/* ============================================================
   ZECH GEORGE — PORTFOLIO
   Palette: deep obsidian bg, electric cyan accent, warm amber
   secondary, cool slate text
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@300;400;500;600;700&family=JetBrains+Mono:wght@300;400;500&display=swap');

/* ── Tokens ─────────────────────────────────────────────── */
:root {
  --bg:           #0a0d12;
  --bg-elevated:  #0f141c;
  --bg-card:      #131920;
  --bg-card-hover:#17202b;
  --border:       #1e2a38;
  --border-light: #253345;

  --cyan:         #00d4ff;
  --cyan-dim:     rgba(0, 212, 255, 0.12);
  --cyan-glow:    rgba(0, 212, 255, 0.25);
  --amber:        #f0a500;
  --amber-dim:    rgba(240, 165, 0, 0.12);

  --text-primary:   #e8edf5;
  --text-secondary: #7a8fa6;
  --text-muted:     #3d5068;

  --font-display: 'Space Grotesk', sans-serif;
  --font-mono:    'JetBrains Mono', monospace;

  --radius:    8px;
  --radius-lg: 16px;
  --transition: 0.2s ease;
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text-primary);
  font-family: var(--font-display);
  font-size: 16px;
  line-height: 1.7;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

/* ── Nav ─────────────────────────────────────────────────── */
.top-nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: rgba(10, 13, 18, 0.85);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
  padding: 0 2rem;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--cyan);
  text-decoration: none;
  letter-spacing: 0.05em;
}
.nav-logo span { color: var(--text-muted); }

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.nav-links a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.82rem;
  font-weight: 500;
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius);
  transition: color var(--transition), background var(--transition);
  letter-spacing: 0.03em;
}
.nav-links a:hover { color: var(--text-primary); background: var(--bg-card); }
.nav-links a.active { color: var(--cyan); }

.nav-divider {
  width: 1px;
  height: 18px;
  background: var(--border);
  margin: 0 0.5rem;
}

.nav-links a.nav-cta {
  color: var(--cyan);
  border: 1px solid rgba(0,212,255,0.3);
  padding: 0.3rem 0.85rem;
}
.nav-links a.nav-cta:hover {
  background: var(--cyan-dim);
  color: var(--cyan);
}

/* ── Layout ──────────────────────────────────────────────── */
.page-wrap {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* ── Hero ────────────────────────────────────────────────── */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 8rem 2rem 5rem;
  max-width: 1100px;
  margin: 0 auto;
  position: relative;
}

.hero-eyebrow {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--cyan);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}
.hero-eyebrow::before {
  content: '';
  display: inline-block;
  width: 32px;
  height: 1px;
  background: var(--cyan);
}

.hero h1 {
  font-size: clamp(3rem, 7vw, 5.5rem);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin-bottom: 1.5rem;
  color: var(--text-primary);
}

.hero h1 .accent {
  color: var(--cyan);
  position: relative;
}

.hero-sub {
  font-size: 1.15rem;
  color: var(--text-secondary);
  max-width: 540px;
  line-height: 1.65;
  margin-bottom: 2.5rem;
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-bottom: 3rem;
}

.tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 0.3rem 0.75rem;
  border-radius: 999px;
  border: 1px solid var(--border-light);
  color: var(--text-secondary);
  letter-spacing: 0.05em;
  transition: border-color var(--transition), color var(--transition);
}
.tag:hover { border-color: var(--cyan); color: var(--cyan); }

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  align-items: center;
}

/* ── Buttons ─────────────────────────────────────────────── */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--cyan);
  color: var(--bg);
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 600;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius);
  text-decoration: none;
  transition: opacity var(--transition), transform var(--transition);
  letter-spacing: 0.02em;
}
.btn-primary:hover { opacity: 0.88; transform: translateY(-1px); }

