/* 全局样式重置 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #3b82f6;
  --primary-lighter: #60a5fa;
  --primary-bg: #eff6ff;
  --secondary: #0ea5e9;
  --accent: #22c55e;
  --text-dark: #0f172a;
  --text-medium: #334155;
  --text-light: #64748b;
  --text-lighter: #94a3b8;
  --bg-light: #f8fafc;
  --bg-white: #ffffff;
  --bg-dark: #0f172a;
  --bg-darker: #020617;
  --border-light: #e2e8f0;
  --border-lighter: #f1f5f9;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  font-size: 16px;
  line-height: 1.7;
  letter-spacing: 0.01em;
  color: var(--text-dark);
  background-color: var(--bg-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0%;
  background: linear-gradient(90deg, #3b82f6, #06b6d4);
  z-index: 9999;
  transition: width 0.1s ease-out;
}

.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, #2563eb 0%, #3b82f6 100%);
  color: white;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 8px 24px rgba(37, 99, 235, 0.3);
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: all 0.3s ease;
  z-index: 999;
}

/* 客服聊天面板打开时：把回到顶部按钮移到左下角，避免和聊天面板/悬浮按钮重叠 */
body.cs-panel-open .back-to-top {
  right: auto;
  left: 30px;
  bottom: 30px;
}

.back-to-top.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(37, 99, 235, 0.4);
}

.back-to-top:active {
  transform: scale(0.95);
}

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

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

.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 40px;
}

/* 导航栏 */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: #ffffff;
  border-bottom: 1px solid #f1f5f9;
  z-index: 1000;
  transition: all 0.3s ease;
}

.navbar.scrolled {
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
}

.nav-container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 32px;
  height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo-link {
  text-decoration: none;
  color: inherit;
  display: block;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo-icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  overflow: hidden;
  flex-shrink: 0;
}

.logo-icon img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.logo-text {
  display: flex;
  flex-direction: column;
}

.logo-title {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 18px;
  font-weight: 700;
  color: var(--text-dark);
}

.logo-badge {
  font-size: 11px;
  font-weight: 500;
  color: var(--primary);
  background: var(--primary-bg);
  padding: 2px 8px;
  border-radius: 20px;
  border: 1px solid #bfdbfe;
}

.logo-subtitle {
  font-size: 12px;
  color: var(--text-light);
  margin-top: 2px;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-link {
  padding: 8px 18px;
  font-size: 15px;
  font-weight: 500;
  color: var(--text-medium);
  border-radius: 8px;
  transition: all 0.2s ease;
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, #3b82f6, #06b6d4);
  border-radius: 1px;
  transition: width 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 60%;
}

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

.nav-link.active {
  color: var(--primary);
  font-weight: 600;
}

.nav-download-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px 24px;
  background: linear-gradient(135deg, #2563eb 0%, #3b82f6 100%);
  color: white;
  font-size: 15px;
  font-weight: 600;
  border-radius: 999px;
  transition: all 0.2s ease;
  box-shadow: 0 4px 14px 0 rgba(37, 99, 235, 0.3);
}

.nav-download-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 20px 0 rgba(37, 99, 235, 0.4);
}

/* Hero 区域 */
.hero {
  padding: 100px 0 60px;
  background: linear-gradient(180deg, #eff6ff 0%, #f8fafc 60%, #ffffff 100%);
  position: relative;
  overflow: hidden;
}

.hero-container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 32px;
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 40px;
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: #dbeafe;
  border: 1px solid #93c5fd;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 28px;
}

.hero-title {
  font-size: 60px;
  font-weight: 900;
  line-height: 1.15;
  color: var(--text-dark);
  margin-bottom: 28px;
  letter-spacing: -0.02em;
}

.hero-title-blue {
  background: linear-gradient(135deg, #2563eb 0%, #0ea5e9 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-tags {
  display: flex;
  gap: 8px;
  margin-bottom: 28px;
}

.tag {
  padding: 6px 14px;
  font-size: 14px;
  font-weight: 600;
  border-radius: 6px;
}

.tag-red {
  color: #dc2626;
  background: #fef2f2;
  border: 1px solid #fecaca;
}

.hero-desc {
  font-size: 17px;
  line-height: 1.8;
  color: var(--text-medium);
  margin-bottom: 36px;
  max-width: 520px;
}

.hero-features {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  margin-bottom: 32px;
}

.hero-feature-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px 18px;
  background: #f8fafc;
  border: 1px solid #e2e8f0;
  border-radius: 16px;
}

.hero-feature-icon {
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.hero-feature-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--primary);
  line-height: 1.3;
}

.hero-feature-sub {
  font-size: 13px;
  color: var(--text-light);
  margin-top: 3px;
}

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 18px 40px;
  font-size: 18px;
  font-weight: 600;
  border-radius: 999px;
  cursor: pointer;
  transition: all 0.2s ease;
  user-select: none;
  border: none;
  outline: none;
}

.btn:active {
  transform: scale(0.97);
}

.btn-primary {
  background: linear-gradient(135deg, #2563eb 0%, #3b82f6 100%);
  color: white;
  box-shadow: 0 8px 24px 0 rgba(37, 99, 235, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 32px 0 rgba(37, 99, 235, 0.4);
}

