@charset "utf-8";

:root {
  --primary-color: #3498db;
  --secondary-color: #2c3e50;
  --accent-color: #e74c3c;
  --light-color: #ecf0f1;
  --dark-color: #2c3e50;
  --text-color: #333;
  --text-light: #7f8c8d;
  --link-ad-color: #9b59b6;
  --success-color: #2ecc71;
  --card-ad-color: #ff9f43;
  --safe-area-inset-top: env(safe-area-inset-top);
  --safe-area-inset-bottom: env(safe-area-inset-bottom);
  --safe-area-inset-left: env(safe-area-inset-left);
  --safe-area-inset-right: env(safe-area-inset-right);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

html {
  font-size: 100%;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  color: var(--text-color);
  background-color: #f9f9f9;
  min-height: 100vh;
  padding: var(--safe-area-inset-top) var(--safe-area-inset-right) var(--safe-area-inset-bottom) var(--safe-area-inset-left);
}

.container {
  max-width: 1660px;
  margin: 0 auto;
  padding: 0 1rem;
}

/* Header & Navigation */
header {
  background-color: var(--secondary-color);
  color: white;
  padding: 0;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  top: 0;
  z-index: 100;
  position: sticky;
}

.header-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.75rem 1rem;
}

.logo {
  font-size: clamp(1.25rem, 4vw, 1.75rem);
  font-weight: bold;
  color: white;
  text-decoration: none;
}

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

nav ul {
  display: flex;
  list-style: none;
  gap: 1rem;
}

nav ul li a {
  color: white;
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s;
  font-size: clamp(0.875rem, 2.5vw, 1rem);
}

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

.mobile-menu {
  display: none;
  font-size: 1.5rem;
  cursor: pointer;
  background: none;
  border: none;
  color: white;
}

/* Hero Section */
.hero {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  padding: clamp(3rem, 8vw, 5rem) 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100" preserveAspectRatio="none"><path d="M0,0 L100,0 L100,100 Z" fill="rgba(255,255,255,0.05)"/></svg>');
  background-size: cover;
}

.hero h1 {
  font-size: clamp(1.75rem, 5vw, 2.625rem);
  margin-bottom: 1.25rem;
  position: relative;
  line-height: 1.2;
}

.hero p {
  font-size: clamp(1rem, 3vw, 1.25rem);
  max-width: min(800px, 90%);
  margin: 0 auto clamp(1.875rem, 5vw, 2.5rem);
  position: relative;
  line-height: 1.5;
}

.hero-btn {
  display: inline-block;
  background-color: var(--accent-color);
  color: white;
  padding: clamp(0.75rem, 2vw, 0.9375rem) clamp(1.25rem, 4vw, 2.1875rem);
  border-radius: 50px;
  text-decoration: none;
  font-weight: bold;
  transition: all 0.3s;
  margin: 0.5rem;
  position: relative;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
  font-size: clamp(0.875rem, 2.5vw, 1rem);
  border: none;
  cursor: pointer;
}

.hero-btn:hover {
  background-color: #c0392b;
  transform: translateY(-3px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.25);
}

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

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

/* General Section Styles */
.section {
  padding: clamp(2.5rem, 6vw, 5rem) 0;
}

.section-title {
  text-align: center;
  margin-bottom: clamp(2rem, 5vw, 3.125rem);
}

.section-title h2 {
  font-size: clamp(1.5rem, 4vw, 2.25rem);
  color: var(--secondary-color);
  position: relative;
  display: inline-block;
  padding-bottom: 0.9375rem;
  margin-bottom: 0.9375rem;
  line-height: 1.2;
}

.section-title h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 5rem;
  height: 0.25rem;
  background-color: var(--primary-color);
  border-radius: 0.125rem;
}

.section-title p {
  font-size: clamp(1rem, 2.5vw, 1.125rem);
  color: #00BFFF;
  max-width: min(700px, 90%);
  margin: 0 auto;
  line-height: 1.5;
}

.link-ad-title h2::after,
.link-ad-card h3 {
  border-bottom-color: var(--link-ad-color);
}

.card-ad-title h2::after,
.card-ad h3 {
  border-bottom-color: var(--card-ad-color);
}

/* Buttons */
.btn {
  display: inline-block;
  background-color: var(--accent-color);
  color: white;
  padding: 0.875rem 1.75rem;
  border-radius: 0.5rem;
  text-decoration: none;
  font-weight: bold;
  transition: all 0.3s;
  margin-top: 0.9375rem;
  text-align: center;
  border: none;
  cursor: pointer;
  font-size: 1rem;
}

.btn:hover {
  background-color: #c0392b;
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.link-ad-btn {
  background-color: var(--link-ad-color);
}

