:root {
  --page-bg: #f6f7f9;
  --surface: #ffffff;
  --surface-muted: #f1f3f6;
  --border: #e1e4ea;
  --text-strong: #20222a;
  --text-body: #3b3f46;
  --text-muted: #5e636d;
  --primary-gray: #2f3136;
  --accent: #10a37f;
  --accent-hover: #2fb898;
  --accent-soft: rgba(16, 163, 127, 0.12);
  --shadow-lg: 0 30px 70px rgba(29, 33, 43, 0.08);
  --shadow-md: 0 18px 48px rgba(40, 44, 54, 0.08);
  --shadow-sm: 0 10px 30px rgba(43, 47, 59, 0.05);
  --radius-xl: 28px;
  --radius-lg: 20px;
  --radius-md: 14px;
  --radius-sm: 8px;
  --font-sans: "Inter", "Helvetica Neue", Arial, sans-serif;
  --font-mono: "IBM Plex Mono", "SFMono-Regular", Menlo, monospace;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  line-height: 1.75;
  background: var(--page-bg);
  color: var(--text-body);
  -webkit-font-smoothing: antialiased;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  width: 100%;
  background: rgba(255, 255, 255, 0.96);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(14px);
}

.nav-container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0.85rem clamp(1.3rem, 4vw, 2.2rem);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.nav-brand {
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--primary-gray);
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
}

.nav-brand span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: var(--surface-muted);
  border: 1px solid var(--border);
  font-size: 0.95rem;
}

.nav-toggle {
  border: 1px solid var(--border);
  background: #ffffff;
  color: var(--primary-gray);
  border-radius: var(--radius-sm);
  padding: 0.55rem 0.75rem;
  font-size: 0.95rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  cursor: pointer;
}

.nav-toggle .nav-toggle-bars {
  width: 18px;
  height: 2px;
  background: var(--primary-gray);
  position: relative;
  display: inline-block;
}

.nav-toggle .nav-toggle-bars::before,
.nav-toggle .nav-toggle-bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: var(--primary-gray);
  transition: transform 0.2s ease;
}

.nav-toggle .nav-toggle-bars::before {
  top: -6px;
}

.nav-toggle .nav-toggle-bars::after {
  top: 6px;
}

.nav-toggle.is-open .nav-toggle-bars {
  background: transparent;
}

.nav-toggle.is-open .nav-toggle-bars::before {
  transform: translateY(6px) rotate(45deg);
}

.nav-toggle.is-open .nav-toggle-bars::after {
  transform: translateY(-6px) rotate(-45deg);
}

.nav-links {
  display: none;
  flex-direction: column;
  gap: 0.8rem;
  width: 100%;
  margin-top: 1rem;
  padding: 0.85rem 1.1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  background: #ffffff;
  box-shadow: var(--shadow-sm);
}

.nav-links.is-open {
  display: flex;
}

.nav-links a {
  color: var(--text-muted);
  font-weight: 500;
  padding: 0.35rem 0;
}

.nav-links a.is-active {
  color: var(--accent);
}

.nav-links .nav-cta {
  margin-top: 0.4rem;
  padding: 0.6rem 1rem;
  border-radius: var(--radius-sm);
  background: var(--accent);
  color: #f7fffb;
  text-align: center;
}

.nav-links .nav-cta:hover {
  box-shadow: var(--shadow-sm);
  transform: translateY(-1px);
}

h1 {
  color: var(--primary-gray);
  font-size: clamp(2.2rem, 4vw, 3rem);
  letter-spacing: -0.015em;
  margin: 0 0 0.6rem;
}

h2 {
  color: var(--primary-gray);
  margin: 3rem 0 1rem;
}

h3 {
  color: var(--primary-gray);
  margin: 2rem 0 0.8rem;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--accent-hover);
}

img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-sm);
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: clamp(2.4rem, 6vw, 3.6rem) clamp(1.4rem, 4vw, 3rem);
}

