:root {
  --color-bg: #ffffff;
  --color-surface: #f8fafc;
  --color-text: #334155;
  --color-heading: #0f172a;
  --color-muted: #64748b;
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-primary-light: #eff6ff;
  --color-accent: #f59e0b;
  --color-border: #e2e8f0;
  --color-success: #10b981;
  --color-danger: #ef4444;
  --radius-sm: 6px;
  --radius: 12px;
  --radius-lg: 16px;
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.05);
  --shadow: 0 4px 6px -1px rgba(15, 23, 42, 0.07), 0 2px 4px -2px rgba(15, 23, 42, 0.05);
  --shadow-lg: 0 10px 15px -3px rgba(15, 23, 42, 0.08), 0 4px 6px -4px rgba(15, 23, 42, 0.04);
  --max-width: 1100px;
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.65;
  font-size: 16px;
}

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

a:hover {
  text-decoration: underline;
}

img {
  max-width: 100%;
  height: auto;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1rem;
}

/* Header - mobile first */
.site-header {
  background: rgba(255, 255, 255, 0.96);
  border-bottom: 1px solid var(--color-border);
  padding: 0.75rem 0;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(8px);
}

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

.logo {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--color-heading);
  letter-spacing: -0.02em;
  white-space: nowrap;
}

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

/* Menu toggle - visible by default on mobile */
.menu-toggle {
  display: block;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  margin-right: -0.5rem;
  color: var(--color-heading);
  line-height: 0;
}

.menu-toggle svg {
  width: 26px;
  height: 26px;
}

/* Nav - hidden by default on mobile */
.nav {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  flex-direction: column;
  padding: 0.5rem 1rem;
  box-shadow: var(--shadow-lg);
  gap: 0;
}

.nav.open {
  display: flex;
}

.nav a {
  display: block;
  width: 100%;
  padding: 0.875rem 0;
  color: var(--color-muted);
  font-weight: 600;
  font-size: 1rem;
  border-bottom: 1px solid var(--color-border);
  transition: color 0.15s ease;
}

.nav a:last-child {
  border-bottom: none;
}

.nav a:hover,
.nav a.active {
  color: var(--color-primary);
  text-decoration: none;
}

/* Desktop nav */
@media (min-width: 769px) {
  .menu-toggle {
    display: none;
  }

  .nav {
    display: flex !important;
    position: static;
    flex-direction: row;
    align-items: center;
    gap: 1.75rem;
    padding: 0;
    border: none;
    box-shadow: none;
    background: transparent;
  }

  .nav a {
    width: auto;
    padding: 0;
    border: none;
    font-size: 0.95rem;
  }

  .nav a:hover {
    color: var(--color-heading);
  }
}

/* Hero */
.hero {
  padding: 3rem 0 2.5rem;
  text-align: center;
  background: linear-gradient(180deg, #f8fafc 0%, #ffffff 100%);
  border-bottom: 1px solid var(--color-border);
}

.hero h1 {
  font-size: 2rem;
  color: var(--color-heading);
  line-height: 1.2;
  margin-bottom: 1.25rem;
  letter-spacing: -0.02em;
}

.hero p {
  font-size: 1.05rem;
  color: var(--color-muted);
  max-width: 640px;
  margin: 0 auto 1.5rem;
}

.hero .btn {
  font-size: 1rem;
  padding: 0.9rem 1.75rem;
}

/* Content */
.content {
  padding: 2.5rem 0 4rem;
}

.content h2 {
  font-size: 1.6rem;
  color: var(--color-heading);
  margin-bottom: 1.25rem;
  letter-spacing: -0.01em;
}

.content p {
  margin-bottom: 1.25rem;
  color: var(--color-text);
}

/* Article */
.article-header {
  margin-bottom: 2rem;
  padding-bottom: 1.25rem;
  border-bottom: 1px solid var(--color-border);
}

.article-header h1 {
  font-size: 1.85rem;
  color: var(--color-heading);
  line-height: 1.2;
  margin-bottom: 0.75rem;
  letter-spacing: -0.02em;
}

.article-meta {
  color: var(--color-muted);
  font-size: 0.9rem;
}

.article-body h2 {
  font-size: 1.4rem;
  color: var(--color-heading);
  margin: 2.5rem 0 1rem;
  letter-spacing: -0.01em;
}