.link-ad-btn:hover {
  background-color: #8e44ad;
}

.card-ad-btn {
  background-color: var(--card-ad-color);
}

.card-ad-btn:hover {
  background-color: #f39c12;
}

/* Card Styles */
.ad-options {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(320px, 100%), 1fr));
  gap: clamp(1rem, 3vw, 1.875rem);
  margin-bottom: clamp(2rem, 5vw, 3.125rem);
}

.ad-card, .cdn-card, .feature-card, .card-ad {
  background-color: white;
  border-radius: 0.75rem;
  overflow: hidden;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
  padding: clamp(1.25rem, 3vw, 1.875rem);
  transition: all 0.3s ease;
  position: relative;
  border: 1px solid #f1f1f1;
}

.ad-card:hover, .cdn-card:hover, .feature-card:hover, .card-ad:hover {
  transform: translateY(-0.625rem);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.12);
}

.ad-card h3, .cdn-card h3, .feature-card h3, .card-ad h3 {
  font-size: clamp(1.25rem, 3vw, 1.5rem);
  margin-bottom: 0.9375rem;
  color: var(--secondary-color);
  padding-bottom: 0.9375rem;
  border-bottom: 2px solid var(--primary-color);
  line-height: 1.3;
}

.ad-card .popular {
  position: absolute;
  top: 1.25rem;
  right: 1.25rem;
  background: var(--accent-color);
  color: white;
  padding: 0.3125rem 0.9375rem;
  border-radius: 1.25rem;
  font-size: 0.75rem;
  font-weight: bold;
}

.ad-card .price, .card-ad .price {
  font-size: clamp(1.5rem, 4vw, 2rem);
  font-weight: bold;
  color: var(--accent-color);
  margin: 1.25rem 0;
  line-height: 1.2;
}

.ad-card .price span, .card-ad .price span {
  font-size: 1rem;
  color: var(--text-light);
  font-weight: normal;
}

.ad-card ul {
  margin: 1.25rem 0;
  padding-left: 1.25rem;
}

.ad-card ul li {
  margin-bottom: 0.75rem;
  position: relative;
  padding-left: 1.5625rem;
  line-height: 1.5;
}

.ad-card ul li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--success-color);
  font-weight: bold;
}

/* CDN Providers */
.cdn-providers {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(350px, 100%), 1fr));
  gap: clamp(1rem, 3vw, 1.875rem);
}

.cdn-features {
  margin: 0.9375rem 0;
}

.cdn-features li {
  margin-bottom: 0.5rem;
  display: flex;
  align-items: center;
  line-height: 1.5;
}

.cdn-features li i {
  color: var(--primary-color);
  margin-right: 0.5rem;
  font-size: 0.875rem;
}

.cdn-card a {
  color: var(--primary-color);
  text-decoration: none;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  margin-top: 0.9375rem;
}

.cdn-card a i {
  margin-left: 0.3125rem;
  transition: transform 0.3s;
}

.cdn-card a:hover i {
  transform: translateX(0.3125rem);
}

.cdn-card a::after {
  content: '➞';
  position: absolute;
  left: 8.5rem;
  color: var(--success-color);
  font-weight: bold;
}

/* Features Grid */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(300px, 100%), 1fr));
  gap: clamp(1rem, 3vw, 1.875rem);
}

.feature-card i {
  font-size: clamp(2rem, 5vw, 2.5rem);
  color: var(--primary-color);
  margin-bottom: 1.25rem;
}

/* FAQ & Accordion Styles */
.faq-item, .accordion-item {
  margin-bottom: 1.5625rem;
  border: 1px solid #eee;
  border-radius: 0.75rem;
  overflow: hidden;
  background: white;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
}

.faq-question, .accordion-header {
  background-color: var(--light-color);
  padding: clamp(1rem, 3vw, 1.5625rem);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: 600;
  font-size: clamp(1rem, 2.5vw, 1.125rem);
  line-height: 1.4;
}

.faq-question:hover, .accordion-header:hover {
  background-color: #e0e0e0;
}

.faq-answer, .accordion-content {
  padding: 0 clamp(1rem, 3vw, 1.5625rem);
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease-out, padding 0.4s ease;
}

.faq-item.active .faq-answer,
.accordion-item.active .accordion-content {
  padding: clamp(1rem, 3vw, 1.5625rem);
  max-height: 500px;
}

/* Comparison Table - 修复表格溢出问题 */
.table-container {
  width: 100%;
  overflow-x: auto;
  margin: 1.875rem 0;
  -webkit-overflow-scrolling: touch;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  border-radius: 0.5rem;
}

.comparison-table {
  width: 100%;
  min-width: 600px; /* 确保表格有最小宽度 */
  border-collapse: collapse;
}

