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

/* Navigation Bar */
.top-nav {
  background: white;
  padding: 20px 40px;
  border-bottom: 2px solid #f5f7fa;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: #2fb8c6;
  text-decoration: none;
  font-weight: 600;
  transition: all 0.3s ease;
  padding: 8px 16px;
  border-radius: 8px;
}

.back-link:hover {
  background: #f5f7fa;
  color: #0b1f33;
  transform: translateX(-3px);
}

.back-link::before {
  content: "←";
  font-size: 1.2em;
}

.blog-logo {
  font-weight: 700;
  color: #0b1f33;
  font-size: 1.1em;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, sans-serif;
  line-height: 1.7;
  color: #111827;
  background: linear-gradient(135deg, #0b1f33 0%, #3a5a78 100%);
  min-height: 100vh;
  padding: 20px;
}

.container {
  max-width: 900px;
  margin: 0 auto;
  background: white;
  border-radius: 16px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
  overflow: hidden;
}

header {
  background: linear-gradient(135deg, #0b1f33 0%, #0f172a 100%);
  color: white;
  padding: 60px 40px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

header::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><defs><pattern id="grid" width="20" height="20" patternUnits="userSpaceOnUse"><path d="M 20 0 L 0 0 0 20" fill="none" stroke="rgba(255,255,255,0.05)" stroke-width="1"/></pattern></defs><rect width="100" height="100" fill="url(%23grid)"/></svg>');
  opacity: 0.3;
}

header > * {
  position: relative;
  z-index: 1;
}

h1 {
  font-size: 2.5em;
  font-weight: 800;
  margin-bottom: 15px;
  letter-spacing: -0.5px;
}

h3.subtitle {
  font-size: 1.3em;
  font-weight: 400;
  color: #cbd5e0;
  margin-bottom: 20px;
}

.author {
  font-style: italic;
  color: #a0aec0;
  font-size: 0.95em;
}

.meta-info {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin-top: 15px;
  font-size: 0.9em;
}

.meta-item {
  display: flex;
  align-items: center;
  gap: 5px;
}

article {
  padding: 50px 40px;
}

h2 {
  font-size: 1.8em;
  font-weight: 700;
  color: #0b1f33;
  margin: 40px 0 20px;
  padding-bottom: 10px;
  border-bottom: 3px solid #2fb8c6;
}

h3 {
  font-size: 1.4em;
  font-weight: 600;
  color: #0b1f33;
  margin: 30px 0 15px;
}

h4 {
  font-size: 1.2em;
  font-weight: 600;
  color: #3a5a78;
  margin: 25px 0 12px;
}

p {
  margin-bottom: 20px;
  font-size: 1.05em;
  color: #6b7280;
}

blockquote {
  background: linear-gradient(135deg, #f5f7fa 0%, #e5e9ef 100%);
  border-left: 5px solid #2fb8c6;
  padding: 20px 30px;
  margin: 30px 0;
  font-style: italic;
  font-size: 1.1em;
  color: #0b1f33;
  border-radius: 8px;
}

ul,
ol {
  margin: 20px 0 20px 30px;
}

li {
  margin-bottom: 12px;
  color: #6b7280;
  line-height: 1.7;
}

strong {
  color: #0b1f33;
  font-weight: 600;
}

hr {
  border: none;
  height: 2px;
  background: linear-gradient(90deg, transparent, #e2e8f0, transparent);
  margin: 40px 0;
}

.image-container {
  margin: 35px 0;
  text-align: center;
  background: #f5f7fa;
  padding: 30px;
  border-radius: 12px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
}

img {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
}

.image-caption {
  margin-top: 15px;
  font-size: 0.9em;
  color: #718096;
  font-style: italic;
}

a {
  color: #2fb8c6;
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s ease;
}

a:hover {
  color: #3a5a78;
  text-decoration: underline;
}

.agent-list {
  background: #f5f7fa;
  padding: 25px;
  border-radius: 10px;
  margin: 25px 0;
}

