:root {
  --primary: #004A99;
  --secondary: #F0F4F8;
  --bg-color: #ffffff;
  --text-main: #171717;
  --text-muted: #4a4a4a;
  --border-color: #e2e8f0;
  --white: #ffffff;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --border-radius: 12px;
  --font-sans: 'Inter', 'Roboto', -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1);
}

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

html {
  scroll-behavior: smooth;
}

body {
  background-color: var(--bg-color);
  color: var(--text-main);
  font-family: var(--font-sans);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  position: relative;
}

body::before {
  content: "";
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  opacity: 0.02;
  pointer-events: none;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3仿真%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.65' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
  z-index: 9999;
}

.container {
  width: 100%;
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Typography */
h1, h2, h3, h4 {
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 1.5rem;
  letter-spacing: -0.02em;
}

h1 { font-size: 2.5rem; color: var(--text-main); }
h2 { font-size: 1.85rem; margin-top: 2.5rem; }
h3 { font-size: 1.4rem; }

p { margin-bottom: 1.25rem; }

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

a:hover {
  opacity: 0.8;
}

/* Header & Nav */
header {
  padding: 1.5rem 0;
  border-bottom: 1px solid var(--secondary);
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(10px);
  position: sticky;
  top: 0;
  z-index: 100;
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-weight: 900;
  font-size: 1.25rem;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 1px;
}

/* Bento Grid System */
.bento-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
  margin: 3rem 0;
}

.bento-card {
  background: var(--secondary);
  padding: 2rem;
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.bento-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
}

/* CTAs & Buttons */
.cta-button {
  display: inline-block;
  background-color: var(--primary);
  color: var(--white);
  padding: 14px 28px;
  border-radius: 50px;
  font-weight: 600;
  text-align: center;
  border: none;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: 0 4px 14px rgba(0, 74, 153, 0.25);
}

.cta-button:hover {
  transform: scale(1.03);
  box-shadow: 0 6px 20px rgba(0, 74, 153, 0.35);
  opacity: 1;
}

.cta-secondary {
  background-color: var(--secondary);
  color: var(--primary);
  border: 1px solid var(--primary);
}

/* Comparison Table */
.table-container {
  overflow-x: auto;
  margin: 2rem 0;
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
}

table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
}

th {
  background-color: var(--secondary);
  padding: 16px;
  font-weight: 700;
  color: var(--primary);
  border-bottom: 2px solid var(--border-color);
}

td {
  padding: 16px;
  border-bottom: 1px solid var(--border-color);
  font-size: 0.95rem;
}

tr:last-child td { border-bottom: none; }

/* Article Content */
article {
  max-width: 800px;
  margin: 0 auto;
  padding: 40px 0;
}

.meta-info {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 2rem;
  display: flex;
  gap: 15px;
}

.in-content-ads {
  background: var(--secondary);
  padding: 20px;
  margin: 30px 0;
  border-radius: var(--border-radius);
  text-align: center;
  font-style: italic;
  font-size: 0.8rem;
  color: var(--text-muted);
  border: 1px dashed var(--primary);
}

/* Sidebar Elements */
.sidebar {
  padding: 20px;
  background: var(--secondary);
  border-radius: var(--border-radius);
}

/* Internal Links List */
.internal-links {
  list-style: none;
  margin: 20px 0;
  padding: 20px;
  background: #f8fafc;
  border-left: 4px solid var(--primary);
}

.internal-links li {
  margin-bottom: 10px;
}

/* FAQ Schema Styling */
.faq-section {
  margin-top: 4rem;
}

.faq-item {
  border-bottom: 1px solid var(--border-color);
  padding: 20px 0;
}

.faq-question {
  font-weight: 700;
  font-size: 1.1rem;
  margin-bottom: 10px;
  color: var(--primary);
}

/* Mobile Adjustments */
@media (max-width: 768px) {
  h1 { font-size: 2rem; }
  h2 { font-size: 1.5rem; }
  .bento-grid { grid-template-columns: 1fr; }
  .cta-button { width: 100%; box-sizing: border-box; }
  
  td, th {
    padding: 12px 8px;
    font-size: 0.85rem;
  }
}

/* Footer */
footer {
  background: var(--secondary);
  padding: 4rem 0;
  margin-top: 5rem;
  border-top: 1px solid var(--border-color);
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 40px;
}

.footer-heading {
  font-weight: 700;
  margin-bottom: 1.5rem;
  color: var(--primary);
}

/* Image styling */
img {
  max-width: 100%;
  height: auto;
  border-radius: var(--border-radius);
  margin: 1.5rem 0;
}

/* High Contrast & Accessibility */
:focus {
  outline: 3px solid rgba(0, 74, 153, 0.4);
  outline-offset: 2px;
}

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

.badge-new {
  background: var(--primary);
  color: white;
  padding: 4px 10px;
  border-radius: 4px;
  font-size: 0.7rem;
  font-weight: bold;
  vertical-align: middle;
  margin-left: 10px;
}