:root {
  --color-bg: #faf9f6;
  --color-surface: #ffffff;
  --color-surface-elevated: #f4f2ed;
  --color-text: #1c1917;
  --color-text-muted: #57534e;
  --color-primary: #8b5cf6;
  --color-primary-dark: #6d28d9;
  --color-border: #e7e5e4;
  --color-callout-bg: #fef3c7;
  --color-callout-border: #d97706;
  --color-callout-text: #92400e;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --max-width: 760px;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
}

*, *::before, *::after {
  box-sizing: border-box;
}

html {
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.65;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

a {
  color: var(--color-primary-dark);
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: color 0.15s ease;
}

a:hover, a:focus-visible {
  color: var(--color-primary);
}

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

.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--color-text);
  color: #ffffff;
  padding: 8px 16px;
  z-index: 1000;
  text-decoration: none;
  font-weight: 600;
  border-radius: 0 0 var(--radius-sm) 0;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 0;
}

/* Header & Navigation */
.site-header {
  background-color: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  padding: 1rem 1.5rem;
}

.header-container {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.brand-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.brand-title:hover {
  text-decoration: none;
}

.site-nav ul {
  display: flex;
  list-style: none;
  margin: 0;
  padding: 0;
  gap: 1.25rem;
}

.site-nav a {
  color: var(--color-text-muted);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.95rem;
}

.site-nav a:hover,
.site-nav a[aria-current="page"] {
  color: var(--color-text);
  text-decoration: underline;
  text-underline-offset: 4px;
}

.site-nav a[aria-current="page"] {
  font-weight: 600;
}

/* Main Container */
.page-container {
  max-width: var(--max-width);
  margin: 2rem auto;
  padding: 0 1.5rem;
  flex: 1;
  width: 100%;
}

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  box-shadow: var(--shadow-sm);
}

@media (max-width: 640px) {
  .card {
    padding: 1.5rem;
  }
}

/* Typography */
h1 {
  font-size: 2rem;
  font-weight: 800;
  line-height: 1.25;
  margin-top: 0;
  margin-bottom: 0.5rem;
  letter-spacing: -0.02em;
}

h2 {
  font-size: 1.35rem;
  font-weight: 700;
  line-height: 1.3;
  margin-top: 2rem;
  margin-bottom: 0.75rem;
  color: var(--color-text);
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 0.4rem;
}

h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-top: 1.5rem;
  margin-bottom: 0.5rem;
}

p, ul, ol {
  margin-top: 0;
  margin-bottom: 1rem;
  color: var(--color-text);
}

ul, ol {
  padding-left: 1.5rem;
}

li {
  margin-bottom: 0.4rem;
}

.subtitle {
  font-size: 1.05rem;
  color: var(--color-text-muted);
  margin-bottom: 1.5rem;
}

.meta-date {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  margin-bottom: 1.75rem;
}

/* Callouts / Warnings */
.notice-box {
  background-color: var(--color-surface-elevated);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-primary);
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
  margin: 1.5rem 0;
}

.notice-box.warning {
  background-color: var(--color-callout-bg);
  border-color: var(--color-callout-border);
  border-left: 4px solid var(--color-callout-border);
  color: var(--color-callout-text);
}

.notice-box.warning p,
.notice-box.warning strong {
  color: var(--color-callout-text);
}

.token-badge {
  display: inline-block;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: 0.9em;
  background: #f3f4f6;
  border: 1px dashed #9ca3af;
  padding: 0.1em 0.35em;
  border-radius: var(--radius-sm);
  color: #374151;
}

/* Feature grid on landing page */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1rem;
  margin: 2rem 0;
}

.feature-card {
  background: var(--color-surface-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.25rem;
}

.feature-card h3 {
  margin-top: 0;
  font-size: 1.05rem;
}

.feature-card p {
  font-size: 0.925rem;
  color: var(--color-text-muted);
  margin-bottom: 0;
}

/* Action button */
.btn {
  display: inline-block;
  background-color: var(--color-primary-dark);
  color: #ffffff;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-md);
  font-weight: 600;
  text-decoration: none;
  text-align: center;
  transition: background-color 0.15s ease;
}

.btn:hover {
  background-color: var(--color-primary);
  text-decoration: none;
  color: #ffffff;
}

/* Footer */
.site-footer {
  background-color: var(--color-surface);
  border-top: 1px solid var(--color-border);
  padding: 2rem 1.5rem;
  margin-top: auto;
}

.footer-container {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 1rem;
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

.footer-links {
  display: flex;
  gap: 1.25rem;
  list-style: none;
  margin: 0;
  padding: 0;
  flex-wrap: wrap;
  justify-content: center;
}

.footer-links a {
  color: var(--color-text-muted);
  text-decoration: none;
}

.footer-links a:hover {
  color: var(--color-text);
  text-decoration: underline;
}