.agent-list li {
  padding: 10px 0;
}

.info-box {
  background: linear-gradient(135deg, #e6f7f9 0%, #d1f0f4 100%);
  border-left: 4px solid #2fb8c6;
  padding: 20px 25px;
  margin: 25px 0;
  border-radius: 8px;
}

.info-box h4 {
  color: #0b1f33;
  margin-top: 0;
}

.warning-box {
  background: linear-gradient(135deg, #fffbeb 0%, #fef3c7 100%);
  border-left: 4px solid #f59e0b;
  padding: 20px 25px;
  margin: 25px 0;
  border-radius: 8px;
}

.warning-box h4 {
  color: #92400e;
  margin-top: 0;
}

.comparison-table {
  width: 100%;
  margin: 30px 0;
  border-collapse: collapse;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
  border-radius: 8px;
  overflow: hidden;
}

.comparison-table th {
  background: linear-gradient(135deg, #0b1f33 0%, #3a5a78 100%);
  color: white;
  padding: 15px;
  text-align: left;
  font-weight: 600;
}

.comparison-table td {
  padding: 15px;
  border-bottom: 1px solid #e2e8f0;
  background: white;
}

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

.comparison-table tr:nth-child(even) td {
  background: #f5f7fa;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
  margin: 30px 0;
}

.stat-card {
  background: linear-gradient(135deg, #2fb8c6 0%, #3a5a78 100%);
  color: white;
  padding: 25px;
  border-radius: 12px;
  text-align: center;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.15);
}

.stat-number {
  font-size: 2.5em;
  font-weight: 800;
  margin-bottom: 10px;
}

.stat-label {
  font-size: 0.95em;
  opacity: 0.9;
}

.code-block {
  background: #0f172a;
  color: #e2e8f0;
  padding: 20px;
  border-radius: 8px;
  margin: 25px 0;
  overflow-x: auto;
  font-family: "Courier New", monospace;
  font-size: 0.9em;
  line-height: 1.6;
}

.highlight {
  background: linear-gradient(120deg, #fef3c7 0%, #fed7aa 100%);
  padding: 2px 6px;
  border-radius: 3px;
  font-weight: 500;
}

footer {
  background: #0b1f33;
  color: #a0aec0;
  padding: 30px 40px;
  text-align: center;
  font-size: 0.9em;
}

/* Share Section */
.share-section {
  margin-top: 20px;
}

.share-section p {
  color: #cbd5e0;
  margin-bottom: 15px;
  font-size: 1em;
}

.share-buttons {
  display: flex;
  justify-content: center;
  gap: 15px;
  flex-wrap: wrap;
}

.share-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  background: rgba(47, 184, 198, 0.1);
  color: #2fb8c6;
  border: 1px solid #2fb8c6;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.9em;
  transition: all 0.3s ease;
  cursor: pointer;
}

.share-btn:hover {
  background: #2fb8c6;
  color: white;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(47, 184, 198, 0.3);
  text-decoration: none;
}

.share-btn svg {
  width: 18px;
  height: 18px;
  fill: currentColor;
}

.share-btn.copied {
  background: #10b981;
  border-color: #10b981;
  color: white;
}

@media (max-width: 768px) {
  body {
    padding: 10px;
  }

  header,
  article,
  footer {
    padding: 30px 20px;
  }

  h1 {
    font-size: 1.8em;
  }

  h2 {
    font-size: 1.5em;
  }

  .stats-grid {
    grid-template-columns: 1fr;
  }
}

img {
  width: 100%;
  height: 400px;
  object-fit: cover;
}

/* Reading Progress Bar */
#reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 4px;
  width: 0%;
  background: linear-gradient(90deg, #4f46e5, #06b6d4);
  z-index: 9999;
  transition: width 0.1s ease-out;
}

/* Avoid content hiding under fixed bar */
body {
  padding-top: 4px;
}