.comparison-table th, .comparison-table td {
  padding: clamp(0.75rem, 2vw, 0.9375rem);
  text-align: left;
  border-bottom: 1px solid #ddd;
  line-height: 1.5;
  word-break: break-word;
}

.comparison-table th {
  background-color: var(--secondary-color);
  color: white;
  position: sticky;
  left: 0;
  font-size: clamp(0.875rem, 2vw, 1rem);
}

.comparison-table tr:nth-child(even) {
  background-color: #f2f2f2;
}

.comparison-table tr:hover {
  background-color: #e9e9e9;
}

/* 移动端表格优化 */
@media (max-width: 768px) {
  .comparison-table {
    font-size: 0.875rem;
  }
  
  .comparison-table th, 
  .comparison-table td {
    padding: 0.5rem;
  }
  
  /* 为小屏幕设备进一步优化 */
  @media (max-width: 480px) {
    .comparison-table {
      min-width: 500px; /* 更小的最小宽度 */
    }
    
    .comparison-table th, 
    .comparison-table td {
      padding: 0.375rem;
      font-size: 0.75rem;
    }
  }
}

/* Badges */
.badge {
  display: inline-block;
  padding: 0.1875rem 0.5rem;
  border-radius: 0.25rem;
  font-size: 0.75rem;
  font-weight: bold;
}

.badge-green {
  background-color: #2ecc71;
  color: white;
}

.badge-blue {
  background-color: #3498db;
  color: white;
}

.badge-orange {
  background-color: #e67e22;
  color: white;
}

/* Payment Methods */
.payment-methods {
  background-color: var(--light-color);
  padding: clamp(1.5rem, 4vw, 3.125rem);
  border-radius: 0.75rem;
  margin-bottom: clamp(2rem, 5vw, 3.125rem);
}

.payment-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(200px, 100%), 1fr));
  gap: clamp(1rem, 3vw, 1.5625rem);
  margin-top: 1.875rem;
}

.payment-method {
  text-align: center;
  padding: clamp(1rem, 3vw, 1.5625rem);
  background-color: white;
  border-radius: 0.75rem;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
  transition: transform 0.3s;
}

.payment-method:hover {
  transform: translateY(-0.3125rem);
}

.payment-method i {
  font-size: clamp(2rem, 5vw, 3rem);
  color: var(--primary-color);
  margin-bottom: 1.25rem;
}

/* Payment Details */
.payment-details {
  background-color: white;
  padding: clamp(1.5rem, 4vw, 3.125rem);
  border-radius: 0.75rem;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
  margin: clamp(1.5rem, 4vw, 2.5rem) 0;
}

.payment-details h3 {
  color: var(--secondary-color);
  margin-bottom: clamp(1.5rem, 4vw, 2.5rem);
  text-align: center;
  font-size: clamp(1.5rem, 4vw, 2rem);
}

.payment-info-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(300px, 100%), 1fr));
  gap: clamp(1rem, 3vw, 2.1875rem);
}

.payment-info-card {
  padding: clamp(1rem, 3vw, 1.5625rem);
  border: 1px solid #eee;
  border-radius: 0.75rem;
  text-align: center;
  transition: transform 0.3s;
}

.payment-info-card:hover {
  transform: translateY(-0.3125rem);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.08);
}

.payment-info-card h4 {
  color: var(--secondary-color);
  margin-bottom: 1.25rem;
  font-size: clamp(1.125rem, 3vw, 1.375rem);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
}

.payment-info-card h4 i {
  margin-right: 0.75rem;
  color: var(--primary-color);
}

.qr-code {
  width: clamp(150px, 40vw, 200px);
  height: clamp(150px, 40vw, 200px);
  margin: 1.25rem auto;
  background-color: #f9f9f9;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid #eee;
  border-radius: 0.75rem;
  overflow: hidden;
  padding: 0.9375rem;
}

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

.account-info {
  background-color: #f9f9f9;
  padding: 1.25rem;
  border-radius: 0.5rem;
  margin-top: 1.25rem;
  text-align: left;
}

.account-info p {
  margin: 0.625rem 0;
  font-size: 0.9375rem;
  word-break: break-all;
  line-height: 1.5;
}

.account-info strong {
  color: var(--secondary-color);
}

.copy-btn {
  background-color: var(--primary-color);
  color: white;
  border: none;
  padding: 0.5rem 1rem;
  border-radius: 0.375rem;
  cursor: pointer;
  margin-top: 0.75rem;
  font-size: 0.875rem;
  transition: background-color 0.3s;
}

.copy-btn:hover {
  background-color: #2980b9;
}

.instructions {
  margin-top: 1.25rem;
  font-size: 0.9375rem;
  color: var(--text-light);
  line-height: 1.6;
}

