:root {
  --brand-primary: #42affa; /* 主要品牌色 - 蓝色 */
  --brand-primary-light: #70c1ff; /* 主要品牌色浅色 */
  --brand-primary-dark: #1a8fe0; /* 主要品牌色深色 */
  --brand-primary-darker: #0d6fb3; /* 主要品牌色更深色 */
  --brand-secondary: #ff6b6b; /* 次要品牌色 - 红色 */
  --brand-accent: #6bff99; /* 强调色 - 绿色 */
  --brand-dark: #121212; /* 主要深色背景 */
  --brand-darker: #0a0a0a; /* 更深的背景色 */
  --brand-darkest: #050505; /* 最深背景色 */
  --brand-light: #f8f9fa; /* 浅色文字 */
  --brand-text: #ffffff; /* 主要文字色 */
  --brand-text-secondary: #cccccc; /* 次要文字色 */
  --brand-text-muted: #aaaaaa; /* 弱化文字色 */
  --card-bg: rgba(30, 30, 30, 0.85); /* 卡片背景色 */
  --card-border: rgba(66, 175, 250, 0.25); /* 卡片边框色 */
  --card-border-hover: rgba(66, 175, 250, 0.5); /* 卡片悬停边框色 */
  --section-bg: rgba(20, 20, 20, 0.9); /* 区域背景色 */
  --gradient-primary: linear-gradient(135deg, var(--brand-primary), var(--brand-primary-dark)); /* 主要渐变 */
  --gradient-secondary: linear-gradient(135deg, var(--brand-secondary), var(--brand-accent)); /* 次要渐变 */
  --gradient-button: linear-gradient(135deg, var(--brand-primary-light), var(--brand-primary)); /* 按钮渐变 */
  --gradient-button-hover: linear-gradient(135deg, var(--brand-primary), var(--brand-primary-darker)); /* 按钮悬停渐变 */
  --shadow-default: 0 10px 30px rgba(0, 0, 0, 0.3);
  --shadow-hover: 0 15px 35px rgba(0, 0, 0, 0.4);
  --border-radius-default: 16px;
  --border-radius-button: 30px;
  --transition-default: all 0.3s ease;
  --transition-bounce: all 0.6s cubic-bezier(0.175, 0.885, 0.32, 1.275); /* 弹跳效果 */
}

/* 浅色主题变量 - 使用body选择器而不是:root来避免被reveal.js覆盖 */
body.light-theme {
  --brand-primary: #42affa;
  --brand-primary-light: #70c1ff;
  --brand-primary-dark: #1a8fe0;
  --brand-primary-darker: #0d6fb3;
  --brand-secondary: #ff6b6b;
  --brand-accent: #6bff99;
  --brand-dark: #f8f9fa;
  --brand-darker: #e9ecef;
  --brand-darkest: #dee2e6;
  --brand-light: #121212;
  --brand-text: #343a40;
  --brand-text-secondary: #495057;
  --brand-text-muted: #6c757d;
  --card-bg: rgba(255, 255, 255, 0.9);
  --card-border: rgba(66, 175, 250, 0.3);
  --card-border-hover: rgba(66, 175, 250, 0.6);
  --section-bg: rgba(248, 249, 250, 0.95);
  --shadow-default: 0 10px 30px rgba(0, 0, 0, 0.1);
  --shadow-hover: 0 15px 35px rgba(0, 0, 0, 0.15);
}

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

body {
  font-family: 'Source Sans Pro', 'Helvetica Neue', Arial, sans-serif;
  background: var(--brand-dark);
  color: var(--brand-text);
  margin: 0;
  padding: 0;
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.6;
  letter-spacing: 0.02em; /* 增加轻微字间距提升可读性 */
}

/* 覆盖reveal.js的背景设置 */
body.light-theme .reveal-viewport,
.reveal-viewport {
  background: var(--brand-dark) !important;
  background-color: var(--brand-dark) !important;
  background-image: none !important;
}

/* 预加载器样式 */
.preloader {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--brand-darker);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 9999;
  transition: opacity 0.5s ease, visibility 0.5s ease;
}

.preloader.hidden {
  opacity: 0;
  visibility: hidden;
}

.spinner {
  width: 50px;
  height: 50px;
  border: 5px solid rgba(66, 175, 250, 0.3);
  border-top: 5px solid var(--brand-primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

/* 导航栏 */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  padding: 1rem 5%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  z-index: 1000;
  background: rgba(15, 15, 15, 0.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(66, 175, 250, 0.1);
  transition: all 0.3s ease;
}

