/* 基础样式 - Base Styles */
:root {
  --primary: #D80621;
  --secondary: #FF5F40;
  --accent: #FFCB05;
  --dark: #0A0A0A;
  --light: #F8F8F8;
  --gray: #5A5A5A;
  --gradient: linear-gradient(120deg, var(--primary), var(--secondary));
  --box-shadow: 0 5px 15px rgba(216, 6, 33, 0.1);
  --transition: all 0.3s ease;
  --border-radius: 10px;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Noto Sans SC', 'Microsoft YaHei', sans-serif;
  color: var(--dark);
  background-color: var(--light);
  line-height: 1.6;
  overflow-x: hidden;
}

.container {
  width: 90%;
  max-width: 1200px;
  margin: 0 auto;
}

/* 排版 - Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1rem;
}

h1 {
  font-size: 3rem;
}

h2 {
  font-size: 2.5rem;
}

h3 {
  font-size: 1.75rem;
}

p {
  margin-bottom: 1.5rem;
}

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

.section-title {
  position: relative;
  margin-bottom: 3rem;
  text-align: center;
  padding-bottom: 1rem;
}

.section-title::after {
  content: '';
  position: absolute;
  height: 4px;
  width: 60px;
  background: var(--gradient);
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  border-radius: 2px;
}

/* 按钮 - Buttons */
.btn {
  display: inline-block;
  background: var(--gradient);
  color: var(--light);
  padding: 12px 30px;
  border-radius: 30px;
  text-decoration: none;
  font-weight: 600;
  box-shadow: var(--box-shadow);
  transition: var(--transition);
  border: none;
  cursor: pointer;
  text-align: center;
  text-transform: uppercase;
  font-size: 0.9rem;
}

.btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 20px rgba(216, 6, 33, 0.2);
}

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

.btn-outline:hover {
  background: var(--gradient);
  color: var(--light);
}

.btn-large {
  padding: 14px 40px;
  font-size: 1rem;
}

/* 导航栏 - Header & Navigation */
.header {
  position: fixed;
  width: 100%;
  top: 0;
  left: 0;
  padding: 20px 0;
  z-index: 100;
  background-color: rgba(248, 248, 248, 0.95);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  transition: var(--transition);
}

.header.scrolled {
  padding: 10px 0;
}

.header-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-img {
  height: 40px;
  width: auto;
}

.logo-text {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 1.5rem;
  align-items: center;
}

.nav-item a {
  text-decoration: none;
  color: var(--dark);
  font-weight: 500;
  transition: var(--transition);
  padding: 8px 12px;
  border-radius: var(--border-radius);
}

.nav-item a:hover {
  color: var(--primary);
  background-color: rgba(216, 6, 33, 0.05);
}

.mobile-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--dark);
  font-size: 1.5rem;
  cursor: pointer;
}

/* 英雄部分 - Hero Section */
.hero {
  height: 100vh;
  min-height: 600px;
  background: var(--gradient);
  position: relative;
  display: flex;
  align-items: center;
  overflow: hidden;
  color: var(--light);
}

.hero-content {
  position: relative;
  z-index: 2;
}

.hero-title {
  margin-bottom: 1.5rem;
}

.hero-description {
  max-width: 600px;
  margin-bottom: 2rem;
  font-size: 1.1rem;
}

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

.hero-pattern {
  position: absolute;
  height: 100%;
  width: 100%;
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.05'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
  opacity: 0.3;
}

/* 功能部分 - Features Section */
.features {
  padding: 100px 0;
  background-color: var(--light);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

.feature-card {
  background-color: #fff;
  border-radius: var(--border-radius);
  padding: 2rem;
  transition: var(--transition);
  box-shadow: var(--box-shadow);
  text-align: center;
  border-bottom: 4px solid transparent;
}

.feature-card:hover {
  transform: translateY(-10px);
  border-bottom: 4px solid var(--primary);
}

