/* ==========================================================
   onyekaogbonna.com — portfolio stylesheet
   Dark, minimal, fast. No frameworks, no build step.
   ========================================================== */

:root {
  --bg: #0a0e14;
  --surface: #101722;
  --surface-2: #16202e;
  --border: #223042;
  --text: #e6edf3;
  --muted: #94a3b3;
  --accent: #2dd4bf;
  --accent-dim: rgba(45, 212, 191, 0.12);
  --amber: #fbbf24;
  --font-body: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-head: "Space Grotesk", var(--font-body);
  --font-mono: "JetBrains Mono", ui-monospace, "Cascadia Code", Consolas, monospace;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 1.0625rem;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 1060px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

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

h1, h2, h3 { font-family: var(--font-head); line-height: 1.2; letter-spacing: -0.01em; }

::selection { background: var(--accent); color: #04241f; }

/* ---------- nav ---------- */

.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(10, 14, 20, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav-logo {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1rem;
  color: var(--text);
}
.nav-logo:hover { text-decoration: none; color: var(--accent); }
.nav-logo span { color: var(--accent); }

.nav-links { display: flex; gap: 1.75rem; list-style: none; }
.nav-links a {
  color: var(--muted);
  font-size: 0.9375rem;
  font-weight: 500;
}
.nav-links a:hover { color: var(--text); text-decoration: none; }

/* ---------- hero ---------- */

.hero { padding: 6.5rem 0 5rem; }

.hero-kicker {
  font-family: var(--font-mono);
  color: var(--accent);
  font-size: 0.9375rem;
  margin-bottom: 1.25rem;
}

.hero h1 {
  font-size: clamp(2.4rem, 6vw, 3.9rem);
  font-weight: 700;
  margin-bottom: 1rem;
}

.hero .tagline {
  font-size: clamp(1.15rem, 2.5vw, 1.45rem);
  color: var(--muted);
  max-width: 44ch;
  margin-bottom: 1.5rem;
}
.hero .tagline strong { color: var(--text); font-weight: 600; }

.hero-meta {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--muted);
  margin-bottom: 2.25rem;
}

.btn-row { display: flex; flex-wrap: wrap; gap: 0.875rem; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.7rem 1.4rem;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.9375rem;
  border: 1px solid var(--border);
  color: var(--text);
  transition: border-color 0.15s, background 0.15s, transform 0.15s;
}
.btn:hover { text-decoration: none; border-color: var(--accent); transform: translateY(-1px); }

.btn-primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #04241f;
}
.btn-primary:hover { background: #5eead4; }

/* ---------- sections ---------- */

section { padding: 4.5rem 0; }

.section-head { margin-bottom: 2.5rem; }

.section-head .index {
  font-family: var(--font-mono);
  color: var(--accent);
  font-size: 0.9375rem;
}

.section-head h2 { font-size: 1.9rem; margin-top: 0.35rem; }

.section-head p.sub { color: var(--muted); margin-top: 0.6rem; max-width: 62ch; }

/* ---------- about ---------- */

.about-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr;
  gap: 3rem;
  align-items: start;
}

.about-text p + p { margin-top: 1.1rem; }
.about-text .highlight { color: var(--text); font-weight: 600; }

.fact-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem;
}
.fact-card h3 {
  font-size: 0.8125rem;
  font-family: var(--font-mono);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
  margin-bottom: 1rem;
}
.fact-card ul { list-style: none; }
.fact-card li {
  padding: 0.55rem 0;
  border-bottom: 1px solid var(--border);
  font-size: 0.9375rem;
  display: flex;
  gap: 0.6rem;
  align-items: baseline;
}
.fact-card li:last-child { border-bottom: none; }
.fact-card li::before { content: "▸"; color: var(--accent); flex-shrink: 0; }

/* ---------- projects ---------- */

.project-grid { display: grid; gap: 1.5rem; }

.project-card {
  display: block;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 2rem;
  color: var(--text);
  transition: border-color 0.15s, transform 0.15s;
}
.project-card:hover {
  text-decoration: none;
  border-color: var(--accent);
  transform: translateY(-2px);
}

