/* ===================================
   全局样式和变量定义
   =================================== */

:root {
  /* 颜色变量 */
  --primary-color: #FF6B35;
  --primary-hover: #E55A2B;
  --secondary-color: #4A90E2;
  --background-color: #FFFFFF;
  --background-secondary: #F7F9FC;
  --text-primary: #333333;
  --text-secondary: #666666;
  --border-color: #E5E7EB;
  --shadow-light: 0 2px 12px rgba(0, 0, 0, 0.08);
  --shadow-medium: 0 4px 20px rgba(0, 0, 0, 0.12);
  --shadow-heavy: 0 8px 30px rgba(0, 0, 0, 0.15);
  
  /* 字体 */
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 
                 'Microsoft YaHei', 'Helvetica Neue', Helvetica, Arial, sans-serif;
  
  /* 字号 */
  --font-size-h1: 48px;
  --font-size-h2: 36px;
  --font-size-h3: 28px;
  --font-size-body: 16px;
  --font-size-small: 14px;
  
  /* 间距 */
  --spacing-xs: 8px;
  --spacing-sm: 16px;
  --spacing-md: 24px;
  --spacing-lg: 32px;
  --spacing-xl: 48px;
  --spacing-xxl: 64px;
  
  /* 圆角 */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  
  /* 过渡 */
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
  
  /* 容器宽度 */
  --container-width: 1200px;
}

/* ===================================
   重置样式
   =================================== */

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-body);
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--background-color);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

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

ul, ol {
  list-style: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  outline: none;
  transition: var(--transition-fast);
}

input, textarea, select {
  font-family: inherit;
  font-size: inherit;
  outline: none;
  border: 1px solid var(--border-color);
  transition: var(--transition-fast);
}

input:focus, textarea:focus, select:focus {
  border-color: var(--primary-color);
}

/* ===================================
   通用工具类
   =================================== */

.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.section {
  padding: var(--spacing-xxl) 0;
}

.section-title {
  font-size: var(--font-size-h2);
  font-weight: 700;
  text-align: center;
  margin-bottom: var(--spacing-lg);
  color: var(--text-primary);
}

.section-subtitle {
  font-size: var(--font-size-body);
  text-align: center;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xl);
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.text-center {
  text-align: center;
}

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

.text-secondary {
  color: var(--text-secondary);
}

/* ===================================
   导航栏样式
   =================================== */

.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-light);
  z-index: 1000;
  transition: var(--transition-normal);
}

.navbar.scrolled {
  box-shadow: var(--shadow-medium);
}

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

.navbar-logo {
  display: flex;
  align-items: center;
  font-size: 24px;
  font-weight: 700;
  color: var(--primary-color);
}

.navbar-logo img {
  height: 40px;
  margin-right: var(--spacing-sm);
}

.navbar-menu {
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
}

.navbar-menu a {
  font-size: var(--font-size-body);
  font-weight: 500;
  color: var(--text-primary);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  transition: var(--transition-fast);
}

.navbar-menu a:hover,
.navbar-menu a.active {
  color: var(--primary-color);
  background-color: rgba(255, 107, 53, 0.1);
}

.navbar-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  padding: var(--spacing-xs);
}

.navbar-toggle span {
  display: block;
  width: 25px;
  height: 3px;
  background-color: var(--text-primary);
  border-radius: 2px;
  transition: var(--transition-fast);
}

/* ===================================
   按钮样式
   =================================== */

.btn {
  display: inline-block;
  padding: 12px 32px;
  font-size: var(--font-size-body);
  font-weight: 600;
  text-align: center;
  border-radius: var(--radius-md);
  transition: var(--transition-fast);
  cursor: pointer;
  border: 2px solid transparent;
}

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

.btn-primary:hover {
  background-color: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-medium);
  color: white;
}

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

.btn-secondary:hover {
  background-color: var(--primary-color);
  color: white;
  transform: translateY(-2px);
  box-shadow: var(--shadow-medium);
}

.btn-large {
  padding: 16px 48px;
  font-size: 18px;
}

.btn-group {
  display: flex;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
}

/* ===================================
   卡片样式
   =================================== */

.card {
  background-color: white;
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  box-shadow: var(--shadow-light);
  transition: var(--transition-normal);
}

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

.card-icon {
  width: 64px;
  height: 64px;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 32px;
  margin-bottom: var(--spacing-md);
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
}

.card-title {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: var(--spacing-sm);
  color: var(--text-primary);
}

.card-description {
  font-size: var(--font-size-body);
  color: var(--text-secondary);
  line-height: 1.8;
}

/* ===================================
   网格布局
   =================================== */

.grid {
  display: grid;
  gap: var(--spacing-lg);
}

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

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

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

/* ===================================
   Hero 区域样式
   =================================== */

.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  background: linear-gradient(135deg, #F7F9FC 0%, #FFFFFF 100%);
  padding-top: 70px;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  width: 50%;
  height: 100%;
  background: linear-gradient(135deg, rgba(255, 107, 53, 0.05), rgba(74, 144, 226, 0.05));
  border-radius: 0 0 0 50%;
  z-index: 0;
}

.hero .container {
  position: relative;
  z-index: 1;
}

.hero-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-xxl);
  align-items: center;
}

.hero-text h1 {
  font-size: var(--font-size-h1);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

.hero-text h1 .highlight {
  color: var(--primary-color);
}

.hero-text p {
  font-size: 18px;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-lg);
  line-height: 1.8;
}

.hero-image {
  position: relative;
}

.hero-image img {
  width: 100%;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-heavy);
}

/* ===================================
   功能展示区域
   =================================== */