.btn-ghost {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 500;
  padding: 0.75rem 1.25rem;
  border-radius: var(--radius);
  border: 1px solid var(--border-light);
  text-decoration: none;
  transition: border-color var(--transition), color var(--transition), background var(--transition);
  letter-spacing: 0.02em;
}
.btn-ghost:hover {
  border-color: var(--cyan);
  color: var(--cyan);
  background: var(--cyan-dim);
}

/* ── Section base ────────────────────────────────────────── */
section {
  padding: 5rem 0;
}

.section-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--cyan);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}
.section-label::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border);
  max-width: 60px;
}

.section-title {
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.section-desc {
  color: var(--text-secondary);
  max-width: 560px;
  margin-bottom: 3rem;
  font-size: 1rem;
}

/* ── Divider ─────────────────────────────────────────────── */
.divider {
  height: 1px;
  background: linear-gradient(to right, transparent, var(--border), transparent);
  margin: 0;
}

/* ── Project Card ────────────────────────────────────────── */
.project-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
  text-decoration: none;
  display: block;
  color: inherit;
}
.project-card:hover {
  border-color: var(--border-light);
  transform: translateY(-3px);
  box-shadow: 0 16px 48px rgba(0,0,0,0.4), 0 0 0 1px var(--border-light);
}

.card-vis {
  height: 200px;
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}

/* Animated sparkline in the card visual area */
.card-vis svg {
  opacity: 0.6;
}

.card-body {
  padding: 1.75rem;
}

.card-meta {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--text-muted);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 0.75rem;
}

.card-title {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 0.65rem;
  letter-spacing: -0.01em;
}

.card-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 1.25rem;
}

.card-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: 1.25rem;
}
.chip {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  padding: 0.2rem 0.6rem;
  background: var(--cyan-dim);
  color: var(--cyan);
  border-radius: 4px;
  letter-spacing: 0.04em;
}

.card-link {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--cyan);
  text-decoration: none;
}
.card-link:hover { opacity: 0.75; }

/* ── Skills / Tools grid ─────────────────────────────────── */
.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 1rem;
}
.tool-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-size: 0.85rem;
  font-weight: 500;
  transition: border-color var(--transition), background var(--transition);
}
.tool-item:hover {
  border-color: var(--border-light);
  background: var(--bg-card-hover);
}
.tool-icon {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--cyan);
  min-width: 24px;
}

/* ── About page specifics ────────────────────────────────── */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: start;
}
@media (max-width: 700px) { .about-grid { grid-template-columns: 1fr; } }

.bio-block p {
  color: var(--text-secondary);
  margin-bottom: 1.1rem;
  font-size: 1rem;
  line-height: 1.75;
}
.bio-block p strong { color: var(--text-primary); font-weight: 600; }

.timeline {
  display: flex;
  flex-direction: column;
  gap: 0;
}
.timeline-item {
  display: grid;
  grid-template-columns: 1px 1fr;
  gap: 0 1.5rem;
  position: relative;
}
.timeline-line {
  background: var(--border);
  position: relative;
}
.timeline-line::before {
  content: '';
  position: absolute;
  top: 6px; left: 50%;
  transform: translateX(-50%);
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 8px var(--cyan-glow);
}
.timeline-content {
  padding-bottom: 2.5rem;
}
.timeline-year {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--text-muted);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 0.25rem;
}
.timeline-role {
  font-weight: 600;
  font-size: 0.95rem;
  margin-bottom: 0.2rem;
}
.timeline-org {
  font-size: 0.82rem;
  color: var(--cyan);
  margin-bottom: 0.6rem;
}
.timeline-desc {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ── Project detail page ─────────────────────────────────── */
.detail-header {
  padding: 9rem 0 4rem;
}
.detail-header h1 {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 1rem;
}
.detail-sub {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 640px;
  margin-bottom: 2rem;
}
.detail-chips { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-bottom: 2rem; }