.btn-secondary {
  background: white;
  color: var(--text-dark);
  border: 2px solid var(--border-light);
}

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

.hero-image {
  position: relative;
  width: 100%;
  height: 700px;
}

.hero-phone {
  position: absolute;
  opacity: 0;
  animation-fill-mode: forwards;
}

.hero-phone img {
  width: 100%;
  height: auto;
  filter: drop-shadow(0 20px 40px rgba(59, 130, 246, 0.25));
}

.hero-phone-parent {
  width: 92%;
  left: -6%;
  top: 30px;
  z-index: 2;
  animation: slideInLeft 1s ease-out 0.3s forwards;
}

.hero-phone-child {
  width: 78%;
  right: -6%;
  top: 110px;
  z-index: 1;
  animation: slideInRight 1s ease-out 0.5s forwards;
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-100px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translateX(100px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

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

.section-title {
  font-size: 36px;
  font-weight: 800;
  color: var(--text-dark);
  margin-bottom: 16px;
  letter-spacing: -0.02em;
  position: relative;
  display: inline-block;
  background: linear-gradient(135deg, #1e293b 0%, #3b82f6 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-title::before {
  content: '';
  position: absolute;
  left: -12px;
  top: 50%;
  transform: translateY(-50%);
  width: 4px;
  height: 60%;
  background: linear-gradient(180deg, #3b82f6, #06b6d4);
  border-radius: 2px;
}

.section-subtitle {
  font-size: 16px;
  color: var(--text-light);
  max-width: 600px;
  margin: 0 auto;
  line-height: 1.7;
}

/* 核心功能 */
.features {
  padding: 60px 0;
  background: var(--bg-white);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 24px;
}

.feature-card {
  background: linear-gradient(180deg, #fafbfc 0%, #ffffff 100%);
  border: 2px solid #f1f5f9;
  border-radius: 20px;
  padding: 24px 16px;
  text-align: center;
  transition: all 0.3s ease;
  box-shadow: 0 4px 12px -4px rgba(0, 0, 0, 0.05);
}

@property --border-progress {
  syntax: '<angle>';
  initial-value: 0deg;
  inherits: false;
}

.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 40px -15px rgba(59, 130, 246, 0.2);
  border: 2px solid transparent;
  background-image: 
    linear-gradient(180deg, #fafbfc 0%, #ffffff 100%),
    conic-gradient(from -90deg, #8b5cf6, #3b82f6, #06b6d4, #10b981, #8b5cf6 var(--border-progress), #f1f5f9 var(--border-progress), #f1f5f9);
  background-origin: padding-box, border-box;
  background-clip: padding-box, border-box;
  animation: border-sweep 0.8s linear forwards;
}

.feature-card.sweep-done {
  border-color: #3b82f6;
  background-image: none;
  animation: none;
}

@keyframes border-sweep {
  from {
    --border-progress: 0deg;
  }
  to {
    --border-progress: 360deg;
  }
}

.feature-icon {
  width: 72px;
  height: 72px;
  margin: 0 auto 16px;
  transition: transform 0.3s ease;
}

.feature-card:hover .feature-icon {
  transform: translateY(-4px) scale(1.08);
}

.feature-icon img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.feature-card-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 12px;
}

.feature-card-desc {
  font-size: 13px;
  color: var(--text-light);
  line-height: 1.6;
}

/* 安全技术 */
.security {
  padding: 60px 0;
  background: 
    radial-gradient(ellipse at 70% 50%, rgba(59, 130, 246, 0.2) 0%, transparent 50%),
    repeating-linear-gradient(0deg, transparent, transparent 39px, rgba(59, 130, 246, 0.12) 40px),
    repeating-linear-gradient(90deg, transparent, transparent 39px, rgba(59, 130, 246, 0.12) 40px),
    linear-gradient(180deg, #0f172a 0%, #020617 100%);
  position: relative;
  overflow: hidden;
}

.security::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(ellipse at 80% 50%, rgba(59, 130, 246, 0.12) 0%, transparent 60%);
  pointer-events: none;
}

.security .container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  position: relative;
  z-index: 1;
}

.security-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 18px;
  background: rgba(59, 130, 246, 0.15);
  border: 1px solid rgba(59, 130, 246, 0.3);
  border-radius: 999px;
  font-size: 14px;
  font-weight: 600;
  color: #93c5fd;
  margin-bottom: 28px;
}

.security-title {
  font-size: 44px;
  font-weight: 800;
  color: white;
  line-height: 1.25;
  margin-bottom: 24px;
  letter-spacing: -0.02em;
}

.security-desc {
  font-size: 16px;
  color: #94a3b8;
  line-height: 1.8;
  margin-bottom: 40px;
  max-width: 520px;
}

.security-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.security-item {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 20px;
  background: rgba(30, 41, 59, 0.6);
  border: 1px solid rgba(71, 85, 105, 0.5);
  border-radius: 16px;
  backdrop-filter: blur(10px);
}

.security-item-icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(59, 130, 246, 0.15);
  border-radius: 12px;
  flex-shrink: 0;
}