.navbar.scrolled {
  padding: 0.5rem 5%;
  background: rgba(15, 15, 15, 0.95);
  box-shadow: 0 5px 20px rgba(0, 0, 0, 0.2);
}

/* 浅色主题下的导航栏样式 */
body.light-theme .navbar {
  background: rgba(248, 249, 250, 0.9);
  border-bottom: 1px solid rgba(66, 175, 250, 0.2);
}

body.light-theme .navbar.scrolled {
  background: rgba(248, 249, 250, 0.95);
  box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
}

.logo-container {
  display: flex;
  align-items: center;
}

.logo-container img {
  height: 40px;
  margin-right: 10px;
  transition: transform 0.3s ease;
}

.logo-container img:hover {
  transform: scale(1.05);
}

.logo-text {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--brand-text);
  text-decoration: none;
  letter-spacing: 0.5px;
}

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

.nav-links {
  display: flex;
  gap: 2rem;
}

.nav-links a {
  color: var(--brand-text);
  text-decoration: none;
  font-weight: 500;
  transition: var(--transition-default);
  position: relative;
  padding: 0.5rem 0;
}

.nav-links a:hover {
  color: var(--brand-primary);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--brand-primary);
  transition: width 0.3s ease;
}

.nav-links a:hover::after {
  width: 100%;
}

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

.landing-container {
  max-width: 100%;
  margin: 0;
  padding: 0;
}

/* 英雄区域样式 */
.hero-section {
  position: relative;
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  overflow: hidden;
  padding-top: 80px;
}

.parallax-layer {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

.parallax-layer.background {
  background-image: url(../img/bg16.jpg);
  background-size: cover;
  background-position: center center;
  background-repeat: no-repeat;
  position: relative;
  animation: zoomEffect 20s infinite alternate;
}

@keyframes zoomEffect {
  0% {
    transform: scale(1);
  }
  100% {
    transform: scale(1.1);
  }
}

.parallax-layer.background::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, rgba(15, 15, 15, 0.9) 0%, rgba(25, 25, 25, 0.7) 50%, rgba(66, 175, 250, 0.2) 100%);
}

/* 浅色主题下的英雄区域背景 */
body.light-theme .parallax-layer.background::after {
  background: linear-gradient(135deg, rgba(248, 249, 250, 0.3) 0%, rgba(233, 236, 239, 0.2) 50%, rgba(66, 175, 250, 0.15) 100%);
}

.parallax-layer.foreground {
  z-index: 2;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  background: rgba(0, 0, 0, 0.3);
}

/* 浅色主题下的前景层 */
body.light-theme .parallax-layer.foreground {
  background: rgba(255, 255, 255, 0.2);
}

.hero-content {
  max-width: 800px;
  padding: 2rem;
  z-index: 3;
  animation: fadeIn 1s ease;
}

.logo {
  width: 150px;
  height: auto;
  margin-bottom: 1.5rem;
  animation: fadeInDown 1s ease;
  filter: drop-shadow(0 0 10px rgba(66, 175, 250, 0.5));
  transition: transform 0.5s ease;
}

.logo:hover {
  transform: scale(1.05);
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 800;
  margin-bottom: 1rem;
  text-transform: uppercase;
  letter-spacing: 2px;
  background: linear-gradient(90deg, #fff, var(--brand-primary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  animation: fadeInUp 1s ease;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
  line-height: 1.2;
}

.subtitle {
  font-size: 1.5rem;
  margin-bottom: 2rem;
  color: var(--brand-text-secondary);
  animation: fadeInUp 1s ease 0.2s both;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
  line-height: 1.5;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
  justify-content: center;
  margin-top: 2rem;
  animation: fadeInUp 1s ease 0.4s both;
}

/* 产品优势区域 */
.advantages-section {
  padding: 6rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
  text-align: center;
  background: var(--section-bg);
  position: relative;
  overflow: hidden;
}

.advantages-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at center, rgba(66, 175, 250, 0.1) 0%, transparent 70%);
}

.advantages-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
  position: relative;
  z-index: 2;
}

.advantage-card {
  background: var(--card-bg);
  border-radius: var(--border-radius-default);
  padding: 2rem;
  border: 1px solid var(--card-border);
  transition: var(--transition-bounce);
  text-align: center;
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-default);
  position: relative;
  overflow: hidden;
}

.advantage-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: var(--gradient-primary);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.3s ease;
}

.advantage-card:hover::before {
  transform: scaleX(1);
}

.advantage-card:hover {
  transform: translateY(-10px) scale(1.02);
  border-color: var(--card-border-hover);
  box-shadow: var(--shadow-hover);
}

