/* ============================================================
   avonsi.com — Design System & Stylesheet
   Minimalist, editorial, high-signal enterprise architecture site
   ============================================================ */

:root {
  --bg: #fafaf8;
  --bg-card: #ffffff;
  --bg-subtle: #f2f2ee;
  --text-main: #111111;
  --text-muted: #525252;
  --text-dim: #616161;
  --border: #e2e2dc;
  --border-focus: #111111;
  
  --accent-blue: #23527c;
  --accent-green: #2d6a4f;
  --accent-green-bg: #eaf3ed;
  --tag-bg: #eaeae4;
  --tag-text: #333333;

  --font-sans: "DM Sans", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-serif: "Lora", "Charter", "Bitstream Charter", "Sitka Text", Cambria, Georgia, serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SF Mono", "Cascadia Code", "Segoe UI Mono", Menlo, Consolas, monospace;

  --container-max: 1080px;
  --radius: 8px;
  --transition: 0.2s ease;
}

html.dark body {
  --bg: #141414;
  --bg-card: #1c1c1c;
  --bg-subtle: #242424;
  --text-main: #ededed;
  --text-muted: #a6a6a6;
  --text-dim: #808080;
  --border: #2e2e2e;
  --border-focus: #ededed;
  
  --accent-blue: #6495ed;
  --accent-green: #52b788;
  --accent-green-bg: #192b21;
  --tag-bg: #2b2b2b;
  --tag-text: #d0d0d0;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  color-scheme: light dark;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg);
  color: var(--text-main);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition), opacity var(--transition);
}

a:hover {
  color: var(--border-focus);
}

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

/* ── Header ── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(250, 250, 248, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
  transition: background var(--transition);
}

html.dark .site-header {
  background: rgba(20, 20, 20, 0.92);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 600;
  font-size: 1.15rem;
  letter-spacing: -0.01em;
  text-decoration: none;
}

.brand-logo {
  height: 38px;
  width: auto;
  border-radius: 4px;
  display: block;
}

.brand-logo-rect {
  height: 42px;
  width: auto;
  max-width: 155px;
  aspect-ratio: 132 / 44;
  object-fit: contain;
  border-radius: 4px;
  display: block;
  transition: opacity var(--transition);
}

.brand:hover .brand-logo-rect {
  opacity: 0.9;
}

html.dark .brand-logo-rect {
  background: #ffffff;
  padding: 3px 6px;
  border-radius: 6px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.35);
}

.nav {
  display: flex;
  align-items: center;
  gap: 24px;
  font-size: 0.92rem;
  font-weight: 500;
}

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

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

.theme-toggle {
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  color: var(--text-main);
  padding: 6px 12px;
  border-radius: 6px;
  cursor: pointer;
  font-family: var(--font-sans);
  font-size: 0.85rem;
  transition: background var(--transition), border-color var(--transition);
}

.theme-toggle:hover {
  border-color: var(--text-muted);
}

/* ── Hero Section ── */
.hero {
  padding: 80px 0 60px;
  border-bottom: 1px solid var(--border);
}

.hero-eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent-green);
  background: var(--accent-green-bg);
  padding: 4px 10px;
  border-radius: 4px;
  margin-bottom: 20px;
}

.hero-title {
  font-family: var(--font-serif);
  font-size: 2.75rem;
  line-height: 1.25;
  font-weight: 500;
  letter-spacing: -0.02em;
  margin-bottom: 24px;
  max-width: 900px;
}

.hero-lead {
  font-size: 1.15rem;
  color: var(--text-muted);
  max-width: 820px;
  line-height: 1.7;
  margin-bottom: 32px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  align-items: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  min-height: 44px;
  border-radius: 6px;
  font-size: 0.95rem;
  font-weight: 500;
  transition: all var(--transition);
}

.btn-primary {
  background: var(--text-main);
  color: var(--bg);
}

.btn-primary:hover {
  opacity: 0.9;
  color: var(--bg);
}

.btn-secondary {
  background: transparent;
  color: var(--text-main);
  border: 1px solid var(--border);
}

.btn-secondary:hover {
  background: var(--bg-subtle);
  border-color: var(--text-muted);
}

/* ── Section General ── */
.section {
  padding: 72px 0;
  border-bottom: 1px solid var(--border);
}

.section-header {
  margin-bottom: 40px;
}

.section-label {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dim);
  margin-bottom: 8px;
}

.section-title {
  font-family: var(--font-serif);
  font-size: 1.9rem;
  font-weight: 500;
  letter-spacing: -0.01em;
  color: var(--text-main);
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 760px;
  margin-top: 8px;
}

/* ── Practice Grid (4 Columns / Cards) ── */
.grid-2x2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.practice-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  display: flex;
  flex-direction: column;
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
}

.practice-card:hover {
  border-color: var(--border-focus);
  box-shadow: 0 4px 16px rgba(0,0,0,0.04);
}

.card-num {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-dim);
  margin-bottom: 16px;
}

