:root {
  --color-bg: #ffffff;
  --color-surface: #f9fafb;
  --color-border: #e5e7eb;
  --color-text: #111827;
  --color-text-secondary: #6b7280;
  --color-accent: #2563eb;
  --color-accent-light: #eff6ff;
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --radius: 8px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 20px rgba(0,0,0,0.1);
}

* { box-sizing: border-box; }

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  margin: 0;
  -webkit-font-smoothing: antialiased;
}

/* Navbar */
.navbar {
  border-bottom: 1px solid var(--color-border);
  background: rgba(255,255,255,0.95) !important;
  backdrop-filter: blur(8px);
  padding: 1rem 0;
}
.navbar-brand {
  font-weight: 700;
  font-size: 1rem;
  color: var(--color-text) !important;
  letter-spacing: -0.02em;
}
.nav-link {
  color: var(--color-text-secondary) !important;
  font-size: 0.875rem;
  font-weight: 500;
  padding: 0.35rem 0.75rem !important;
  border-radius: var(--radius);
  transition: color 0.15s, background 0.15s;
}
.nav-link:hover {
  color: var(--color-accent) !important;
  background: var(--color-accent-light);
}
.nav-link.active {
  color: var(--color-accent) !important;
  font-weight: 600;
}

/* Hero */
.hero {
  padding: 7rem 0 4.5rem;
  border-bottom: 1px solid var(--color-border);
}
.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background: var(--color-accent-light);
  color: var(--color-accent);
  font-size: 0.72rem;
  font-weight: 600;
  padding: 0.3rem 0.85rem;
  border-radius: 999px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 1.5rem;
}
.hero-tag::before {
  content: '';
  display: inline-block;
  width: 6px;
  height: 6px;
  background: var(--color-accent);
  border-radius: 50%;
}
.hero h1 {
  font-size: clamp(2.75rem, 5vw, 4rem);
  font-weight: 700;
  letter-spacing: -0.035em;
  line-height: 1.08;
  margin-bottom: 0.5rem;
}
.hero .subtitle {
  font-size: 1.15rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  margin-bottom: 1.25rem;
}
.hero .lead {
  font-size: 0.975rem;
  color: var(--color-text-secondary);
  max-width: 480px;
  line-height: 1.8;
  margin-bottom: 2rem;
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 2.5rem;
}

/* Buttons */
.btn-primary {
  background: var(--color-accent) !important;
  border-color: var(--color-accent) !important;
  border-radius: var(--radius) !important;
  font-weight: 600 !important;
  font-size: 0.875rem !important;
  padding: 0.65rem 1.5rem !important;
  color: #fff !important;
  transition: opacity 0.15s !important;
  text-decoration: none;
  display: inline-block;
}
.btn-primary:hover { opacity: 0.88 !important; }

.btn-outline {
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.875rem;
  padding: 0.65rem 1.5rem;
  color: var(--color-text);
  background: transparent;
  cursor: pointer;
  text-decoration: none;
  display: inline-block;
  transition: border-color 0.15s, color 0.15s;
}
.btn-outline:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* Metric chips */
.metric-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}
.metric-chip {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 0.45rem 0.9rem;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--color-text-secondary);
}
.metric-chip strong {
  color: var(--color-text);
}

/* Sections */
.section {
  padding: 4rem 0;
  border-bottom: 1px solid var(--color-border);
}
.section-label {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-text-secondary);
  margin-bottom: 0.4rem;
}
.section h2 {
  font-size: 1.65rem;
  font-weight: 700;
  letter-spacing: -0.025em;
  margin-bottom: 0.5rem;
}
.section-intro {
  font-size: 0.925rem;
  color: var(--color-text-secondary);
  max-width: 520px;
  line-height: 1.75;
  margin-bottom: 2.5rem;
}

/* Stat cards */
.stat-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.5rem 1.25rem;
}
.stat-number {
  font-size: 2.1rem;
  font-weight: 700;
  letter-spacing: -0.04em;
  color: var(--color-accent);
  line-height: 1;
  margin-bottom: 0.4rem;
}
.stat-label {
  font-size: 0.78rem;
  color: var(--color-text-secondary);
  line-height: 1.55;
}