.small-container {
  max-width: 940px;
  margin: 0 auto;
  padding: clamp(2.4rem, 6vw, 3.4rem) clamp(1.4rem, 4vw, 2.6rem);
}

.breadcrumb {
  padding-bottom: 1rem;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.breadcrumb a {
  color: var(--text-muted);
}

.badge-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1.3rem;
}

.badge,
.pill {
  display: inline-flex;
  align-items: center;
  padding: 0.4rem 0.8rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--surface-muted);
  color: var(--text-muted);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.pill {
  background: var(--accent-soft);
  color: var(--accent);
  letter-spacing: 0.06em;
}

.hero {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-xl);
  padding: clamp(3.5rem, 6vw, 4.5rem);
  background: linear-gradient(120deg, #ffffff 0%, #f3f5f9 55%, #edf1f8 100%);
  box-shadow: var(--shadow-lg);
}

.hero::after {
  content: "";
  position: absolute;
  inset: auto -15% -40% 40%;
  height: 320px;
  background: radial-gradient(circle at center, rgba(51, 54, 62, 0.15), transparent 70%);
}

.hero h1 {
  font-size: clamp(2.7rem, 4.5vw, 3.6rem);
  color: var(--primary-gray);
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
}

.hero .subhead {
  font-size: 1.1rem;
  max-width: 52ch;
  color: var(--text-muted);
  margin-bottom: 2.1rem;
}

.hero p:last-child {
  margin-top: 1.6rem;
  color: var(--text-muted);
}

.meta {
  color: var(--text-muted);
  margin-bottom: 2rem;
}

.cta-buttons,
.cta-group {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.cta-button,
.cta-group a.btn,
.cta-group .btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.8rem;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  background: var(--accent);
  color: #f7fffb;
  font-weight: 600;
  letter-spacing: 0.01em;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.cta-button.secondary,
.cta-group .btn-outline {
  background: #ffffff;
  color: var(--primary-gray);
  border-color: var(--border);
}

.cta-button:hover,
.cta-group a.btn:hover,
.cta-group .btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.section,
.intro,
.card,
.requirements,
.alternative-method,
.compatibility,
.troubleshooting,
.alert,
.callout,
.toc,
.release,
.grid-card,
.highlight,
.cna-surface,
.cta-section {
  background: var(--surface);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  padding: clamp(1.8rem, 4vw, 2.6rem);
}

.section {
  margin-top: clamp(2.4rem, 5vw, 3.5rem);
}

.section h2 {
  color: var(--primary-gray);
  font-size: clamp(2rem, 3.5vw, 2.5rem);
  letter-spacing: -0.015em;
  margin-top: 0;
}

.section p,
.intro p,
.card p,
.requirements p,
.alternative-method p,
.callout p,
.toc p,
.release p,
.grid-card p,
.highlight p,
.cna-surface p,
.cta-section p {
  color: var(--text-muted);
}

.feature-grid,
.highlight-grid,
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: clamp(1.4rem, 3vw, 2rem);
  margin-top: 2rem;
}

.feature-card,
.highlight,
.grid-card {
  background: var(--surface-muted);
  border-radius: var(--radius-md);
  border: 1px solid rgba(209, 213, 220, 0.6);
  padding: 1.6rem;
}

.feature-card h3,
.grid-card h3,
.highlight strong,
.faq-question,
.step h3,
.step-title,
.card h3,
.release strong {
  color: var(--primary-gray);
  margin-top: 0;
}

.tabs {
  display: inline-flex;
  gap: 0.55rem;
  padding: 0.4rem;
  border-radius: 999px;
  background: var(--surface-muted);
  border: 1px solid var(--border);
  margin-bottom: 1.8rem;
}

.tab {
  padding: 0.65rem 1.45rem;
  border-radius: 999px;
  cursor: pointer;
  font-weight: 500;
  color: var(--text-muted);
  transition: background 0.2s ease, color 0.2s ease;
}