.security-item-title {
  font-size: 15px;
  font-weight: 600;
  color: white;
  margin-bottom: 4px;
}

.security-item-desc {
  font-size: 13px;
  color: #94a3b8;
}

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

.security-image-wrapper {
  position: relative;
  width: 100%;
  max-width: 380px;
  padding: 40px 32px 32px;
  background: linear-gradient(180deg, rgba(30, 41, 59, 0.8) 0%, rgba(15, 23, 42, 0.9) 100%);
  border: 1px solid rgba(71, 85, 105, 0.6);
  border-radius: 28px;
  text-align: center;
  backdrop-filter: blur(10px);
}

.security-image-wrapper img {
  width: 100%;
  max-width: 280px;
  margin: 0 auto 24px;
  border-radius: 20px;
  filter: drop-shadow(0 0 25px rgba(59, 130, 246, 0.5));
  animation: shield-float 4s ease-in-out infinite, shield-glow 3s ease-in-out infinite;
}

@keyframes shield-float {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-12px);
  }
}

@keyframes shield-glow {
  0%, 100% {
    filter: drop-shadow(0 0 25px rgba(59, 130, 246, 0.5));
  }
  50% {
    filter: drop-shadow(0 0 50px rgba(96, 165, 250, 0.8));
  }
}

.security-image-caption {
  text-align: center;
}

.security-caption-title {
  font-size: 22px;
  font-weight: 700;
  color: white;
  margin-bottom: 8px;
}

.security-caption-sub {
  font-size: 14px;
  color: #94a3b8;
}

/* 下载中心 */
.download {
  padding: 60px 0;
  background: var(--bg-light);
}

.download-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.download-card {
  background: white;
  border: 2px solid #f1f5f9;
  border-radius: 24px;
  padding: 32px;
  position: relative;
  transition: all 0.3s ease;
  display: flex;
  flex-direction: column;
  box-shadow: 0 8px 24px -8px rgba(0, 0, 0, 0.08);
}

.download-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 40px -15px rgba(59, 130, 246, 0.2);
  border: 2px solid transparent;
  background-image: 
    linear-gradient(white, white),
    conic-gradient(from -90deg, #8b5cf6, #3b82f6, #06b6d4, #10b981, #8b5cf6 var(--border-progress), #f1f5f9 var(--border-progress), #f1f5f9);
  background-origin: padding-box, border-box;
  background-clip: padding-box, border-box;
  animation: border-sweep 0.8s linear forwards;
}

.download-card.sweep-done {
  border-color: #3b82f6;
  background-image: none;
  animation: none;
}

.download-card-highlight {
  border: 2px solid #93c5fd;
  box-shadow: 0 10px 40px -10px rgba(59, 130, 246, 0.15);
}

.download-card-highlight:hover {
  border: 2px solid transparent;
  background-image: 
    linear-gradient(white, white),
    conic-gradient(from -90deg, #8b5cf6, #2563eb, #06b6d4, #10b981, #8b5cf6 var(--border-progress), #93c5fd var(--border-progress), #93c5fd);
  background-origin: padding-box, border-box;
  background-clip: padding-box, border-box;
  animation: border-sweep 0.8s linear forwards;
}

.download-card-highlight.sweep-done {
  border-color: #2563eb;
  background-image: none;
  animation: none;
}

.download-badge {
  position: absolute;
  top: -14px;
  right: 32px;
  padding: 6px 16px;
  background: var(--primary);
  color: white;
  font-size: 13px;
  font-weight: 600;
  border-radius: 999px;
}

.download-card-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 28px;
}

.download-icon {
  width: 56px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 16px;
  flex-shrink: 0;
}

.download-icon-blue {
  background: linear-gradient(135deg, #dbeafe 0%, #bfdbfe 100%);
  color: var(--primary);
}

.download-icon-cyan {
  background: linear-gradient(135deg, #cffafe 0%, #a5f3fc 100%);
  color: #0891b2;
}

.download-icon-green {
  background: linear-gradient(135deg, #dcfce7 0%, #bbf7d0 100%);
  color: #16a34a;
}

.download-title {
  font-size: 24px;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 4px;
}

.download-subtitle {
  font-size: 14px;
  color: var(--text-light);
}

.download-qr {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 20px;
  background: var(--bg-light);
  border-radius: 16px;
  margin-bottom: 24px;
  height: 140px;
  box-sizing: border-box;
}

.qr-image {
  width: 100px;
  height: 100px;
  background: white;
  border: 1px solid var(--border-light);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  overflow: hidden;
  padding: 8px;
}

.qr-image img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.qr-info {
  flex: 1;
}

.qr-text {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-dark);
  margin-bottom: 8px;
}

.qr-version {
  font-size: 12px;
  color: var(--text-light);
  margin-bottom: 4px;
}

.qr-size {
  font-size: 12px;
  color: var(--text-light);
}

/* 双二维码布局（家长端） */
.download-qr-row {
  display: flex;
  gap: 16px;
  padding: 20px;
  background: var(--bg-light);
  border-radius: 16px;
  margin-bottom: 24px;
  box-sizing: border-box;
}

.download-qr-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.download-qr-item .qr-image {
  width: 120px;
  height: 120px;
  margin-bottom: 10px;
}