.detail-body {
  max-width: 780px;
  padding-bottom: 6rem;
}
.detail-body h2 {
  font-size: 1.3rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 3rem 0 0.9rem;
  color: var(--text-primary);
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}
.detail-body h2:first-child { border-top: none; margin-top: 0; }
.detail-body p {
  color: var(--text-secondary);
  margin-bottom: 1rem;
  font-size: 0.97rem;
  line-height: 1.75;
}
.detail-body ul {
  list-style: none;
  margin: 0.5rem 0 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}
.detail-body ul li {
  color: var(--text-secondary);
  font-size: 0.95rem;
  padding-left: 1.25rem;
  position: relative;
}
.detail-body ul li::before {
  content: '→';
  position: absolute;
  left: 0;
  color: var(--cyan);
  font-family: var(--font-mono);
}

.detail-stat-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 1rem;
  margin: 2rem 0;
}
.detail-stat {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
}
.detail-stat .stat-val {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 500;
  color: var(--amber);
  display: block;
  margin-bottom: 0.25rem;
}
.detail-stat .stat-label {
  font-size: 0.78rem;
  color: var(--text-muted);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.model-comparison {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin: 2rem 0;
}
.model-comparison table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.85rem;
}
.model-comparison th {
  background: var(--bg-elevated);
  padding: 0.85rem 1.25rem;
  text-align: left;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--text-muted);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border-bottom: 1px solid var(--border);
}
.model-comparison td {
  padding: 0.85rem 1.25rem;
  border-bottom: 1px solid var(--border);
  color: var(--text-secondary);
}
.model-comparison tr:last-child td { border-bottom: none; }
.model-comparison tr:hover td { background: var(--bg-card-hover); }
.mape-best { color: var(--cyan); font-weight: 600; }
.mape-good { color: var(--amber); }

.pipeline-steps {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin: 1.5rem 0;
}
.pipeline-step {
  display: flex;
  gap: 1.25rem;
  align-items: flex-start;
}
.step-num {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-muted);
  min-width: 2rem;
  padding-top: 0.2rem;
}
.step-body {
  border-left: 1px solid var(--border);
  padding: 0 0 1.75rem 1.25rem;
  flex: 1;
}
.pipeline-step:last-child .step-body { border-left: 1px solid transparent; }
.step-title {
  font-weight: 600;
  font-size: 0.9rem;
  margin-bottom: 0.25rem;
}
.step-desc {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ── Social links row ────────────────────────────────────── */
.social-row {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}
.social-link {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  padding: 0.5rem 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: color var(--transition), border-color var(--transition), background var(--transition);
}
.social-link:hover { color: var(--cyan); border-color: var(--cyan); background: var(--cyan-dim); }

/* ── Footer ──────────────────────────────────────────────── */
footer {
  border-top: 1px solid var(--border);
  padding: 2rem;
  text-align: center;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-muted);
  letter-spacing: 0.06em;
}
footer a { color: var(--text-muted); text-decoration: none; }
footer a:hover { color: var(--cyan); }

/* ── Glow bg decoration ──────────────────────────────────── */
.bg-glow {
  position: fixed;
  pointer-events: none;
  z-index: 0;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.04;
}
.bg-glow-1 {
  width: 600px; height: 600px;
  background: var(--cyan);
  top: -200px; left: -100px;
}
.bg-glow-2 {
  width: 400px; height: 400px;
  background: var(--amber);
  bottom: 10%; right: -100px;
}

/* ── Responsive ──────────────────────────────────────────── */
@media (max-width: 768px) {
  .top-nav { padding: 0 1rem; }
  .hero { padding: 7rem 1.25rem 4rem; }
  .page-wrap { padding: 0 1.25rem; }
  .detail-header { padding: 7rem 0 3rem; }
  .detail-stat-row { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 480px) {
  .nav-links a:not(.nav-cta):not([href="index.html"]):not([href="about.html"]):not([href="projects.html"]) {
    display: none;
  }
}