.card-title {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 500;
  margin-bottom: 12px;
  line-height: 1.35;
}

.card-desc {
  color: var(--text-muted);
  font-size: 0.96rem;
  margin-bottom: 20px;
  flex-grow: 1;
}

.card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}

.tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  background: var(--tag-bg);
  color: var(--tag-text);
  padding: 4px 8px;
  border-radius: 4px;
}

/* ── Systems & Track Record ── */
.systems-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.system-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
}

.system-role {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  color: var(--text-dim);
  margin-bottom: 6px;
}

.system-title {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  font-weight: 500;
  margin-bottom: 12px;
}

.system-detail {
  font-size: 0.94rem;
  color: var(--text-muted);
  margin-bottom: 14px;
}

.system-metrics {
  font-size: 0.88rem;
  color: var(--text-main);
  background: var(--bg-subtle);
  padding: 10px 14px;
  border-radius: 6px;
  font-family: var(--font-mono);
}

/* ── Guides & Field Notes ── */
.curriculum-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 24px;
}

.featured-guide-card {
  grid-column: 1 / -1;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent-green);
  border-radius: var(--radius);
  padding: 32px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.featured-guide-card:hover {
  border-color: var(--border-focus);
  box-shadow: 0 4px 16px rgba(0,0,0,0.05);
}

.guides-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 16px;
}

.guide-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  display: block;
  transition: border-color var(--transition);
}

.guide-item:hover {
  border-color: var(--border-focus);
}

.guide-badge {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-dim);
  text-transform: uppercase;
  margin-bottom: 4px;
}

.guide-title {
  font-size: 1.05rem;
  font-weight: 500;
  margin-bottom: 6px;
}

.guide-snippet {
  font-size: 0.88rem;
  color: var(--text-muted);
}

/* ── About Profile ── */
.about-wrap {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 40px;
  align-items: start;
}

.about-avatar-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  text-align: center;
}

.about-avatar-logo {
  width: 96px;
  height: 96px;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  border-radius: 50%;
  margin: 0 auto 16px;
  display: block;
  border: 1px solid var(--border);
}

.about-name {
  font-family: var(--font-serif);
  font-size: 1.3rem;
  font-weight: 500;
  margin-bottom: 4px;
}

.about-role {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 16px;
}

.about-meta-list {
  text-align: left;
  border-top: 1px solid var(--border);
  padding-top: 16px;
  font-size: 0.86rem;
  color: var(--text-muted);
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.about-content p {
  margin-bottom: 16px;
  font-size: 1.02rem;
  color: var(--text-muted);
}

.about-bullet-list {
  margin: 0 0 20px 20px;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.about-bullet-list li {
  font-size: 0.98rem;
  line-height: 1.6;
  color: var(--text-muted);
}

.about-bullet-list li strong {
  color: var(--text-main);
  font-weight: 600;
}

.about-content strong {
  color: var(--text-main);
  font-weight: 600;
}

/* ── Contact Section ── */
.contact-box {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 48px;
  text-align: center;
}

.contact-title {
  font-family: var(--font-serif);
  font-size: 2rem;
  font-weight: 500;
  margin-bottom: 12px;
}

.contact-subtitle {
  color: var(--text-muted);
  max-width: 600px;
  margin: 0 auto 28px;
  font-size: 1.05rem;
}

.contact-methods {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 20px;
}

.contact-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  padding: 10px 20px;
  min-height: 44px;
  border-radius: 6px;
  font-size: 0.95rem;
  font-weight: 500;
}

.contact-badge:hover {
  border-color: var(--border-focus);
}

/* ── Footer ── */
.site-footer {
  padding: 40px 0;
  text-align: center;
  font-size: 0.88rem;
  color: var(--text-dim);
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin-bottom: 12px;
}

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

/* ── Featured Guide Helpers ── */
.featured-eyebrow {
  margin-bottom: 8px;
}
.featured-title {
  margin-bottom: 6px;
}
.featured-desc {
  margin-bottom: 0;
}
.btn-nowrap {
  white-space: nowrap;
}
.curriculum-label {
  margin-bottom: 16px;
}

/* ── 404 Page ── */
.not-found-wrap {
  min-height: 70vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 40px 20px;
}
.not-found-num {
  font-size: 5rem;
  font-weight: 700;
  color: var(--accent-blue);
  line-height: 1;
  margin-bottom: 16px;
}
.not-found-desc {
  font-size: 1.2rem;
  color: var(--text-muted);
  max-width: 480px;
  margin-bottom: 32px;
}

/* ── Responsive ── */
@media (max-width: 860px) {
  .hero-title { font-size: 2.1rem; }
  .grid-2x2, .systems-grid { grid-template-columns: 1fr; }
  .about-wrap { grid-template-columns: 1fr; }
  .nav { gap: 16px; }
  .nav a:not(:last-child) { display: none; } /* keep primary on mobile */
  .featured-guide-card { flex-direction: column; align-items: flex-start; }
}