.article-body h3 {
  font-size: 1.15rem;
  color: var(--color-heading);
  margin: 1.75rem 0 0.6rem;
}

.article-body p {
  margin-bottom: 1.1rem;
}

.article-body ul,
.article-body ol {
  margin: 0 0 1.25rem 1.25rem;
}

.article-body li {
  margin-bottom: 0.5rem;
}

/* Cards */
.card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  margin-bottom: 1.25rem;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.card:hover {
  box-shadow: var(--shadow);
  transform: translateY(-2px);
}

.card h3 {
  margin-top: 0;
  margin-bottom: 0.5rem;
  font-size: 1.2rem;
  color: var(--color-heading);
}

.card h3 a {
  color: inherit;
}

.card h3 a:hover {
  color: var(--color-primary);
}

.card p:last-child {
  margin-bottom: 0;
}

.badge {
  display: inline-block;
  background: var(--color-primary-light);
  color: var(--color-primary-dark);
  font-size: 0.7rem;
  font-weight: 700;
  padding: 0.3rem 0.65rem;
  border-radius: 999px;
  margin-bottom: 0.65rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.pros-cons {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
  margin: 1rem 0;
  padding: 1rem;
  background: var(--color-surface);
  border-radius: var(--radius-sm);
}

.pros-cons h4 {
  font-size: 0.9rem;
  margin-bottom: 0.6rem;
  color: var(--color-heading);
}

.pros-cons ul {
  margin: 0 0 0 1.1rem;
  font-size: 0.9rem;
}

.pros-cons li {
  margin-bottom: 0.35rem;
}

/* Buttons */
.btn {
  display: inline-block;
  background: var(--color-primary);
  color: #fff;
  font-weight: 600;
  padding: 0.75rem 1.4rem;
  border-radius: var(--radius-sm);
  text-decoration: none;
  text-align: center;
  transition: background 0.15s ease, transform 0.1s ease;
  border: none;
  cursor: pointer;
}

.btn:hover {
  background: var(--color-primary-dark);
  text-decoration: none;
  transform: translateY(-1px);
}

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

.btn-outline:hover {
  background: var(--color-primary);
  color: #fff;
}

.btn-block {
  display: block;
  width: 100%;
  margin-top: 1.1rem;
}

/* Comparison table */
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.25rem 0;
  font-size: 0.9rem;
  box-shadow: var(--shadow-sm);
  border-radius: var(--radius);
  overflow: hidden;
}

.comparison-table th,
.comparison-table td {
  border: 1px solid var(--color-border);
  padding: 0.75rem;
  text-align: left;
}

.comparison-table th {
  background: var(--color-surface);
  font-weight: 700;
  color: var(--color-heading);
}

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

/* CTA boxes */
.cta-box {
  background: var(--color-primary-light);
  border: 1px solid #dbeafe;
  border-radius: var(--radius);
  padding: 1.5rem;
  margin: 2rem 0;
  text-align: center;
}

.cta-box h3 {
  margin-top: 0;
  color: var(--color-heading);
  font-size: 1.25rem;
}

.cta-box p {
  margin-bottom: 1rem;
  color: var(--color-text);
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 2rem 0;
  color: var(--color-muted);
  font-size: 0.85rem;
  text-align: center;
  background: var(--color-surface);
}

.disclaimer {
  font-size: 0.75rem;
  color: var(--color-muted);
  margin-top: 0.75rem;
  max-width: 680px;
  margin-left: auto;
  margin-right: auto;
}

/* Utility */
.text-center {
  text-align: center;
}

.mb-2 {
  margin-bottom: 0.5rem;
}

.mt-2 {
  margin-top: 0.5rem;
}

/* Larger screens */
@media (min-width: 640px) {
  .container {
    padding: 0 1.25rem;
  }

  .hero {
    padding: 4rem 0 3rem;
  }

  .hero h1 {
    font-size: 2.5rem;
  }

  .hero p {
    font-size: 1.15rem;
  }

  .article-header h1 {
    font-size: 2.25rem;
  }

  .article-body h2 {
    font-size: 1.6rem;
  }

  .pros-cons {
    grid-template-columns: 1fr 1fr;
    padding: 1.25rem;
  }

  .comparison-table {
    font-size: 0.95rem;
  }

  .comparison-table th,
  .comparison-table td {
    padding: 0.85rem;
  }
}