/* Process Steps */
.process-steps {
  margin: clamp(2rem, 5vw, 3.75rem) 0;
}

.process-step {
  display: flex;
  margin-bottom: clamp(2rem, 5vw, 3.125rem);
  position: relative;
}

.process-step:not(:last-child)::after {
  content: '';
  position: absolute;
  left: 1.875rem;
  top: 5rem;
  bottom: -3.125rem;
  width: 0.1875rem;
  background-color: var(--primary-color);
  opacity: 0.3;
  border-radius: 0.125rem;
}

.step-number {
  width: clamp(3.5rem, 8vw, 4.375rem);
  height: clamp(3.5rem, 8vw, 4.375rem);
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-color), #2a5c85);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: clamp(1.25rem, 3vw, 1.75rem);
  font-weight: bold;
  margin-right: clamp(1rem, 3vw, 1.875rem);
  flex-shrink: 0;
  z-index: 1;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.step-content {
  background-color: white;
  padding: clamp(1.25rem, 3vw, 1.875rem);
  border-radius: 0.75rem;
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.08);
  flex-grow: 1;
}

.step-content h3 {
  color: var(--secondary-color);
  margin-bottom: 1.25rem;
  font-size: clamp(1.25rem, 3vw, 1.5rem);
}

.step-content ul {
  margin: 1.25rem 0;
  padding-left: 1.5625rem;
}

.step-content ul li {
  margin-bottom: 0.625rem;
  line-height: 1.5;
}

.note {
  font-style: italic;
  color: var(--text-light);
  margin-top: 1.25rem;
  font-size: 0.9375rem;
  padding: 0.9375rem;
  background-color: #f9f9f9;
  border-left: 0.25rem solid var(--primary-color);
  border-radius: 0.25rem;
  line-height: 1.5;
}

/* Ad Guidelines */
.ad-guidelines {
  margin-top: clamp(2.5rem, 6vw, 5rem);
}

.ad-guidelines h3 {
  text-align: center;
  color: var(--secondary-color);
  margin-bottom: clamp(2rem, 5vw, 3.125rem);
  font-size: clamp(1.5rem, 4vw, 2rem);
}

.guidelines-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(300px, 100%), 1fr));
  gap: clamp(1rem, 3vw, 2.1875rem);
}

.guideline-card {
  background-color: white;
  padding: clamp(1.5rem, 4vw, 2.1875rem);
  border-radius: 0.75rem;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
  transition: transform 0.3s;
}

.guideline-card:hover {
  transform: translateY(-0.5rem);
}

.guideline-card h4 {
  color: var(--secondary-color);
  margin-bottom: 1.25rem;
  font-size: clamp(1.125rem, 3vw, 1.375rem);
  display: flex;
  align-items: center;
  flex-wrap: wrap;
}

.guideline-card h4 i {
  margin-right: 0.9375rem;
  color: var(--primary-color);
  font-size: clamp(1.25rem, 3vw, 1.625rem);
}

/* Link Ad Features */
.link-ad-features {
  background: linear-gradient(135deg, #6a11cb 0%, #2575fc 100%);
  color: white;
  padding: clamp(2.5rem, 6vw, 5rem) 0;
  margin: clamp(2rem, 5vw, 3.75rem) 0;
  border-radius: 0.9375rem;
  position: relative;
  overflow: hidden;
}

.link-ad-features::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100" preserveAspectRatio="none"><path d="M0,0 L100,0 L100,100 Z" fill="rgba(255,255,255,0.05)"/></svg>');
  background-size: cover;
}

.link-ad-features .container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(300px, 100%), 1fr));
  gap: clamp(1.5rem, 4vw, 2.5rem);
  position: relative;
}

.link-ad-feature-card {
  text-align: center;
  padding: clamp(1.5rem, 4vw, 2.5rem) clamp(1rem, 3vw, 1.875rem);
  background: rgba(255, 255, 255, 0.1);
  border-radius: 0.9375rem;
  backdrop-filter: blur(0.3125rem);
  transition: transform 0.3s;
}

.link-ad-feature-card:hover {
  transform: translateY(-0.5rem);
  background: rgba(255, 255, 255, 0.15);
}

.feature-icon {
  font-size: clamp(2.5rem, 6vw, 3.75rem);
  margin-bottom: clamp(1rem, 3vw, 1.5625rem);
  color: white;
}

.link-ad-feature-card h3 {
  margin-bottom: 1.25rem;
  font-size: clamp(1.25rem, 3vw, 1.5rem);
}

/* Link Ad Examples */
.link-ad-examples {
  margin: clamp(2.5rem, 6vw, 4.375rem) 0;
}

.example-container {
  background-color: white;
  border-radius: 0.9375rem;
  padding: clamp(1.5rem, 4vw, 2.5rem);
  box-shadow: 0 15px 40px rgba(0, 0, 0, 0.1);
  margin-top: clamp(1.5rem, 4vw, 2.5rem);
}