.download-qr-item .qr-info {
  flex: none;
  width: 100%;
}

.qr-platform-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: 12px;
  margin-bottom: 10px;
}

.qr-tag-android {
  background: #e8f5e9;
  color: #2e7d32;
}

.qr-tag-ios {
  background: #e3f2fd;
  color: #1565c0;
}

.download-activate {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 20px;
  background: var(--bg-light);
  border-radius: 16px;
  margin-bottom: 24px;
  height: 140px;
  box-sizing: border-box;
}

.activate-icon {
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.activate-icon svg {
  width: 32px;
  height: 32px;
}

.activate-text {
  font-size: 13px;
  color: var(--text-light);
  line-height: 1.7;
}

.btn-download {
  width: 100%;
  padding: 16px 24px;
  font-size: 16px;
  font-weight: 600;
  border-radius: 14px;
  margin-bottom: 20px;
  box-shadow: 0 4px 12px 0 rgba(0, 0, 0, 0.1);
}

.btn-download-blue {
  background: linear-gradient(135deg, #2563eb 0%, #3b82f6 100%);
  color: white;
}

.btn-download-blue:hover {
  box-shadow: 0 6px 20px 0 rgba(37, 99, 235, 0.3);
}

.btn-download-cyan {
  background: linear-gradient(135deg, #0891b2 0%, #06b6d4 100%);
  color: white;
}

.btn-download-cyan:hover {
  box-shadow: 0 6px 20px 0 rgba(8, 145, 178, 0.3);
}

.btn-download-green {
  background: linear-gradient(135deg, #16a34a 0%, #22c55e 100%);
  color: white;
}

.btn-download-green:hover {
  box-shadow: 0 6px 20px 0 rgba(34, 197, 94, 0.3);
}

.btn-download-blue-light {
  background: linear-gradient(135deg, #3b82f6 0%, #60a5fa 100%);
  color: white;
}

.btn-download-blue-light:hover {
  box-shadow: 0 6px 20px 0 rgba(59, 130, 246, 0.3);
}

.btn-download-cyan-light {
  background: linear-gradient(135deg, #06b6d4 0%, #22d3ee 100%);
  color: white;
}

.btn-download-cyan-light:hover {
  box-shadow: 0 6px 20px 0 rgba(6, 182, 212, 0.3);
}

.btn-download-green-light {
  background: linear-gradient(135deg, #22c55e 0%, #4ade80 100%);
  color: white;
}

.btn-download-green-light:hover {
  box-shadow: 0 6px 20px 0 rgba(34, 197, 94, 0.3);
}

.download-buttons {
  display: flex;
  flex-wrap: nowrap;
  gap: 12px;
  margin-bottom: 20px;
  margin-top: auto;
}

.download-buttons .btn-download {
  flex: 1 1 0;
  min-width: 0;
  margin-bottom: 0;
  justify-content: center;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.download-support {
  text-align: center;
  margin-top: auto;
}

.download-support p {
  font-size: 13px;
  color: var(--text-light);
  line-height: 1.8;
}

/* 使用指南 */
.guide {
  padding: 60px 0;
  background: var(--bg-white);
}

.guide-steps {
  display: flex;
  align-items: stretch;
  justify-content: center;
  gap: 24px;
  max-width: 1100px;
  margin: 0 auto;
}

.guide-step {
  flex: 1;
  padding: 28px 24px;
  background: var(--bg-light);
  border-radius: 16px;
  display: flex;
  align-items: center;
  gap: 16px;
  border: 1px solid var(--border-light);
}

.step-number {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
  color: #2563eb;
  font-size: 24px;
  font-weight: 700;
  border-radius: 12px;
  flex-shrink: 0;
}

.step-content {
  flex: 1;
}

.step-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 6px;
}

.step-desc {
  font-size: 14px;
  color: var(--text-light);
  line-height: 1.6;
}

.step-arrow {
  display: none;
}

/* 常见问题 */
.faq {
  padding: 60px 0;
  background: var(--bg-light);
}

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

.faq-item {
  background: white;
  border: 1px solid var(--border-light);
  border-radius: 16px;
  margin-bottom: 16px;
  overflow: hidden;
  transition: all 0.2s ease;
}

.faq-item:hover {
  border-color: var(--primary-lighter);
  box-shadow: 0 4px 12px 0 rgba(0, 0, 0, 0.05);
}

.faq-item.active {
  border-color: var(--primary);
  box-shadow: 0 4px 12px 0 rgba(37, 99, 235, 0.1);
}

.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 22px 24px;
  cursor: pointer;
  font-size: 16px;
  font-weight: 600;
  color: var(--text-dark);
  user-select: none;
}

.faq-arrow {
  color: var(--text-light);
  transition: transform 0.3s ease;
  flex-shrink: 0;
}

.faq-item.active .faq-arrow {
  transform: rotate(180deg);
  color: var(--primary);
}

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

.faq-item.active .faq-answer {
  max-height: 300px;
  padding: 0 24px 22px;
}

.faq-answer p {
  font-size: 15px;
  color: var(--text-medium);
  line-height: 1.8;
}