.feature-icon {
  width: 60px;
  height: 60px;
  margin: 0 auto 1.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--gradient);
  color: var(--light);
}

.feature-icon svg {
  width: 30px;
  height: 30px;
}

.feature-title {
  margin-bottom: 1rem;
}

/* 如何工作部分 - How It Works Section */
.how-it-works {
  padding: 100px 0;
  background-color: var(--light);
}

.steps {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
}

.step {
  flex: 0 0 calc(33.333% - 2rem);
  text-align: center;
  padding: 2rem;
  position: relative;
  background-color: #fff;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
}

.step-number {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--gradient);
  color: var(--light);
  font-weight: 700;
  margin: 0 auto 1rem;
}

.step-title {
  margin-bottom: 1rem;
}

.step::after {
  content: '';
  position: absolute;
  top: 50%;
  right: -10%;
  height: 2px;
  width: 20%;
  background: var(--gray);
  opacity: 0.3;
}

.step:last-child::after {
  display: none;
}

/* 评价部分 - Testimonials */
.testimonials {
  padding: 100px 0;
  background-color: #fff;
}

.testimonial-card {
  background-color: var(--light);
  border-radius: var(--border-radius);
  padding: 2rem;
  box-shadow: var(--box-shadow);
  margin-bottom: 2rem;
  position: relative;
}

.testimonial-text {
  font-style: italic;
  margin-bottom: 1.5rem;
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.author-info h4 {
  margin-bottom: 0.25rem;
}

.author-info p {
  color: var(--gray);
  margin: 0;
}

/* 行动号召部分 - CTA Section */
.cta {
  padding: 80px 0;
  background: var(--gradient);
  color: var(--light);
  text-align: center;
}

.cta-title {
  margin-bottom: 1.5rem;
  color: var(--light);
}

.cta-text {
  max-width: 700px;
  margin: 0 auto 2rem;
}

/* 页脚 - Footer */
.footer {
  padding: 80px 0 30px;
  background-color: var(--dark);
  color: var(--light);
}

.footer-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 3rem;
}

.footer-col h3 {
  color: var(--light);
  margin-bottom: 1.5rem;
  position: relative;
  padding-bottom: 0.5rem;
}

.footer-col h3::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 40px;
  height: 3px;
  background: var(--primary);
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 0.75rem;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.7);
  text-decoration: none;
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--light);
  padding-left: 5px;
}

.footer-logo img {
  max-width: 100px;
  margin-bottom: 1rem;
}

.copyright {
  text-align: center;
  margin-top: 4rem;
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  color: rgba(255, 255, 255, 0.7);
}

/* 动画效果 - Animations */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* 响应式设计 - Responsive Design */
@media (max-width: 992px) {
  h1 {
    font-size: 2.5rem;
  }
  
  h2 {
    font-size: 2rem;
  }
  
  .step {
    flex: 0 0 100%;
    margin-bottom: 2rem;
  }
  
  .step::after {
    display: none;
  }
}

@media (max-width: 768px) {
  .mobile-toggle {
    display: block;
  }
  
  .nav-menu {
    position: fixed;
    top: 70px;
    right: -100%;
    width: 70%;
    height: 100vh;
    background-color: var(--light);
    flex-direction: column;
    align-items: center;
    padding: 2rem;
    transition: var(--transition);
    box-shadow: -5px 0 15px rgba(0, 0, 0, 0.1);
  }
  
  .nav-menu.active {
    right: 0;
  }
  
  .hero-buttons {
    flex-direction: column;
  }
  
  .features-grid {
    grid-template-columns: 1fr;
  }
  
  .footer-container {
    grid-template-columns: 1fr;
    text-align: center;
  }
  
  .footer-col h3::after {
    left: 50%;
    transform: translateX(-50%);
  }
}

@media (max-width: 576px) {
  h1 {
    font-size: 2rem;
  }
  
  h2 {
    font-size: 1.75rem;
  }
  
  .section-title {
    font-size: 1.75rem;
  }
}