.example-item {
  margin-bottom: clamp(1.5rem, 4vw, 2.5rem);
  padding: clamp(1rem, 3vw, 1.875rem);
  border: 1px solid #eee;
  border-radius: 0.75rem;
  transition: transform 0.3s;
}

.example-item:hover {
  transform: translateY(-0.3125rem);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.08);
}

.example-item:last-child {
  margin-bottom: 0;
}

.example-item h4 {
  color: var(--secondary-color);
  margin-bottom: 1.25rem;
  padding-bottom: 0.9375rem;
  border-bottom: 2px solid #eee;
  font-size: clamp(1.125rem, 3vw, 1.375rem);
}

.example-preview {
  background-color: #f8f9fa;
  padding: clamp(1rem, 3vw, 1.5625rem);
  border-radius: 0.625rem;
  margin-top: 1.25rem;
  border-left: 0.3125rem solid var(--link-ad-color);
}

.example-preview a {
  color: var(--link-ad-color);
  text-decoration: none;
  font-weight: 600;
}

.example-preview a:hover {
  text-decoration: underline;
}

.example-preview p {
  margin: 0.9375rem 0;
  color: var(--text-light);
  font-size: 1rem;
  line-height: 1.6;
}

/* Process Visual */
.process-visual {
  margin-top: clamp(2.5rem, 6vw, 5rem);
  text-align: center;
}

.process-visual h3 {
  color: var(--secondary-color);
  margin-bottom: clamp(2rem, 5vw, 3.125rem);
  font-size: clamp(1.5rem, 4vw, 2rem);
}

.process-flow {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
}

.flow-step {
  text-align: center;
  padding: clamp(1rem, 3vw, 1.5625rem);
  background-color: white;
  border-radius: 0.9375rem;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  width: clamp(120px, 25vw, 140px);
  margin: 0 clamp(0.5rem, 2vw, 0.9375rem);
  transition: transform 0.3s;
}

.flow-step:hover {
  transform: translateY(-0.5rem);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.15);
}

.flow-icon {
  width: clamp(3rem, 7vw, 3.75rem);
  height: clamp(3rem, 7vw, 3.75rem);
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-color), #2a5c85);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.25rem;
  font-size: clamp(1.125rem, 3vw, 1.5rem);
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.flow-arrow {
  color: var(--primary-color);
  font-size: clamp(1.125rem, 3vw, 1.5rem);
  margin: 0 clamp(0.5rem, 2vw, 0.625rem);
}

/* Contact Form */
.contact-form-container {
  background-color: white;
  padding: clamp(1.5rem, 4vw, 3.125rem);
  border-radius: 0.9375rem;
  box-shadow: 0 15px 40px rgba(0, 0, 0, 0.1);
  margin: clamp(2rem, 5vw, 3.75rem) 0;
}

.form-title {
  text-align: center;
  margin-bottom: clamp(1.5rem, 4vw, 2.5rem);
}

.form-title h3 {
  color: var(--secondary-color);
  font-size: clamp(1.5rem, 4vw, 2rem);
  margin-bottom: 0.9375rem;
}

.form-title p {
  color: var(--text-light);
  font-size: clamp(1rem, 2.5vw, 1.125rem);
}

.contact-form {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(300px, 100%), 1fr));
  gap: clamp(1rem, 3vw, 1.5625rem);
}

.form-group {
  margin-bottom: clamp(1rem, 3vw, 1.5625rem);
}

.form-group.full-width {
  grid-column: 1 / -1;
}

.form-group label {
  display: block;
  margin-bottom: 0.625rem;
  font-weight: 600;
  color: var(--secondary-color);
  font-size: clamp(0.875rem, 2.5vw, 1rem);
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: clamp(0.75rem, 2vw, 0.9375rem) clamp(1rem, 3vw, 1.25rem);
  border: 1px solid #ddd;
  border-radius: 0.5rem;
  font-size: 1rem;
  transition: border-color 0.3s, box-shadow 0.3s;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2);
}

.form-group textarea {
  min-height: 9.375rem;
  resize: vertical;
}

.submit-btn {
  background-color: var(--accent-color);
  color: white;
  border: none;
  padding: clamp(0.875rem, 2vw, 1rem) clamp(1.5rem, 4vw, 2.1875rem);
  border-radius: 0.5rem;
  font-size: clamp(1rem, 2.5vw, 1.125rem);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s;
  grid-column: 1 / -1;
  justify-self: center;
  margin-top: 1.25rem;
  width: auto;
}

.submit-btn:hover {
  background-color: #c0392b;
  transform: translateY(-0.1875rem);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