/* 页脚 */
.footer {
  background: var(--bg-dark);
  padding: 60px 0 30px;
  color: #94a3b8;
}

.footer-content {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 80px;
  margin-bottom: 40px;
}

.footer-logo-link {
  text-decoration: none;
  color: inherit;
  display: block;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
}

.footer-logo-icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  overflow: hidden;
  flex-shrink: 0;
}

.footer-logo-icon img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.footer-logo-title {
  font-size: 20px;
  font-weight: 700;
  color: white;
}

.footer-logo-sub {
  font-size: 13px;
  color: #64748b;
}

.footer-desc {
  font-size: 14px;
  line-height: 1.8;
  max-width: 320px;
}

.footer-qrcode {
  margin-top: 12px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.footer-qrcode img {
  width: 80px;
  height: 80px;
  border-radius: 6px;
  border: 3px solid white;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
  flex-shrink: 0;
}

.footer-qrcode p {
  font-size: 12px;
  color: #94a3b8;
  margin: 0;
  line-height: 1.5;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
}

.footer-col h4 {
  font-size: 15px;
  font-weight: 600;
  color: white;
  margin-bottom: 20px;
}

.footer-col a {
  display: block;
  font-size: 14px;
  color: #94a3b8;
  margin-bottom: 12px;
  transition: color 0.2s ease;
}

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

.footer-bottom {
  padding-top: 30px;
  border-top: 1px solid #1e293b;
  text-align: center;
  font-size: 13px;
  color: #64748b;
}

.footer-icp {
  margin-top: 8px;
  font-size: 12px;
}

.footer-icp a {
  color: #64748b;
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-icp a:hover {
  color: #94a3b8;
}

.footer-sep {
  margin: 0 12px;
  color: #334155;
}

.police-badge-icon {
  width: 14px;
  height: 14px;
  vertical-align: middle;
  margin-right: 4px;
  display: inline-block;
}

/* 子页面通用样式 */
.page-header {
  padding: 120px 0 60px;
  background: linear-gradient(180deg, #eff6ff 0%, #f8fafc 100%);
  text-align: center;
}

.page-breadcrumb {
  font-size: 14px;
  color: #64748b;
  margin-bottom: 16px;
}

.page-breadcrumb a {
  color: #3b82f6;
  text-decoration: none;
  transition: color 0.2s ease;
}

.page-breadcrumb a:hover {
  color: #2563eb;
}

.page-breadcrumb span {
  margin: 0 8px;
}

.page-title {
  font-size: 42px;
  font-weight: 800;
  color: #1e293b;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.page-subtitle {
  font-size: 18px;
  color: #64748b;
  max-width: 600px;
  margin: 0 auto;
}

.page-section {
  padding: 60px 0;
}

.page-content {
  max-width: 900px;
  margin: 0 auto;
}

.page-content h2 {
  font-size: 28px;
  font-weight: 700;
  color: #1e293b;
  margin-bottom: 20px;
  margin-top: 48px;
}

.page-content h2:first-child {
  margin-top: 0;
}

.page-content p {
  font-size: 16px;
  line-height: 1.8;
  color: #475569;
  margin-bottom: 16px;
}

.page-content ul {
  margin-bottom: 20px;
  padding-left: 24px;
}

.page-content li {
  font-size: 16px;
  line-height: 1.8;
  color: #475569;
  margin-bottom: 8px;
}

/* 关于我们页面 */
.about-intro {
  display: flex;
  gap: 60px;
  align-items: center;
  margin-bottom: 60px;
}

.about-text {
  flex: 1;
}

.about-image {
  flex: 0 0 300px;
}

.about-image-placeholder {
  width: 300px;
  height: 300px;
  background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
  border-radius: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.about-image-placeholder img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.about-values {
  margin-bottom: 60px;
}

.values-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-top: 32px;
}

.value-card {
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 16px;
  padding: 28px;
  box-shadow: 0 4px 12px -4px rgba(0, 0, 0, 0.05);
  transition: all 0.3s ease;
}

.value-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 24px -8px rgba(0, 0, 0, 0.1);
  border-color: #93c5fd;
}

.value-icon {
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
}

.value-card h3 {
  font-size: 18px;
  font-weight: 700;
  color: #1e293b;
  margin-bottom: 8px;
}

.value-card p {
  font-size: 14px;
  line-height: 1.6;
  color: #64748b;
  margin-bottom: 0;
}

.about-mission {
  margin-top: 60px;
}

.mission-card {
  background: linear-gradient(135deg, #2563eb 0%, #3b82f6 100%);
  border-radius: 24px;
  padding: 48px;
  text-align: center;
  color: white;
}

.mission-card h2 {
  color: white;
  margin-top: 0;
  margin-bottom: 24px;
}

.mission-text {
  font-size: 22px;
  font-weight: 600;
  line-height: 1.6;
  margin-bottom: 20px !important;
  color: white !important;
}

.mission-card p {
  color: rgba(255, 255, 255, 0.9);
  font-size: 16px;
  line-height: 1.8;
}

/* 联系我们页面 */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-bottom: 40px;
}

.contact-card {
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 16px;
  padding: 32px;
  transition: all 0.3s ease;
}

