/* Conjecturing8yi - Main stylesheet
   Knowledge Network & Digital Insight
   Mobile-first, semantic, fast loading */

:root {
  --color-bg: #0a0e14;
  --color-surface: #0f1419;
  --color-border: #1a2332;
  --color-text: #e6edf3;
  --color-text-muted: #8b949e;
  --color-accent: #58a6ff;
  --color-accent-muted: #388bfd;
  --color-silver: #c9d1d9;
  --color-dark-blue: #0d1117;
  --font-sans: "DM Sans", system-ui, -apple-system, sans-serif;
  --font-display: "Instrument Sans", var(--font-sans);
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --radius: 0.5rem;
  --radius-lg: 0.75rem;
  --transition: 0.2s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
}

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

img[loading="lazy"] {
  content-visibility: auto;
}

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

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

/* Skip link */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-md);
  z-index: 100;
  padding: var(--space-sm) var(--space-md);
  background: var(--color-accent);
  color: var(--color-bg);
  border-radius: var(--radius);
  font-weight: 600;
  transition: top var(--transition);
}

.skip-link:focus {
  top: var(--space-md);
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(10, 14, 20, 0.9);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-lg);
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--space-md) var(--space-lg);
}

.site-logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.25rem;
  color: var(--color-text);
}

.site-logo img {
  width: 36px;
  height: 36px;
  object-fit: contain;
}

/* Nav */
.nav-main {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-main a {
  display: block;
  padding: var(--space-sm) var(--space-md);
  color: var(--color-text-muted);
  border-radius: var(--radius);
  font-size: 0.9375rem;
}

.nav-main a:hover,
.nav-main a[aria-current="page"] {
  color: var(--color-text);
  background: var(--color-surface);
}

/* Hero */
.hero {
  position: relative;
  min-height: 60vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: var(--space-3xl) var(--space-lg);
  overflow: hidden;
}

.hero__media {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.35;
}

.hero__media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, var(--color-bg) 0%, transparent 40%, var(--color-bg) 100%);
}

.hero__content {
  position: relative;
  z-index: 1;
  max-width: 720px;
  margin: 0 auto;
  text-align: center;
}

.hero__title {
  font-family: var(--font-display);
  font-size: clamp(1.75rem, 5vw, 2.75rem);
  font-weight: 600;
  line-height: 1.25;
  margin: 0 0 var(--space-md);
  color: var(--color-text);
}

.hero__subtext {
  font-size: 1.0625rem;
  color: var(--color-text-muted);
  margin: 0 0 var(--space-xl);
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}

.hero__cta {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-md) var(--space-xl);
  background: var(--color-accent);
  color: var(--color-bg);
  font-weight: 600;
  border-radius: var(--radius-lg);
  transition: background var(--transition), transform var(--transition);
}

.hero__cta:hover {
  background: var(--color-accent-muted);
  color: var(--color-bg);
  transform: translateY(-2px);
}

/* Breadcrumb */
.breadcrumb {
  padding: var(--space-md) var(--space-lg);
  max-width: 1200px;
  margin: 0 auto;
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
  align-items: center;
  list-style: none;
  margin: 0;
  padding: 0;
}

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

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

.breadcrumb span[aria-hidden="true"] {
  margin: 0 var(--space-xs);
  color: var(--color-border);
}

/* Main content */
.main-content {
  max-width: 800px;
  margin: 0 auto;
  padding: var(--space-2xl) var(--space-lg);
}

.page-title {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 4vw, 2rem);
  font-weight: 600;
  margin: 0 0 var(--space-lg);
  color: var(--color-text);
}

.section-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin: var(--space-xl) 0 var(--space-md);
  color: var(--color-silver);
}

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

.prose p {
  margin: 0 0 var(--space-md);
}

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

.prose a {
  text-decoration: underline;
  text-underline-offset: 2px;
}

/* Subfolder banner */
.page-banner {
  position: relative;
  height: 280px;
  overflow: hidden;
}

.page-banner img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.page-banner::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 0%, var(--color-bg) 85%);
}

/* Card grid (insight, research) */
.card-grid {
  display: grid;
  gap: var(--space-lg);
  margin-top: var(--space-xl);
}

@media (min-width: 640px) {
  .card-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  transition: border-color var(--transition);
}

.card:hover {
  border-color: var(--color-accent-muted);
}

.card h3 {
  font-size: 1.0625rem;
  font-weight: 600;
  margin: 0 0 var(--space-sm);
  color: var(--color-text);
}

.card p {
  font-size: 0.9375rem;
  color: var(--color-text-muted);
  margin: 0;
}

.card a {
  display: inline-block;
  margin-top: var(--space-sm);
  font-size: 0.875rem;
  font-weight: 500;
}

/* Footer */
.site-footer {
  margin-top: var(--space-3xl);
  padding: var(--space-xl) var(--space-lg);
  border-top: 1px solid var(--color-border);
  background: var(--color-surface);
}

.site-footer__inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: var(--space-lg);
  align-items: center;
}

.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
}

.site-footer a {
  color: var(--color-text-muted);
  font-size: 0.9375rem;
}

.site-footer a:hover {
  color: var(--color-text);
}

.site-footer__copy {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  margin: 0;
}

/* Utility */
.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;
}

/* Print */
@media print {
  .site-header { position: relative; }
  .skip-link { display: none; }
  .hero__media { display: none; }
  .hero__media::after { display: none; }
}