.form-note {
  text-align: center;
  margin-top: clamp(1rem, 3vw, 1.5625rem);
  color: var(--text-light);
  font-size: 0.9375rem;
  grid-column: 1 / -1;
}

/* Ad Banner */
.ad-banner {
  margin: 1.25rem 0;
  padding: 0;
  background: #f8f9fa;
  text-align: center;
  border: 0 dashed #ddd;
  width: 100%;
  max-width: 1660px;
  height: auto;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.ad-label {
  font-size: 0.75rem;
  color: var(--text-light);
  text-transform: uppercase;
  letter-spacing: 0.0625rem;
  margin-bottom: 0.625rem;
}

.ad-banner p {
  color: var(--text-light);
  margin-bottom: 0.625rem;
}

/* Card Ads */
.card-ads {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(300px, 100%), 1fr));
  gap: clamp(1rem, 3vw, 1.875rem);
  margin: clamp(2rem, 5vw, 3.125rem) 0;
}

.card-ad .price {
  color: var(--card-ad-color);
}

.card-ad-example {
  background-color: #f8f9fa;
  padding: 1.25rem;
  border-radius: 0.5rem;
  margin: 1.25rem 0;
  border-left: 0.25rem solid var(--card-ad-color);
}

.card-ad-example h4 {
  color: var(--secondary-color);
  margin-bottom: 0.625rem;
}

.card-ad-example p {
  color: var(--text-light);
  margin-bottom: 0.9375rem;
  font-size: 0.875rem;
}

.card-ad-example .cta {
  display: inline-block;
  background-color: var(--card-ad-color);
  color: white;
  padding: 0.5rem 1rem;
  border-radius: 0.25rem;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.875rem;
}

.features {
  margin: 1.25rem 0;
  padding-left: 0;
  list-style: none;
}

.features li {
  margin-bottom: 0.75rem;
  position: relative;
  padding-left: 1.875rem;
  line-height: 1.5;
}

.features li i {
  position: absolute;
  left: 0;
  top: 0.125rem;
  color: var(--success-color);
}

/* General Card */
.card {
  background: white;
  border-radius: 0.75rem;
  padding: clamp(1rem, 3vw, 1.875rem);
  margin: clamp(1rem, 3vw, 1.875rem) 0;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
}

.card-title {
  font-size: clamp(1.25rem, 3vw, 1.5rem);
  color: var(--secondary-color);
  margin-bottom: 1.25rem;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
}

.card-title i {
  margin-right: 0.9375rem;
  color: var(--card-ad-color);
}

.card h4 {
  color: var(--secondary-color);
  margin: clamp(1rem, 3vw, 1.5625rem) 0 0.9375rem;
  font-size: clamp(1.125rem, 3vw, 1.25rem);
}

/* Contact Info */
.contact-info {
  background-color: var(--secondary-color);
  color: white;
  padding: clamp(1.5rem, 4vw, 3.125rem);
  border-radius: 0.75rem;
  text-align: center;
  margin: clamp(1.5rem, 4vw, 2.5rem) 0;
}

.contact-info a {
  color: var(--primary-color);
  text-decoration: none;
  font-weight: 600;
}

/* Footer */
footer {
  background-color: var(--dark-color);
  color: white;
  padding: clamp(2.5rem, 6vw, 3.75rem) 0 clamp(1.5rem, 4vw, 1.875rem);
  margin-top: clamp(1.5rem, 4vw, 2.5rem);
}

.footer-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(250px, 100%), 1fr));
  gap: clamp(1.5rem, 4vw, 2.5rem);
  margin-bottom: clamp(1.5rem, 4vw, 2.5rem);
  padding: 0.625rem clamp(1rem, 3vw, 1.875rem);
}

.footer-col h3 {
  font-size: clamp(1.125rem, 3vw, 1.375rem);
  margin-bottom: clamp(1rem, 3vw, 1.5625rem);
  position: relative;
  padding-bottom: 0.9375rem;
}

.footer-col h3::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 3.125rem;
  height: 0.1875rem;
  background-color: var(--primary-color);
  border-radius: 0.125rem;
}

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

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

.footer-col ul li a {
  color: #bdc3c7;
  text-decoration: none;
  transition: color 0.3s;
  font-size: clamp(0.875rem, 2.5vw, 1rem);
}

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

.social-links {
  display: flex;
  gap: 0.9375rem;
}

.social-links a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: clamp(2.5rem, 6vw, 2.5rem);
  height: clamp(2.5rem, 6vw, 2.5rem);
  background-color: rgba(255, 255, 255, 0.1);
  border-radius: 50%;
  color: white;
  transition: background-color 0.3s;
  font-size: clamp(1rem, 2.5vw, 1.125rem);
}