.contact-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 24px -8px rgba(0, 0, 0, 0.1);
  border-color: #93c5fd;
}

.contact-icon {
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

.contact-card h3 {
  font-size: 20px;
  font-weight: 700;
  color: #1e293b;
  margin-bottom: 16px;
}

.contact-card p {
  font-size: 14px;
  line-height: 1.6;
  color: #64748b;
  margin-bottom: 8px;
}

.contact-card p:last-child {
  margin-bottom: 0;
}

.qrcode-placeholder {
  width: 120px;
  height: 120px;
  background: #f1f5f9;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 16px;
  font-size: 12px;
  color: #94a3b8;
}

.contact-qr {
  margin-top: 16px;
}

.contact-qr img {
  width: 120px;
  height: 120px;
  border-radius: 12px;
  object-fit: cover;
}

/* 功能详情页面 - 页面头部 */
.page-hero {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 60px;
  align-items: center;
  margin-top: 40px;
}

.page-hero-content {
  text-align: left;
}

.page-hero-content .page-title {
  text-align: left;
  margin-bottom: 16px;
  font-size: 44px;
}

.page-hero-content .page-subtitle {
  text-align: left;
  margin: 0 0 24px 0;
  max-width: none;
  font-size: 17px;
}

.page-hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 32px;
}

.page-tag {
  padding: 6px 16px;
  background: rgba(59, 130, 246, 0.1);
  color: #3b82f6;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 500;
}

.page-tag-dark {
  background: rgba(255, 255, 255, 0.15);
  color: white;
}

.page-hero-buttons {
  display: flex;
  gap: 16px;
}

.page-hero-image {
  text-align: center;
}

.page-hero-image img {
  max-width: 400px;
  width: 100%;
  height: auto;
  border-radius: 24px;
  box-shadow: 0 20px 60px -20px rgba(59, 130, 246, 0.3);
}

.page-header-dark {
  background: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #0f172a 100%);
  color: white;
  position: relative;
  overflow: hidden;
}

.page-header-dark::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: 
    radial-gradient(circle at 80% 50%, rgba(59, 130, 246, 0.15) 0%, transparent 50%),
    radial-gradient(circle at 20% 80%, rgba(6, 182, 212, 0.1) 0%, transparent 40%);
  pointer-events: none;
}

.page-header-dark .page-title {
  color: white;
}

.page-header-dark .page-subtitle {
  color: rgba(255, 255, 255, 0.7);
}

.page-header-dark .page-breadcrumb a {
  color: rgba(255, 255, 255, 0.6);
}

.page-header-dark .page-breadcrumb span {
  color: rgba(255, 255, 255, 0.4);
}

/* 功能详情页面 - 核心价值 */
.value-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-top: 32px;
}

.value-card {
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 16px;
  padding: 28px 24px;
  transition: all 0.3s ease;
  text-align: center;
}

.value-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px -8px rgba(0, 0, 0, 0.1);
  border-color: #3b82f6;
}

.value-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 20px;
  background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.value-icon-red {
  background: linear-gradient(135deg, #fef2f2 0%, #fee2e2 100%);
}

.value-card h3 {
  font-size: 18px;
  font-weight: 700;
  color: #1e293b;
  margin-bottom: 12px;
}

.value-card p {
  font-size: 14px;
  line-height: 1.7;
  color: #64748b;
}

/* 功能详情页面 - 功能详情 */
.feature-detail-list {
  margin-top: 32px;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.feature-detail-card {
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 16px;
  padding: 32px 28px;
  box-shadow: 0 4px 12px -4px rgba(0, 0, 0, 0.05);
  transition: all 0.3s ease;
}

.feature-detail-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px -8px rgba(0, 0, 0, 0.1);
  border-color: #3b82f6;
}

.feature-detail-card-icon {
  width: 56px;
  height: 56px;
  margin-bottom: 20px;
  background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.feature-detail-card h3 {
  font-size: 20px;
  font-weight: 700;
  color: #1e293b;
  margin-bottom: 12px;
}

.feature-detail-card p {
  font-size: 14px;
  line-height: 1.7;
  color: #64748b;
  margin-bottom: 16px;
}

.feature-detail-points {
  list-style: none;
  padding: 0;
  margin: 0;
}

.feature-detail-points li {
  position: relative;
  padding-left: 24px;
  margin-bottom: 8px;
  font-size: 13px;
  color: #475569;
  line-height: 1.6;
}

.feature-detail-points li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 5px;
  width: 16px;
  height: 16px;
  background: linear-gradient(135deg, #3b82f6 0%, #06b6d4 100%);
  border-radius: 50%;
  mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='3'%3E%3Cpolyline points='20 6 9 17 4 12'/%3E%3C/svg%3E") center/10px no-repeat;
  -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='3'%3E%3Cpolyline points='20 6 9 17 4 12'/%3E%3C/svg%3E") center/10px no-repeat;
}

/* 功能详情页面 - 适用场景 */
.scene-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-top: 32px;
}

.scene-card {
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 16px;
  padding: 28px 24px;
  box-shadow: 0 4px 12px -4px rgba(0, 0, 0, 0.05);
  transition: all 0.3s ease;
}

