:root {
  --primary: #1a1a2e;
  --accent: #16213e;
  --highlight: #0f3460;
  --link: #2e86ab;
  --text: #333;
  --text-light: #666;
  --bg: #fff;
  --alt-bg: #f7f8fa;
  --border: #e8e8e8;
  --radius: 6px;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}

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

/* Nav */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: var(--primary);
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}
.nav-inner {
  max-width: 960px; margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 20px;
}
.nav-brand { color: #fff; font-weight: 700; font-size: 1.1rem; }
.nav-brand:hover { text-decoration: none; }
.nav-links a { color: rgba(255,255,255,0.8); margin-left: 20px; font-size: 0.9rem; }
.nav-links a:hover { color: #fff; text-decoration: none; }

/* Hero */
.hero {
  padding: 140px 20px 80px;
  text-align: center;
  background: linear-gradient(135deg, var(--primary), var(--highlight));
  color: #fff;
}
.hero h1 { font-size: 2.8rem; font-weight: 700; margin-bottom: 8px; }
.hero-title { font-size: 1.3rem; opacity: 0.9; margin-bottom: 4px; }
.hero-tagline { font-size: 1rem; opacity: 0.7; max-width: 600px; margin: 0 auto 20px; }
.hero-links a {
  display: inline-block; margin: 0 8px;
  padding: 8px 20px; border: 1px solid rgba(255,255,255,0.4);
  border-radius: var(--radius); color: #fff; font-size: 0.9rem;
}
.hero-links a:hover { background: rgba(255,255,255,0.1); text-decoration: none; }

/* Sections */
.section { max-width: 800px; margin: 0 auto; padding: 60px 20px; }
.section h2 {
  font-size: 1.5rem; color: var(--primary); margin-bottom: 24px;
  padding-bottom: 8px; border-bottom: 2px solid var(--link);
}
.alt-bg { background: var(--alt-bg); max-width: 100%; }
.alt-bg > h2, .alt-bg > .skills-grid, .alt-bg > .projects-grid, .alt-bg > p {
  max-width: 800px; margin-left: auto; margin-right: auto;
}

/* Skills */
.skills-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 20px; }
.skill-group { background: var(--bg); padding: 18px; border-radius: var(--radius); border: 1px solid var(--border); }
.skill-group h3 { font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.5px; color: var(--link); margin-bottom: 10px; }
.skill-items { display: flex; flex-wrap: wrap; gap: 6px; }
.skill-tag { background: var(--alt-bg); border: 1px solid var(--border); padding: 4px 10px; border-radius: 3px; font-size: 0.85rem; }

/* Experience */
.job { margin-bottom: 28px; }
.job-header { display: flex; justify-content: space-between; align-items: flex-start; flex-wrap: wrap; margin-bottom: 8px; }
.job h3 { font-size: 1.05rem; color: var(--text); }
.company { color: var(--link); font-size: 0.9rem; }
.period { font-size: 0.85rem; color: var(--text-light); white-space: nowrap; }
.job ul { padding-left: 18px; }
.job li { font-size: 0.9rem; margin-bottom: 4px; color: var(--text); }

/* Projects */
.projects-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 20px; }
.project-card {
  background: var(--bg); padding: 22px; border-radius: var(--radius);
  border: 1px solid var(--border); transition: box-shadow 0.2s;
}
.project-card:hover { box-shadow: 0 4px 12px rgba(0,0,0,0.08); }
.project-card h3 { font-size: 1rem; color: var(--primary); margin-bottom: 8px; display: flex; align-items: center; gap: 6px; }
.project-link { font-size: 0.85rem; color: var(--link); }
.project-card p { font-size: 0.9rem; color: var(--text-light); margin-bottom: 12px; line-height: 1.5; }
.tags { display: flex; flex-wrap: wrap; gap: 6px; }
.tag { background: var(--highlight); color: #fff; font-size: 0.75rem; padding: 3px 9px; border-radius: 3px; }

/* Education */
.edu-item { margin-bottom: 10px; font-size: 0.95rem; }
.year { color: var(--text-light); font-size: 0.85rem; }
.note { color: var(--text-light); font-size: 0.85rem; font-style: italic; }

/* Contact */
.contact-section { text-align: center; }
.contact-section p { font-size: 1rem; }
.contact-section a { margin: 0 6px; }

/* Footer */
footer { text-align: center; padding: 20px; font-size: 0.8rem; color: var(--text-light); border-top: 1px solid var(--border); }

/* Responsive */
@media (max-width: 600px) {
  .hero h1 { font-size: 2rem; }
  .hero-title { font-size: 1.1rem; }
  .nav-links { display: none; }
  .section { padding: 40px 16px; }
  .job-header { flex-direction: column; }
}