.social-links a:hover {
  background-color: var(--primary-color);
}

.copyright {
  text-align: center;
  padding: clamp(1rem, 3vw, 1.875rem) clamp(1rem, 3vw, 1.875rem);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  color: #bdc3c7;
  font-size: 0.9375rem;
}

.copyright a {
  text-decoration: none;
}

/* Animation */
.fade-in {
  opacity: 0;
  transform: translateY(1.25rem);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

.delay-1 {
  transition-delay: 0.2s;
}

.delay-2 {
  transition-delay: 0.4s;
}

.delay-3 {
  transition-delay: 0.6s;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(1.25rem); }
  to { opacity: 1; transform: translateY(0); }
}

.animated {
  animation: fadeIn 0.8s ease-out;
}

/* 触摸设备优化 */
@media (hover: none) {
  .ad-card:hover, 
  .cdn-card:hover, 
  .feature-card:hover, 
  .card-ad:hover,
  .guideline-card:hover,
  .payment-method:hover,
  .payment-info-card:hover,
  .flow-step:hover,
  .example-item:hover {
    transform: none;
  }
  
  .btn:hover,
  .hero-btn:hover,
  .submit-btn:hover {
    transform: none;
  }
}

/* 深色模式支持 */
@media (prefers-color-scheme: dark) {
  body {
    background-color: #1a1a1a;
    color: #f0f0f0;
  }
  
  .ad-card, 
  .cdn-card, 
  .feature-card, 
  .card-ad,
  .guideline-card,
  .step-content,
  .example-container,
  .example-item,
  .payment-info-card,
  .payment-method,
  .contact-form-container,
  .card {
    background-color: #2d2d2d;
    color: #f0f0f0;
    border-color: #444;
  }
  
  .ad-card h3, 
  .cdn-card h3, 
  .feature-card h3, 
  .card-ad h3,
  .step-content h3,
  .guideline-card h4,
  .payment-info-card h4,
  .card-title,
  .card h4 {
    color: #f0f0f0;
  }
  
  .comparison-table tr:nth-child(even) {
    background-color: #2d2d2d;
  }
  
  .comparison-table tr:hover {
    background-color: #3d3d3d;
  }
  
  .account-info,
  .note {
    background-color: #2d2d2d;
  }
  
  .example-preview {
    background-color: #2d2d2d;
    border-left-color: var(--link-ad-color);
  }
}

/* 减少动画（适用于偏好减少运动的用户） */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* 高对比度模式支持 */
@media (prefers-contrast: high) {
  :root {
    --primary-color: #0066cc;
    --secondary-color: #000000;
    --accent-color: #cc0000;
    --text-color: #000000;
    --text-light: #444444;
  }
  
  body {
    background-color: #ffffff;
    color: #000000;
  }
  
  .ad-card, 
  .cdn-card, 
  .feature-card, 
  .card-ad {
    border: 2px solid #000000;
  }
}

/* 超大屏幕适配 */
@media (min-width: 1920px) {
  .container {
    max-width: 1800px;
  }
}

/* Media Queries */
@media (max-width: 1200px) {
  .container {
    padding: 0 1.25rem;
  }
}

@media (max-width: 1024px) {
  .hero h1 {
    font-size: clamp(1.5rem, 4vw, 2.25rem);
  }
  
  .hero p {
    font-size: clamp(1rem, 2.5vw, 1.125rem);
  }
  
  .section-title h2 {
    font-size: clamp(1.375rem, 4vw, 1.875rem);
  }
  
  .payment-info-grid {
    gap: clamp(1rem, 3vw, 1.5625rem);
  }
}

@media (max-width: 992px) {
  .cdn-providers {
    grid-template-columns: repeat(auto-fill, minmax(min(300px, 100%), 1fr));
  }
}

@media (max-width: 768px) {
  header {
    padding: 0.9375rem 0;
  }
  
  .header-container {
    flex-direction: row;
    justify-content: space-between;
    padding: 0 1rem;
  }
  
  nav ul {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background-color: var(--secondary-color);
    flex-direction: column;
    padding: 1.25rem;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    z-index: 99;
    gap: 0;
  }
  
  nav ul.active {
    display: flex;
  }
  
  nav ul li {
    margin: 0.625rem 0;
    text-align: center;
  }
  
  .mobile-menu {
    display: block;
  }
  
  .hero {
    padding: clamp(2.5rem, 6vw, 3.75rem) 0;
  }
  
  .hero h1 {
    font-size: clamp(1.5rem, 4vw, 2rem);
  }
  
  .hero p {
    font-size: clamp(1rem, 2.5vw, 1.0625rem);
  }
  
  .hero-btn {
    padding: 0.75rem 1.5625rem;
    font-size: 0.9375rem;
  }
  
  .section {
    padding: clamp(2rem, 5vw, 3.75rem) 0;
  }
  
  .section-title h2 {
    font-size: clamp(1.375rem, 4vw, 1.75rem);
  }
  
  .ad-options {
    grid-template-columns: 1fr;
  }
  
  .payment-methods,
  .payment-details {
    padding: clamp(1rem, 3vw, 1.875rem);
  }
  
