/* ── Variables ── */
:root {
  --color-primary: #2D7FF9;
  --color-primary-dark: #1A5FCC;
  --color-bg: #FAFBFC;
  --color-surface: #FFFFFF;
  --color-text: #1F2937;
  --color-text-light: #6B7280;
  --color-border: #E5E7EB;
  --color-code-bg: #F3F4F6;
  --color-success: #10B981;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: "SF Mono", "Fira Code", "Fira Mono", Menlo, Consolas, monospace;
  --max-width: 720px;
  --radius: 8px;
}

/* ── Reset ── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

/* ── Base ── */
html {
  scroll-behavior: smooth;
}

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

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

a:hover {
  text-decoration: underline;
}

a:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: 2px;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* ── Hero ── */
.hero {
  background: linear-gradient(135deg, #1E40AF 0%, var(--color-primary) 50%, #3B82F6 100%);
  color: white;
  padding: 80px 0 64px;
  text-align: center;
}

.hero h1 {
  font-size: 2.75rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

.tagline {
  font-size: 1.2rem;
  opacity: 0.9;
  max-width: 480px;
  margin: 0 auto;
  line-height: 1.5;
}

/* ── Sections ── */
section {
  padding: 64px 0;
}

section + section {
  border-top: 1px solid var(--color-border);
}

h2 {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.section-intro {
  color: var(--color-text-light);
  margin-bottom: 32px;
  font-size: 1.05rem;
}

/* ── Steps ── */
.steps {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.step {
  display: flex;
  gap: 20px;
  align-items: flex-start;
}

.step-number {
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--color-primary);
  color: white;
  font-weight: 700;
  font-size: 1.1rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.step-content {
  flex: 1;
}

.step-content h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 6px;
}

.step-content p {
  margin-bottom: 12px;
}

.step-note {
  font-size: 0.9rem;
  color: var(--color-text-light);
  font-style: italic;
}

/* ── Code blocks ── */
.code-block {
  position: relative;
  background: var(--color-code-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 12px 16px;
  margin: 12px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.code-block code {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: var(--color-text);
  word-break: break-all;
}

.copy-btn {
  flex-shrink: 0;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: 6px 14px;
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  color: var(--color-text-light);
  transition: all 0.15s ease;
}

.copy-btn:hover {
  background: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
}

.copy-btn:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.copy-btn.copied {
  background: var(--color-success);
  color: white;
  border-color: var(--color-success);
}

/* ── Inline code ── */
p code, li code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  background: var(--color-code-bg);
  padding: 2px 6px;
  border-radius: 4px;
  border: 1px solid var(--color-border);
}

/* ── Details/FAQ ── */
details {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  margin-bottom: 12px;
  overflow: hidden;
}

details summary {
  padding: 16px 20px;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

details summary::after {
  content: "+";
  font-size: 1.25rem;
  color: var(--color-text-light);
  transition: transform 0.2s ease;
}

details[open] summary::after {
  content: "\2212";
}

details summary::-webkit-details-marker {
  display: none;
}

details summary:hover {
  background: var(--color-bg);
}

.details-content {
  padding: 0 20px 16px;
}

.details-content p {
  margin-bottom: 8px;
}

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

/* ── After Setup ── */
.after-setup {
  margin-top: 48px;
  background: linear-gradient(135deg, #ECFDF5, #F0FDF4);
  border: 1px solid #A7F3D0;
  border-radius: var(--radius);
  padding: 24px;
}

.after-setup h3 {
  color: #065F46;
  font-size: 1.1rem;
  margin-bottom: 8px;
}

.example-prompts {
  list-style: none;
  margin-top: 12px;
}

.example-prompts li {
  padding: 8px 0;
  color: var(--color-text-light);
  font-style: italic;
}

.example-prompts li::before {
  content: "\201C";
}

.example-prompts li::after {
  content: "\201D";
}

/* ── Feature Grid ── */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.feature-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 20px;
}

.feature-card h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 6px;
}

.feature-card p {
  font-size: 0.9rem;
  color: var(--color-text-light);
  line-height: 1.5;
}

/* ── Footer ── */
footer {
  border-top: 1px solid var(--color-border);
  padding: 32px 0;
  text-align: center;
  color: var(--color-text-light);
  font-size: 0.9rem;
}

/* ── Responsive ── */
@media (max-width: 640px) {
  .hero {
    padding: 48px 0 40px;
  }

  .hero h1 {
    font-size: 2rem;
  }

  .tagline {
    font-size: 1.05rem;
  }

  .step {
    flex-direction: column;
    gap: 12px;
  }

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

  section {
    padding: 40px 0;
  }
}

/* ── Dark Mode ── */
@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #111827;
    --color-surface: #1F2937;
    --color-text: #F9FAFB;
    --color-text-light: #9CA3AF;
    --color-border: #374151;
    --color-code-bg: #1F2937;
  }

  .hero {
    background: linear-gradient(135deg, #1E3A5F 0%, #1E40AF 50%, #2563EB 100%);
  }

  .after-setup {
    background: linear-gradient(135deg, #064E3B, #065F46);
    border-color: #047857;
  }

  .after-setup h3 {
    color: #6EE7B7;
  }

  .copy-btn {
    background: var(--color-surface);
    color: var(--color-text-light);
    border-color: var(--color-border);
  }
}