.project-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  margin-bottom: 0.9rem;
  flex-wrap: wrap;
}

.project-card h3 { font-size: 1.3rem; }

.status {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: 0.25rem 0.7rem;
  border-radius: 999px;
  white-space: nowrap;
}
.status.in-progress { background: rgba(251, 191, 36, 0.12); color: var(--amber); border: 1px solid rgba(251, 191, 36, 0.35); }
.status.planned { background: var(--surface-2); color: var(--muted); border: 1px solid var(--border); }
.status.live { background: var(--accent-dim); color: var(--accent); border: 1px solid rgba(45, 212, 191, 0.4); }

.project-card p.desc { color: var(--muted); margin-bottom: 1.1rem; max-width: 70ch; }

.chips { display: flex; flex-wrap: wrap; gap: 0.45rem; }
.chip {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--muted);
  background: var(--surface-2);
  border: 1px solid var(--border);
  padding: 0.2rem 0.6rem;
  border-radius: 6px;
}

.project-card .cta {
  display: inline-block;
  margin-top: 1.2rem;
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--accent);
}

/* ---------- skills ---------- */

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 1.25rem;
}

.skill-group {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.4rem;
}
.skill-group h3 {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  margin-bottom: 0.9rem;
}
.skill-group ul { list-style: none; }
.skill-group li { color: var(--muted); font-size: 0.9375rem; padding: 0.22rem 0; }

/* ---------- writing ---------- */

.writing-empty {
  background: var(--surface);
  border: 1px dashed var(--border);
  border-radius: 12px;
  padding: 2rem;
  color: var(--muted);
  max-width: 70ch;
}
.writing-empty code {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--accent);
}

/* ---------- contact / footer ---------- */

.contact { text-align: center; padding: 5.5rem 0; }
.contact h2 { font-size: 2rem; margin-bottom: 0.9rem; }
.contact p { color: var(--muted); max-width: 52ch; margin: 0 auto 2rem; }

footer {
  border-top: 1px solid var(--border);
  padding: 2rem 0;
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  color: var(--muted);
  font-size: 0.875rem;
}
.footer-links { display: flex; gap: 1.5rem; }
.footer-links a { color: var(--muted); }
.footer-links a:hover { color: var(--accent); }

/* ---------- case study pages ---------- */

.case { padding: 4rem 0; max-width: 800px; margin: 0 auto; }

.back-link {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  display: inline-block;
  margin-bottom: 2.25rem;
  color: var(--muted);
}
.back-link:hover { color: var(--accent); text-decoration: none; }

.case h1 { font-size: clamp(1.9rem, 4.5vw, 2.6rem); margin: 0.75rem 0 1rem; }

.case .lede { color: var(--muted); font-size: 1.15rem; margin-bottom: 2rem; }

.case h2 {
  font-size: 1.35rem;
  margin: 2.75rem 0 1rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}

.case p + p { margin-top: 1rem; }
.case ul { margin: 1rem 0 1rem 1.25rem; }
.case li { margin: 0.4rem 0; }
.case li::marker { color: var(--accent); }

.case-links { display: flex; gap: 0.875rem; flex-wrap: wrap; margin: 1.75rem 0; }

/* architecture flow diagram */
.arch {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin: 1.5rem 0;
}
.arch-step {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.9rem 1.2rem;
}
.arch-step .label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  display: block;
  margin-bottom: 0.15rem;
}
.arch-step .detail { color: var(--muted); font-size: 0.9375rem; }
.arch-arrow {
  text-align: center;
  color: var(--accent);
  font-size: 1.1rem;
  line-height: 1.6;
}

/* ---------- responsive ---------- */

@media (max-width: 760px) {
  .nav-links { gap: 1.1rem; }
  .nav-links .hide-mobile { display: none; }
  .hero { padding: 4.5rem 0 3.5rem; }
  .about-grid { grid-template-columns: 1fr; gap: 2rem; }
  section { padding: 3.25rem 0; }
}

@media (max-width: 480px) {
  .nav-logo { font-size: 0.8125rem; }
  .nav-links { gap: 0.85rem; }
  .nav-links a { font-size: 0.8125rem; }
}