  .payment-info-grid {
    grid-template-columns: 1fr;
  }
  
  .qr-code {
    width: clamp(140px, 35vw, 180px);
    height: clamp(140px, 35vw, 180px);
  }
  
  .process-step {
    flex-direction: column;
  }
  
  .step-number {
    margin-right: 0;
    margin-bottom: clamp(1rem, 3vw, 1.5625rem);
  }
  
  .process-step:not(:last-child)::after {
    left: clamp(1.5rem, 4vw, 2.1875rem);
    top: clamp(2.5rem, 6vw, 4.375rem);
    bottom: -clamp(1.5rem, 4vw, 2.5rem);
    height: clamp(1.5rem, 4vw, 2.5rem);
    width: 0.1875rem;
  }
  
  .guidelines-grid {
    grid-template-columns: 1fr;
  }
  
  .link-ad-features .container {
    grid-template-columns: 1fr;
  }
  
  .process-flow {
    flex-direction: column;
  }
  
  .flow-arrow {
    transform: rotate(90deg);
    margin: 0.9375rem 0;
  }
  
  .flow-step {
    margin: 0.9375rem 0;
  }
  
  .contact-form-container {
    padding: clamp(1rem, 3vw, 1.875rem);
  }
  
  .form-title h3 {
    font-size: clamp(1.375rem, 4vw, 1.75rem);
  }
  
  .contact-form {
    grid-template-columns: 1fr;
  }
  
  .card-ads {
    grid-template-columns: 1fr;
  }
  
  .ad-banner div {
    flex-direction: column;
  }
  
  .ad-banner div a {
    margin-bottom: 0.625rem;
  }
}

@media (max-width: 576px) {
  .hero {
    padding: clamp(2rem, 5vw, 2.5rem) 0;
  }
  
  .section {
    padding: clamp(1.5rem, 4vw, 2.5rem) 0;
  }
  
  .section-title h2 {
    font-size: clamp(1.25rem, 4vw, 1.625rem);
  }
  
  .cdn-providers {
    grid-template-columns: 1fr;
  }
  
  .feature-grid {
    grid-template-columns: 1fr;
  }
  
  /* 移动端表格优化 */
  .comparison-table {
    min-width: 500px;
    font-size: 0.75rem;
  }
  
  .comparison-table th, 
  .comparison-table td {
    padding: 0.2rem;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: clamp(1.375rem, 4vw, 1.75rem);
  }
  
  .hero p {
    font-size: 0.9375rem;
  }
  
  .section-title h2 {
    font-size: clamp(1.25rem, 4vw, 1.625rem);
  }
  
  .ad-card, .card-ad {
    padding: clamp(1rem, 3vw, 1.5625rem);
  }
  
  .ad-card h3, .card-ad h3 {
    font-size: clamp(1.125rem, 3vw, 1.375rem);
  }
  
  .payment-methods,
  .payment-details {
    padding: 1.25rem;
  }
  
  .step-content {
    padding: clamp(1rem, 3vw, 1.5625rem);
  }
  
  .example-container {
    padding: clamp(1rem, 3vw, 1.5625rem);
  }
  
  .contact-form-container {
    padding: clamp(1rem, 3vw, 1.5625rem);
  }
  
  .form-title h3 {
    font-size: clamp(1.25rem, 4vw, 1.5rem);
  }
  
  .card {
    padding: clamp(1rem, 3vw, 1.5625rem);
  }
  
  /* 超小屏幕表格优化 */
  .comparison-table {
    min-width: 300px;
    font-size: 0.7rem;
  }
  
  .comparison-table th, 
  .comparison-table td {
    padding: 0.1rem;
  }
}

/* 超小屏幕设备（如折叠手机） */
@media (max-width: 360px) {
  .container {
    padding: 0 0.75rem;
  }
  
  .hero-btn {
    display: block;
    margin: 0.5rem auto;
    width: 90%;
  }
  
  .step-number {
    width: 3rem;
    height: 3rem;
    font-size: 1.125rem;
  }
  
  /* 超小屏幕表格优化 */
  .comparison-table {
    min-width: 300px;
  }
}

/* 横屏模式优化 */
@media (max-height: 500px) and (orientation: landscape) {
  .hero {
    padding: 2rem 0;
  }
  
  .section {
    padding: 2rem 0;
  }
  
  .hero h1 {
    font-size: 1.5rem;
  }
  
  .hero p {
    font-size: 0.875rem;
    margin-bottom: 1rem;
  }
}