.scene-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px -8px rgba(0, 0, 0, 0.1);
}

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

.scene-card h3 {
  font-size: 18px;
  font-weight: 700;
  color: #1e293b;
  margin-bottom: 12px;
}

.scene-card p {
  font-size: 14px;
  line-height: 1.7;
  color: #64748b;
}

/* 功能详情页面 - 对比表格 */
.compare-table {
  margin-top: 40px;
  background: white;
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 4px 20px -8px rgba(0, 0, 0, 0.08);
}

.compare-row {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  border-bottom: 1px solid #f1f5f9;
}

.compare-row:last-child {
  border-bottom: none;
}

.compare-col {
  padding: 20px 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 15px;
  color: #475569;
}

.compare-header .compare-col {
  font-weight: 700;
  font-size: 16px;
  color: #1e293b;
  background: #f8fafc;
}

.compare-col-bad {
  color: #ef4444;
}

.compare-col-good {
  color: #10b981;
  font-weight: 600;
}

.compare-header .compare-col-bad {
  color: #ef4444;
  background: #fef2f2;
}

.compare-header .compare-col-good {
  color: #059669;
  background: #f0fdf4;
}

/* 功能详情页面 - CTA区域 */
.cta-section {
  padding: 80px 0;
  background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
  text-align: center;
}

.cta-section-dark {
  background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
  color: white;
}

.cta-content h2 {
  font-size: 36px;
  font-weight: 800;
  margin-bottom: 16px;
  color: #1e293b;
}

.cta-section-dark .cta-content h2 {
  color: white;
}

.cta-content p {
  font-size: 18px;
  color: #64748b;
  margin-bottom: 32px;
}

.cta-section-dark .cta-content p {
  color: rgba(255, 255, 255, 0.7);
}

.btn-white {
  background: white;
  color: #3b82f6;
  border: 2px solid white;
}

.btn-white:hover {
  background: #f8fafc;
  color: #2563eb;
}

/* 响应式 */
@media (max-width: 1200px) {
  .nav-container {
    padding: 0 24px;
  }

  .nav-menu {
    display: none;
  }

  .nav-download-btn {
    padding: 10px 18px;
    font-size: 14px;
  }

  .container {
    padding: 0 24px;
  }

  .hero-container {
    gap: 32px;
  }

  .hero-title {
    font-size: 48px;
  }

  .hero-image {
    height: 600px;
  }

  .hero-phone-parent {
    width: 88%;
    left: -5%;
    top: 25px;
  }

  .hero-phone-child {
    width: 73%;
    right: -5%;
    top: 95px;
  }

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

  .feature-grid {
    grid-template-columns: repeat(4, 1fr);
  }

  .section-title {
    font-size: 32px;
  }

  /* 窗口非最大化（<1200px）时，下载卡片按钮再缩小一圈，避免挤压到换行 */
  .download-buttons .btn-download {
    padding: 12px 14px;
    font-size: 14px;
  }
  .download-buttons {
    gap: 10px;
  }
}

@media (max-width: 1024px) {
  .hero-container {
    grid-template-columns: 1.1fr 0.9fr;
    gap: 24px;
  }

  .hero-title {
    font-size: 40px;
  }

  .hero-image {
    height: 520px;
  }

  .hero-phone-parent {
    width: 82%;
    left: -3%;
    top: 15px;
  }

  .hero-phone-child {
    width: 68%;
    right: -3%;
    top: 75px;
  }

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

  .hero-features {
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
  }

  .hero-feature-item {
    padding: 12px 14px;
  }

  .hero-feature-title {
    font-size: 14px;
  }

  .hero-feature-sub {
    font-size: 12px;
  }

  .feature-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .security .container {
    grid-template-columns: 1.1fr 0.9fr;
    gap: 32px;
  }

  .security-title {
    font-size: 36px;
  }

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

  .download-grid {
    gap: 20px;
  }

  .download-card {
    padding: 24px 20px;
  }

  .guide-steps {
    gap: 16px;
  }

  .guide-step {
    padding: 24px 20px;
  }

  .footer-content {
    gap: 32px;
  }

  .features,
  .security,
  .download,
  .guide,
  .faq {
    padding: 50px 0;
  }
}

@media (max-width: 768px) {
  .nav-container {
    padding: 0 20px;
  }

  .nav-download-btn {
    padding: 10px 16px;
    font-size: 14px;
  }

  .hero {
    padding: 90px 0 50px;
  }

  .hero-container {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 40px;
  }

  .hero-title {
    font-size: 36px;
  }

  .hero-image {
    height: 420px;
    max-width: 420px;
    margin: 0 auto;
  }

  .hero-phone-parent {
    width: 80%;
    left: -2%;
    top: 10px;
  }

  .hero-phone-child {
    width: 65%;
    right: -2%;
    top: 55px;
  }

  .hero-desc {
    margin: 0 auto 28px;
  }

  .hero-features {
    grid-template-columns: 1fr 1fr;
    max-width: 400px;
    margin: 0 auto 28px;
  }

  .hero-buttons {
    justify-content: center;
  }

  .hero-badge {
    justify-content: center;
  }

  .hero-tags {
    justify-content: center;
  }

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

  .section-title {
    font-size: 28px;
  }

  .section-subtitle {
    font-size: 15px;
  }

  .security .container {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 40px;
  }