.features {
  background-color: white;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-lg);
}

/* ===================================
   平台支持区域
   =================================== */

.platforms {
  background-color: var(--background-secondary);
}

.platforms-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: var(--spacing-md);
  margin-top: var(--spacing-xl);
}

.platform-item {
  background-color: white;
  padding: var(--spacing-md);
  border-radius: var(--radius-lg);
  text-align: center;
  transition: var(--transition-normal);
  box-shadow: var(--shadow-light);
}

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

.platform-item img {
  width: 60px;
  height: 60px;
  margin: 0 auto var(--spacing-sm);
}

.platform-item span {
  display: block;
  font-size: var(--font-size-small);
  color: var(--text-secondary);
  font-weight: 500;
}

/* ===================================
   页脚样式
   =================================== */

.footer {
  background-color: #2C3E50;
  color: white;
  padding: var(--spacing-xxl) 0 var(--spacing-lg);
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-lg);
}

.footer-section h3 {
  font-size: 18px;
  margin-bottom: var(--spacing-md);
  color: white;
}

.footer-section p,
.footer-section a {
  color: rgba(255, 255, 255, 0.8);
  font-size: var(--font-size-small);
  line-height: 2;
}

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

.footer-links {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: var(--spacing-md);
  text-align: center;
  color: rgba(255, 255, 255, 0.6);
  font-size: var(--font-size-small);
}

/* ===================================
   表单样式
   =================================== */

.form-group {
  margin-bottom: var(--spacing-md);
}

.form-label {
  display: block;
  margin-bottom: var(--spacing-xs);
  font-weight: 600;
  color: var(--text-primary);
}

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  font-size: var(--font-size-body);
  transition: var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(255, 107, 53, 0.1);
}

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

.form-error {
  color: #E74C3C;
  font-size: var(--font-size-small);
  margin-top: var(--spacing-xs);
}

.form-success {
  color: #27AE60;
  font-size: var(--font-size-small);
  margin-top: var(--spacing-xs);
}

/* ===================================
   加载动画
   =================================== */

.loading {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top-color: white;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ===================================
   滚动动画
   =================================== */

.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* ===================================
   响应式设计 - 平板
   =================================== */

@media (max-width: 1023px) {
  :root {
    --font-size-h1: 36px;
    --font-size-h2: 28px;
    --font-size-h3: 24px;
  }
  
  .grid-3,
  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .hero-content {
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
  }
  
  .hero-image {
    order: -1;
  }
  
  .footer-content {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* ===================================
   响应式设计 - 手机
   =================================== */

@media (max-width: 767px) {
  :root {
    --font-size-h1: 32px;
    --font-size-h2: 24px;
    --font-size-h3: 20px;
    --font-size-body: 14px;
    --spacing-xxl: 48px;
  }
  
  .section {
    padding: var(--spacing-xl) 0;
  }
  
  .navbar .container {
    height: 60px;
  }
  
  .navbar-menu {
    position: fixed;
    top: 60px;
    left: 0;
    right: 0;
    background-color: white;
    flex-direction: column;
    padding: var(--spacing-md);
    box-shadow: var(--shadow-medium);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition-normal);
  }
  
  .navbar-menu.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }
  
  .navbar-toggle {
    display: flex;
  }
  
  .navbar-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }
  
  .navbar-toggle.active span:nth-child(2) {
    opacity: 0;
  }
  
  .navbar-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
  }
  
  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }
  
  .features-grid {
    grid-template-columns: 1fr;
  }
  
  .hero {
    min-height: auto;
    padding: calc(60px + var(--spacing-xl)) 0 var(--spacing-xl);
  }
  
  .hero-text h1 {
    font-size: 28px;
  }
  
  .hero-text p {
    font-size: 16px;
  }
  
  .btn-group {
    flex-direction: column;
  }
  
  .btn {
    width: 100%;
  }
  
  .footer-content {
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
  }
  
  .platforms-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* ===================================
   下载区域样式
   =================================== */

.downloads-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
  margin-top: var(--spacing-xl);
}

.download-card {
  background: white;
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  box-shadow: var(--shadow-light);
  transition: var(--transition-normal);
  border: 1px solid var(--border-color);
}

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

.download-card-header {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.download-card-icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  border-radius: var(--radius-md);
  color: white;
  font-size: 24px;
}

.download-card-title {
  flex: 1;
}

.download-card-title h3 {
  font-size: 20px;
  margin: 0 0 4px 0;
  color: var(--text-primary);
}

.download-card-title .platform {
  font-size: 14px;
  color: var(--text-secondary);
}

.download-card-info {
  margin-bottom: var(--spacing-md);
}

.download-info-item {
  display: flex;
  justify-content: space-between;
  padding: 8px 0;
  border-bottom: 1px solid var(--border-color);
}

.download-info-item:last-child {
  border-bottom: none;
}

.download-info-label {
  color: var(--text-secondary);
  font-size: 14px;
}

.download-info-value {
  color: var(--text-primary);
  font-weight: 500;
  font-size: 14px;
}

.download-card-notes {
  margin-bottom: var(--spacing-md);
  padding: var(--spacing-sm);
  background: var(--background-secondary);
  border-radius: var(--radius-md);
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
}

.download-card-notes h4 {
  font-size: 14px;
  margin: 0 0 8px 0;
  color: var(--text-primary);
}

.download-card-button {
  width: 100%;
}

@media (max-width: 768px) {
  .downloads-grid {
    grid-template-columns: 1fr;
  }
}

/* ===================================
   打印样式
   =================================== */

@media print {
  .navbar,
  .footer,
  .btn {
    display: none;
  }
}