}

.card {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 32px;
  box-shadow: var(--shadow);
  transition: var(--transition);
  text-decoration: none;
  color: inherit;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
}

.card-icon {
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

.card-icon svg {
  width: 28px;
  height: 28px;
  fill: white;
}

.card h3 {
  font-size: 1.3rem;
  margin-bottom: 12px;
  color: var(--text-primary);
}

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

/* 内容区块 */
.section {
  padding: 60px 0;
}

.section.bg-secondary {
  background: var(--bg-secondary);
}

.content-block {
  max-width: 800px;
  margin: 0 auto;
}

.content-block h2 {
  font-size: 1.8rem;
  margin-bottom: 20px;
  color: var(--text-primary);
}

.content-block h3 {
  font-size: 1.4rem;
  margin: 32px 0 16px;
  color: var(--text-primary);
}

.content-block p {
  margin-bottom: 16px;
  color: var(--text-secondary);
}

.content-block ul {
  margin: 16px 0;
  padding-left: 24px;
}

.content-block li {
  margin-bottom: 8px;
  color: var(--text-secondary);
}

/* 步骤列表 */
.steps {
  counter-reset: step;
}

.step {
  display: flex;
  gap: 20px;
  margin-bottom: 32px;
  padding: 24px;
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.step::before {
  counter-increment: step;
  content: counter(step);
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 700;
  font-size: 1.2rem;
}

.step-content h4 {
  font-size: 1.2rem;
  margin-bottom: 8px;
}

.step-content p {
  color: var(--text-secondary);
  margin: 0;
}

/* FAQ 手风琴 */
.faq-item {
  background: var(--card-bg);
  border-radius: var(--radius);
  margin-bottom: 16px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.faq-question {
  width: 100%;
  padding: 20px 24px;
  background: none;
  border: none;
  text-align: left;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-primary);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: var(--transition);
}

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

.faq-question svg {
  width: 20px;
  height: 20px;
  fill: var(--text-secondary);
  transition: transform 0.3s ease;
}

.faq-item.active .faq-question svg {
  transform: rotate(180deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
}

.faq-item.active .faq-answer {
  max-height: 500px;
}

.faq-answer-content {
  padding: 0 24px 20px;
  color: var(--text-secondary);
}

/* 下载卡片 */
.download-card {
  display: flex;
  align-items: center;
  gap: 24px;
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
  margin-bottom: 20px;
}

.download-icon {
  width: 64px;
  height: 64px;
  background: var(--bg-secondary);
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
}

.download-info {
  flex: 1;
}

.download-info h4 {
  font-size: 1.2rem;
  margin-bottom: 4px;
}

.download-info p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin: 0;
}

.download-btn {
  padding: 12px 24px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 50px;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  transition: var(--transition);
}

.download-btn:hover {
  background: var(--primary-dark);
  transform: scale(1.02);
}

/* 联系表单 */
.contact-form {
  max-width: 600px;
  margin: 0 auto;
  background: var(--card-bg);
  padding: 40px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  margin-bottom: 8px;
  font-weight: 500;
  color: var(--text-primary);
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 14px 16px;
  border: 2px solid var(--bg-secondary);
  border-radius: 8px;
  font-size: 1rem;
  font-family: inherit;
  transition: var(--transition);
}

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

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

.submit-btn {
  width: 100%;
  padding: 16px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

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

/* 页脚 */
.footer {
  background: var(--text-primary);
  color: white;
  padding: 60px 0 24px;
  margin-top: auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 40px;
  margin-bottom: 40px;
}

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

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

.footer-col a {
  color: rgba(255,255,255,0.7);
  text-decoration: none;
  display: block;
  padding: 6px 0;
  transition: var(--transition);
}

.footer-col a:hover {
  color: var(--primary);
}

.footer-bottom {
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid rgba(255,255,255,0.1);
  color: rgba(255,255,255,0.6);
  font-size: 0.9rem;
}

/* 移动端响应 */
@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 70px;
    left: 0;
    right: 0;
    background: var(--card-bg);
    flex-direction: column;
    padding: 16px;
    box-shadow: var(--shadow);
  }

  .nav-links.active {
    display: flex;
  }

  .mobile-menu-btn {
    display: block;
  }

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

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

  .section-title h2 {
    font-size: 1.6rem;
  }

  .download-card {
    flex-direction: column;
    text-align: center;
  }

  .contact-form {
    padding: 24px;
  }
}

/* 动画 */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.card, .step, .faq-item {
  animation: fadeInUp 0.5s ease-out;
}

/* 工具类 */
.text-center { text-align: center; }
.mt-4 { margin-top: 32px; }
.mb-4 { margin-bottom: 32px; }