.tab.active {
  background: var(--accent-soft);
  color: var(--accent);
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
}

.tab-content ol,
.tab-content ul {
  color: var(--text-muted);
  padding-left: 1.3rem;
}

.comparison-table,
.compare-table,
.spec-table {
  width: 100%;
  border-collapse: collapse;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  overflow: hidden;
  background: #fff;
  margin-top: 2rem;
}

.comparison-table th,
.compare-table th,
.spec-table th,
.comparison-table td,
.compare-table td,
.spec-table td {
  padding: 1rem 1.1rem;
  border-bottom: 1px solid var(--border);
  text-align: left;
  color: var(--text-muted);
}

.comparison-table th,
.compare-table th,
.spec-table th {
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  background: var(--surface-muted);
}

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

.requirements,
.alternative-method,
.compatibility,
.alert {
  background: var(--surface-muted);
  border: 1px solid rgba(209, 213, 220, 0.7);
}

.callout,
.tip {
  background: var(--accent-soft);
  border: 1px solid rgba(16, 163, 127, 0.3);
  border-radius: var(--radius-md);
  padding: 1.3rem 1.5rem;
  margin: 1.8rem 0;
  color: var(--text-body);
}

.step {
  display: flex;
  gap: 1rem;
  margin: 1.8rem 0;
  padding: 1.6rem 1.9rem;
  background: var(--surface);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}

.step-number {
  min-width: 40px;
  height: 40px;
  border-radius: 12px;
  background: var(--surface-muted);
  border: 1px solid var(--border);
  color: var(--primary-gray);
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
}

.step ul,
.step ol {
  padding-left: 1.2rem;
  color: var(--text-muted);
}

.faq-item {
  margin: 1.5rem 0;
}

.faq-question {
  margin-bottom: 0.35rem;
  font-weight: 600;
}

.faq-answer,
.faq-item p,
li {
  color: var(--text-muted);
}

.code-block,
pre {
  background: #23262d;
  color: #f5f5f5;
  padding: 1.2rem 1.4rem;
  border-radius: var(--radius-md);
  overflow-x: auto;
  font-family: var(--font-mono);
}

code {
  font-family: var(--font-mono);
  background: rgba(31, 32, 37, 0.08);
  padding: 0.1rem 0.35rem;
  border-radius: 4px;
}

.toc {
  background: var(--surface-muted);
  border: 1px solid rgba(209, 213, 220, 0.7);
}

.release {
  margin: 1.4rem 0;
}

.cta-section {
  text-align: center;
  margin: 3rem 0;
  box-shadow: var(--shadow-lg);
}

.note {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-top: 0.8rem;
}

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

.footer-link,
.page-footer {
  margin-top: 3rem;
  padding-top: 1.6rem;
  border-top: 1px solid #ddd;
  text-align: center;
  color: #666;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

ul {
  padding-left: 1.2rem;
}

@media (max-width: 780px) {
  .hero {
    padding: 2.6rem 1.8rem;
  }

  .cta-buttons,
  .cta-group {
    flex-direction: column;
    align-items: stretch;
  }

  .cta-button,
  .cta-group a.btn,
  .cta-group .btn {
    width: 100%;
  }

  .step {
    flex-direction: column;
  }

  .step-number {
    width: 44px;
    height: 44px;
  }

  .feature-grid,
  .highlight-grid,
  .grid {
    grid-template-columns: 1fr;
  }
}

@media (min-width: 768px) {
  .nav-container {
    flex-wrap: nowrap;
  }

  .nav-toggle {
    display: none;
  }

  .nav-links {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 1.4rem;
    width: auto;
    margin-top: 0;
    padding: 0;
    border: none;
    box-shadow: none;
    background: transparent;
  }

  .nav-links .nav-cta {
    margin-top: 0;
    padding: 0.55rem 1.1rem;
  }
}