.advantage-icon {
  font-size: 2.5rem;
  color: var(--brand-primary);
  margin-bottom: 1.5rem;
  background: rgba(66, 175, 250, 0.1);
  width: 80px;
  height: 80px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  margin: 0 auto 1.5rem;
  transition: var(--transition-default);
}

.advantage-card:hover .advantage-icon {
  transform: scale(1.1);
  background: rgba(66, 175, 250, 0.2);
  box-shadow: 0 0 20px rgba(66, 175, 250, 0.3);
}

.advantage-card h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--brand-primary);
}

.advantage-card p {
  color: var(--brand-text-secondary);
  line-height: 1.6;
}

/* 功能区域样式 */
.features-section {
  padding: 6rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.features-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at center, rgba(255, 107, 107, 0.1) 0%, transparent 70%);
}

.section-title {
  margin-bottom: 4rem;
  position: relative;
  z-index: 2;
}

.section-title h2 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  color: var(--brand-primary);
  position: relative;
  display: inline-block;
}

.section-title h2::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 80px;
  height: 4px;
  background: var(--brand-primary);
  border-radius: 2px;
}

.section-title p {
  font-size: 1.2rem;
  color: var(--brand-text-muted);
  margin-top: 2rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.6;
}

.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin: 3rem 0;
  position: relative;
  z-index: 2;
}

.feature-card {
  background: var(--card-bg);
  border-radius: var(--border-radius-default);
  padding: 2.5rem 2rem;
  transition: var(--transition-bounce);
  border: 1px solid var(--card-border);
  box-shadow: var(--shadow-default);
  text-align: center;
  backdrop-filter: blur(10px);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity 0.3s ease;
  z-index: -1;
}

.feature-card:hover::before {
  opacity: 0.1;
}

.feature-card:hover {
  transform: translateY(-10px) scale(1.02);
  box-shadow: var(--shadow-hover);
  border-color: var(--card-border-hover);
}

.feature-icon {
  margin-bottom: 1.5rem;
  transition: transform 0.3s ease;
}

.feature-card:hover .feature-icon {
  transform: scale(1.1);
}

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

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

/* 使用步骤区域样式 */
.how-it-works-section {
  padding: 6rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
  text-align: center;
  background: var(--section-bg);
  position: relative;
  overflow: hidden;
}

.how-it-works-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at center, rgba(107, 255, 153, 0.1) 0%, transparent 70%);
}

.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  margin: 3rem 0;
  position: relative;
  z-index: 2;
}

.step {
  background: rgba(30, 30, 30, 0.8);
  border-radius: var(--border-radius-default);
  padding: 2.5rem 2rem;
  transition: var(--transition-bounce);
  border: 1px solid rgba(66, 175, 250, 0.2);
  position: relative;
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-default);
}

/* 浅色主题下的步骤容器样式 */
body.light-theme .step {
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid rgba(66, 175, 250, 0.3);
}

.step-number {
  position: absolute;
  top: -20px;
  left: 50%;
  transform: translateX(-50%);
  width: 40px;
  height: 40px;
  background: var(--brand-primary);
  color: var(--brand-dark);
  border-radius: 50%;
  display: flex;
  justify-content: center;
  align-items: center;
  font-weight: bold;
  font-size: 1.2rem;
  box-shadow: 0 4px 10px rgba(66, 175, 250, 0.4);
}

.step h3 {
  font-size: 1.5rem;
  margin: 1rem 0 1rem;
  color: var(--brand-primary);
}

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

/* 用户评价区域样式 */
.testimonials-section {
  padding: 6rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.testimonials-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at center, rgba(255, 107, 107, 0.1) 0%, transparent 70%);
}

.testimonials {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  gap: 2rem;
  margin: 3rem 0;
  position: relative;
  z-index: 2;
}

.testimonial {
  background: rgba(30, 30, 30, 0.8);
  border-radius: var(--border-radius-default);
  padding: 2.5rem 2rem;
  transition: var(--transition-bounce);
  border: 1px solid rgba(66, 175, 250, 0.2);
  font-style: italic;
  position: relative;
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-default);
}

/* 浅色主题下的用户评价容器样式 */
body.light-theme .testimonial {
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid rgba(66, 175, 250, 0.3);
}

.testimonial::before {
  position: absolute;
  top: 10px;
  left: 20px;
  font-size: 5rem;
  color: rgba(66, 175, 250, 0.2);
  font-family: Georgia, serif;
}

.author {
  text-align: right;
  margin-top: 1.5rem;
  color: var(--brand-primary);
  font-style: normal;
  font-weight: 600;
}