/* Timeline */
.timeline {
  position: relative;
  padding-left: 1.75rem;
}
.timeline::before {
  content: '';
  position: absolute;
  left: 4px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--color-border);
}
.timeline-item {
  position: relative;
  padding-bottom: 2.5rem;
}
.timeline-item:last-child { padding-bottom: 0; }
.timeline-dot {
  position: absolute;
  left: -1.75rem;
  top: 5px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--color-accent);
  border: 2px solid var(--color-bg);
  box-shadow: 0 0 0 1.5px var(--color-accent);
}
.timeline-company {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 0.2rem;
}
.timeline-role {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 0.15rem;
  letter-spacing: -0.01em;
}
.timeline-dates {
  font-size: 0.775rem;
  color: var(--color-text-secondary);
  margin-bottom: 0.875rem;
}
.timeline-item ul {
  padding-left: 1.1rem;
  margin: 0;
}
.timeline-item li {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  margin-bottom: 0.45rem;
  line-height: 1.65;
}

/* Project cards */
.project-card {
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.75rem;
  height: 100%;
  display: flex;
  flex-direction: column;
  transition: box-shadow 0.2s, transform 0.2s;
  background: var(--color-bg);
}
.project-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}
.project-tag {
  display: inline-block;
  font-size: 0.67rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-accent);
  background: var(--color-accent-light);
  padding: 0.2rem 0.6rem;
  border-radius: 999px;
  margin-bottom: 0.875rem;
  width: fit-content;
}
.project-tag.tag-code {
  color: #059669;
  background: #ecfdf5;
}
.project-tag.tag-wip {
  color: #d97706;
  background: #fffbeb;
}
.project-card h4 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  letter-spacing: -0.01em;
}
.project-card p {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  flex-grow: 1;
  line-height: 1.7;
  margin: 0;
}
.card-footer-area {
  margin-top: 1.25rem;
  padding-top: 1rem;
  border-top: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  gap: 0.4rem;
  flex-wrap: wrap;
}
.tech-pill {
  font-size: 0.7rem;
  font-weight: 500;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  padding: 0.18rem 0.55rem;
  color: var(--color-text-secondary);
}

/* Skills */
.skill-tag {
  display: inline-block;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 0.4rem 0.875rem;
  font-size: 0.8rem;
  font-weight: 500;
  margin: 0.2rem;
  color: var(--color-text);
}

/* Cert items */
.cert-item {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 0.875rem 0;
  border-bottom: 1px solid var(--color-border);
}
.cert-item:last-child { border-bottom: none; }
.cert-icon {
  width: 34px;
  height: 34px;
  border-radius: var(--radius);
  background: var(--color-accent-light);
  color: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  flex-shrink: 0;
  font-weight: 700;
}
.cert-name {
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 0.1rem;
}
.cert-abbr {
  font-size: 0.75rem;
  color: var(--color-text-secondary);
}

/* About photo */
.about-photo {
  width: 100%;
  max-width: 260px;
  border-radius: var(--radius);
  border: 1px solid var(--color-border);
  display: block;
}

/* Contact box */
.contact-box {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 2.5rem 2rem;
  text-align: center;
}
.contact-box h3 {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 0.5rem;
}
.contact-box p {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  margin-bottom: 1.5rem;
  line-height: 1.7;
}

/* Footer */
footer {
  padding: 2rem 0;
  text-align: center;
  font-size: 0.775rem;
  color: var(--color-text-secondary);
}
footer a {
  color: var(--color-text-secondary);
  text-decoration: none;
}
footer a:hover { color: var(--color-accent); }

/* Responsive */
@media (max-width: 768px) {
  .hero { padding: 5.5rem 0 3rem; }
  .section { padding: 3rem 0; }
  .hero h1 { font-size: 2.4rem; }
  .about-photo { max-width: 200px; margin-bottom: 2rem; }
}