  .security-title {
    font-size: 28px;
  }

  .security-desc {
    margin: 0 auto 32px;
  }

  .security-grid {
    grid-template-columns: 1fr;
    max-width: 400px;
    margin: 0 auto;
  }

  .download-grid {
    grid-template-columns: 1fr;
    max-width: 420px;
    margin: 0 auto;
  }

  .guide-steps {
    flex-direction: column;
  }

  .step-arrow {
    transform: rotate(90deg);
  }

  .footer-links {
    display: none;
  }

  .footer-brand {
    display: none;
  }

  .footer-content {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .footer-bottom {
    text-align: center;
    padding: 16px 0;
    border-top: 1px solid #eee;
  }

  .footer-bottom p {
    margin: 4px 0;
    font-size: 11px;
    color: #999;
  }

  .footer-icp {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
  }

  .footer-sep {
    display: none;
  }

  .police-badge-icon {
    width: 12px;
    height: 12px;
    vertical-align: middle;
    margin-right: 3px;
  }

  /* 移动端按钮优化 */
  .btn {
    min-height: 48px;
    font-size: 16px;
    padding: 14px 24px;
  }

  /* 移动端卡片优化 */
  .feature-card {
    padding: 20px 14px;
  }

  .feature-icon {
    width: 48px;
    height: 48px;
    margin-bottom: 10px;
  }

  .feature-card-title {
    font-size: 15px;
  }

  .feature-card-desc {
    font-size: 12px;
    line-height: 1.5;
  }

  /* 移动端下载卡片优化 */
  .download-card {
    padding: 24px 20px;
  }

  .download-qr {
    flex-direction: column;
    gap: 16px;
    text-align: center;
  }

  .qr-image {
    margin: 0 auto;
    width: 120px;
    height: 120px;
  }

  .download-title {
    font-size: 20px;
  }

  .btn-download {
    padding: 14px 20px;
    font-size: 15px;
  }

  /* 移动端区块间距优化 */
  .features,
  .security,
  .download,
  .guide,
  .faq {
    padding: 40px 0;
  }

  /* 移动端子页面优化 */
  .page-header {
    padding: 100px 0 40px;
  }

  .page-title {
    font-size: 32px;
  }

  .page-section {
    padding: 50px 0;
  }

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

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

  .about-intro {
    flex-direction: column;
    gap: 40px;
  }

  .about-image {
    order: -1;
  }

  .about-image-placeholder {
    width: 100%;
    max-width: 300px;
    height: 250px;
    margin: 0 auto;
  }
}

@media (max-width: 480px) {
  .nav-container {
    padding: 0 16px;
  }

  .nav-logo .logo-subtitle {
    display: none;
  }

  .nav-download-btn {
    padding: 8px 12px;
    font-size: 13px;
  }

  .nav-download-btn svg {
    display: none;
  }

  .hero-title {
    font-size: 28px;
  }

  .hero-image {
    height: 340px;
    max-width: 340px;
  }

  .hero-phone-parent {
    width: 75%;
    left: 0;
    top: 5px;
  }

  .hero-phone-child {
    width: 60%;
    right: 0;
    top: 35px;
  }

  .hero-desc {
    font-size: 14px;
  }

  .hero-buttons {
    flex-direction: column;
  }

  .btn {
    width: 100%;
    min-height: 52px;
    font-size: 16px;
  }

  .hero-features {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
  }

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

  .section-title {
    font-size: 24px;
  }

  .section-subtitle {
    font-size: 14px;
  }

  .security-title {
    font-size: 24px;
  }

  .security-item-title {
    font-size: 16px;
  }

  .security-item-desc {
    font-size: 13px;
  }

  .download-title {
    font-size: 18px;
  }

  .download-subtitle {
    font-size: 13px;
  }

  .guide-step {
    padding: 20px 16px;
  }

  .step-number {
    width: 40px;
    height: 40px;
    font-size: 20px;
  }

  .step-title {
    font-size: 15px;
  }

  .step-desc {
    font-size: 12px;
  }

  .faq-question {
    font-size: 15px;
    padding: 16px 0;
  }

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

  .footer-links {
    display: none;
  }

  .footer-brand {
    display: none;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 8px;
    text-align: center;
  }

  /* 小屏幕子页面优化 */
  .page-title {
    font-size: 28px;
  }

  .page-subtitle {
    font-size: 14px;
  }

  .page-content h2 {
    font-size: 22px;
  }

  .page-content p,
  .page-content li {
    font-size: 15px;
  }

  .value-card {
    padding: 20px;
  }

  .value-icon {
    width: 48px;
    height: 48px;
  }

  .value-card h3 {
    font-size: 16px;
  }

  .value-card p {
    font-size: 13px;
  }

  .contact-card {
    padding: 24px 20px;
  }

  .mission-card {
    padding: 32px 24px;
  }

  .mission-text {
    font-size: 18px !important;
  }
}

/* 滚动入场动画 */
.fade-in-up {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in-up.visible {
  opacity: 1;
  transform: translateY(0);
}