/* 页脚样式 */
.footer {
  margin: 2rem 0;
  color: var(--brand-text-muted);
  font-size: 0.9rem;
  text-align: center;
  /*padding: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);*/
}

/* 浅色主题下的页脚样式 */
body.light-theme .footer {
  /*border-top: 1px solid rgba(0, 0, 0, 0.1);*/
}

/* CTA区域样式 */
.cta-section {
  padding: 6rem 2rem;
  text-align: center;
  background: linear-gradient(135deg, var(--brand-darkest) 0%, var(--brand-dark) 100%);
  position: relative;
  overflow: hidden;
}

.cta-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at center, rgba(66, 175, 250, 0.15) 0%, transparent 70%);
}

.cta-section::after {
  content: '';
  position: absolute;
  top: -150%;
  left: -150%;
  width: 400%;
  height: 400%;
  background: conic-gradient(
    transparent,
    rgba(66, 175, 250, 0.1),
    rgba(66, 175, 250, 0.05),
    transparent 40%
  );
  animation: rotate 6s linear infinite;
  z-index: 1;
}

@keyframes rotate {
  100% {
    transform: rotate(360deg);
  }
}

.cta-content {
  position: relative;
  z-index: 2;
  background: rgba(18, 18, 18, 0.95);
  border-radius: 20px;
  padding: 3rem;
  max-width: 700px;
  margin: 0 auto;
  backdrop-filter: blur(10px);
  border: 1px solid var(--card-border);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.5);
  transition: var(--transition-bounce);
}

/* 浅色主题下的CTA内容区域样式 */
body.light-theme .cta-content {
  background: rgba(255, 255, 255, 0.95);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.15);
}

.cta-content:hover {
  transform: scale(1.02);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.6);
}

/* 浅色主题下的CTA内容区域悬停效果 */
body.light-theme .cta-content:hover {
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
}

.cta-content::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  border-radius: 20px;
  box-shadow: inset 0 0 20px rgba(66, 175, 250, 0.1);
  pointer-events: none;
  z-index: -1;
}

/* 浅色主题下的CTA内容区域内阴影 */
body.light-theme .cta-content::before {
  box-shadow: inset 0 0 20px rgba(66, 175, 250, 0.2);
}

.cta-section h2 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  color: var(--brand-primary);
}

.cta-section p {
  font-size: 1.2rem;
  color: var(--brand-text-secondary);
  margin-bottom: 2rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

/* 按钮样式 */
.btn {
  padding: 0.5rem 1.5rem;
  border-radius: var(--border-radius-button);
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition-default);
  text-decoration: none;
  display: inline-block;
  text-align: center;
  position: relative;
  overflow: hidden;
  z-index: 1;
  border: none;
  font-size: 1rem;
  letter-spacing: 0.5px;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--gradient-button);
  transition: var(--transition-default);
  z-index: -1;
}

.btn:hover::before {
  background: var(--gradient-button-hover);
  transform: scale(1.05);
}

.btn:active {
  transform: scale(0.98);
}

.btn.large {
  padding: 1rem 2.5rem;
  font-size: 1.1rem;
}

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

.btn-outline::before {
  background: transparent;
}

.btn-outline:hover {
  background: var(--brand-primary);
  color: var(--brand-dark);
  box-shadow: 0 4px 15px rgba(66, 175, 250, 0.4);
}

.btn-primary {
  background: var(--gradient-button);
  border: 2px solid var(--brand-primary);
  color: var(--brand-dark);
  box-shadow: 0 4px 15px rgba(66, 175, 250, 0.4);
}

.btn-primary:hover {
  background: var(--gradient-button-hover);
  border-color: var(--brand-primary-darker);
  transform: translateY(-3px);
  box-shadow: 0 6px 20px rgba(66, 175, 250, 0.6);
}

/* 主题切换按钮样式 */
#theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: 2px solid var(--brand-primary);
  color: var(--brand-primary);
  cursor: pointer;
  transition: var(--transition-default);
  font-size: 1.2rem;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  padding: 0;
  position: relative;
  z-index: 1001; /* 确保按钮在顶层 */
}

#theme-toggle:hover {
  background: var(--brand-primary);
  color: var(--brand-dark);
  transform: scale(1.1);
}

/* 模态框样式 */
.modal {
  display: none;
  position: fixed;
  z-index: 2000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(5px);
  animation: fadeIn 0.3s ease;
}

.modal-content {
  background: var(--card-bg);
  margin: 5% auto;
  padding: 2rem;
  border: 1px solid var(--card-border);
  border-radius: var(--border-radius-default);
  width: 90%;
  max-width: 500px;
  position: relative;
  box-shadow: var(--shadow-hover);
  backdrop-filter: blur(10px);
  animation: slideIn 0.3s ease;
  transition: var(--transition-bounce);
}

@keyframes slideIn {
  from {
    transform: translateY(-50px);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

.modal-content h1 {
  font-size: 1.4rem;
  text-align: center;
  margin-bottom: 1.5rem;
  color: var(--brand-primary);
}

.modal-content h2 {
  text-align: center;
  margin-bottom: 1.5rem;
  color: var(--brand-primary);
}

.close {
  color: var(--brand-text-muted);
  float: right;
  font-size: 2rem;
  font-weight: bold;
  position: absolute;
  top: 1rem;
  right: 1.5rem;
  cursor: pointer;
  transition: color 0.3s ease;
}

.close:hover,
.close:focus {
  color: var(--brand-primary);
}

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

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  color: var(--brand-text);
  font-weight: 500;
}

.form-group input {
  width: 100%;
  padding: 0.8rem;
  border-radius: 8px;
  border: 1px solid var(--card-border);
  background: rgba(15, 15, 15, 0.7);
  color: var(--brand-text);
  font-size: 1rem;
  transition: var(--transition-default);
}

.form-group input:focus {
  outline: none;
  border-color: var(--brand-primary);
  box-shadow: 0 0 0 2px rgba(66, 175, 250, 0.3);
}

.full-width {
  width: 100%;
}

.form-footer {
  text-align: center;
  margin-top: 1rem;
}

.form-footer a {
  color: var(--brand-primary);
  text-decoration: none;
  font-size: 0.9rem;
  transition: var(--transition-default);
}

.form-footer a:hover {
  color: var(--brand-primary-light);
  text-decoration: underline;
}

/* 动画效果 */
@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

/* 响应式设计 */
@media (max-width: 992px) {
  .hero-title {
    font-size: 2.8rem;
  }
  
  .subtitle {
    font-size: 1.3rem;
  }
}

@media (max-width: 768px) {
  .navbar {
    padding: 1rem;
  }
  
  .nav-links {
    display: none;
  }
  
  .hero-title {
    font-size: 2.3rem;
  }
  
  .subtitle {
    font-size: 1.1rem;
  }
  
  .hero-buttons {
    flex-direction: column;
    align-items: center;
  }
  
  .features-section, .how-it-works-section, .testimonials-section, .cta-section, .advantages-section {
    padding: 4rem 1.5rem;
  }
  
  .section-title h2 {
    font-size: 2rem;
  }
  
  .features, .steps, .testimonials, .advantages-grid {
    grid-template-columns: 1fr;
  }
  
  .testimonials {
    grid-template-columns: 1fr;
  }
  
  .cta-section h2 {
    font-size: 2rem;
  }
  
  .modal-content {
    width: 95%;
    margin: 10% auto;
    padding: 1.5rem;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 2rem;
  }
  
  .subtitle {
    font-size: 1rem;
  }
  
  .btn {
    padding: 0.8rem 1.5rem;
    font-size: 0.9rem;
  }
  
  .section-title h2 {
    font-size: 1.8rem;
  }
}

/* 个性化推荐区域 */
.recommendations-section {
  padding: 6rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
  text-align: center;
  background: var(--section-bg);
  position: relative;
  overflow: hidden;
}

.recommendations-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at center, rgba(107, 255, 153, 0.1) 0%, transparent 70%);
}

.recommendations-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
  position: relative;
  z-index: 2;
}

.recommendation-card {
  background: var(--card-bg);
  border-radius: var(--border-radius-default);
  padding: 2rem;
  border: 1px solid var(--card-border);
  transition: var(--transition-bounce);
  text-align: center;
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-default);
  position: relative;
  overflow: hidden;
}

.recommendation-card:hover {
  transform: translateY(-10px) scale(1.02);
  border-color: var(--card-border-hover);
  box-shadow: var(--shadow-hover);
}

.recommendation-icon {
  font-size: 2.5rem;
  color: var(--brand-primary);
  margin-bottom: 1.5rem;
  background: rgba(66, 175, 250, 0.1);
  width: 80px;
  height: 80px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  margin: 0 auto 1.5rem;
  transition: var(--transition-default);
}

.recommendation-card:hover .recommendation-icon {
  transform: scale(1.1);
  background: rgba(66, 175, 250, 0.2);
  box-shadow: 0 0 20px rgba(66, 175, 250, 0.3);
}

.recommendation-card h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--brand-primary);
}

.recommendation-card p {
  color: var(--brand-text-secondary);
  line-height: 1.6;
  margin-bottom: 1.5rem;
}

.recommendation-card .btn {
  margin-top: 1rem;
}