/* ────────────────────────────────────────────────────────────
   Design tokens
──────────────────────────────────────────────────────────── */
:root {
  --bg:          #0a0f1e;
  --bg-alt:      #0d1426;
  --bg-card:     #111827;
  --border:      #1e2d45;
  --accent:      #64ffda;
  --accent-dim:  rgba(100, 255, 218, 0.12);
  --text-1:      #ccd6f6;
  --text-2:      #8892b0;
  --text-3:      #4a5568;
  --white:       #e6f1ff;
  --font-sans:   'Inter', system-ui, sans-serif;
  --font-mono:   'Fira Code', monospace;
  --radius:      8px;
  --radius-lg:   14px;
  --transition:  0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --nav-h:       70px;
  --max-w:       900px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-h);
}

body {
  background: var(--bg);
  color: var(--text-1);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
ul { list-style: none; }
img { display: block; max-width: 100%; }

/* ────────────────────────────────────────────────────────────
   Utility
──────────────────────────────────────────────────────────── */
.container {
  width: 100%;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 2rem;
}

.text-accent { color: var(--accent); }

/* ────────────────────────────────────────────────────────────
   Navigation
──────────────────────────────────────────────────────────── */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--nav-h);
  background: rgba(10, 15, 30, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition), background var(--transition);
}

.nav.scrolled {
  border-bottom-color: var(--border);
  background: rgba(10, 15, 30, 0.97);
}

.nav-container {
  max-width: 1100px;
  margin: 0 auto;
  height: 100%;
  padding: 0 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-family: var(--font-mono);
  font-size: 1.2rem;
  font-weight: 500;
  color: var(--accent);
  letter-spacing: 0.05em;
  transition: opacity var(--transition);
}
.nav-logo:hover { opacity: 0.8; }

.nav-links {
  display: flex;
  align-items: center;
  gap: 2.5rem;
}

.nav-link {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--text-2);
  transition: color var(--transition);
  counter-increment: nav-counter;
}
.nav-link:hover { color: var(--accent); }

.nav-cta {
  color: var(--accent) !important;
  border: 1px solid var(--accent);
  padding: 0.45rem 1rem;
  border-radius: var(--radius);
  transition: background var(--transition), color var(--transition) !important;
}
.nav-cta:hover {
  background: var(--accent-dim);
}

/* Hamburger */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--accent);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

/* ────────────────────────────────────────────────────────────
   Hero
──────────────────────────────────────────────────────────── */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: calc(var(--nav-h) + 2rem) 2rem 4rem;
  max-width: var(--max-w);
  margin: 0 auto;
}

.hero-greeting {
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--accent);
  margin-bottom: 1.25rem;
  animation: fadeUp 0.6s ease both;
  animation-delay: 0.1s;
}

.hero-name {
  font-size: clamp(2.8rem, 7vw, 5.5rem);
  font-weight: 700;
  color: var(--white);
  line-height: 1.05;
  letter-spacing: -0.02em;
  margin-bottom: 0.5rem;
  animation: fadeUp 0.6s ease both;
  animation-delay: 0.2s;
}

.hero-title {
  font-size: clamp(1.1rem, 3vw, 1.6rem);
  font-weight: 400;
  color: var(--text-2);
  margin-bottom: 1.75rem;
  animation: fadeUp 0.6s ease both;
  animation-delay: 0.3s;
}

.accent-dot { color: var(--accent); }

.hero-desc {
  max-width: 520px;
  color: var(--text-2);
  font-size: 1.05rem;
  margin-bottom: 2.5rem;
  animation: fadeUp 0.6s ease both;
  animation-delay: 0.4s;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  animation: fadeUp 0.6s ease both;
  animation-delay: 0.5s;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.85rem 1.75rem;
  border-radius: var(--radius);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--accent);
  color: var(--bg);
  border-color: var(--accent);
}
.btn-primary:hover {
  background: transparent;
  color: var(--accent);
}

.btn-secondary {
  background: transparent;
  color: var(--accent);
  border-color: var(--accent);
}
.btn-secondary:hover {
  background: var(--accent-dim);
}

.hero-scroll {
  margin-top: 5rem;
  display: flex;
  justify-content: center;
  animation: fadeUp 0.6s ease both;
  animation-delay: 0.7s;
}

.scroll-line {
  width: 1px;
  height: 60px;
  background: linear-gradient(to bottom, var(--accent), transparent);
  animation: scrollPulse 2s ease infinite;
}

/* ────────────────────────────────────────────────────────────
   Section base
──────────────────────────────────────────────────────────── */
.section {
  padding: 6rem 0;
}

.section-alt {
  background: var(--bg-alt);
}

.section-title {
  font-size: clamp(1.4rem, 3vw, 1.75rem);
  font-weight: 600;
  color: var(--white);
  margin-bottom: 3rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  white-space: nowrap;
}

.section-title::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border);
  min-width: 40px;
}

.section-num {
  font-family: var(--font-mono);
  font-size: 0.95rem;
  color: var(--accent);
}

/* ────────────────────────────────────────────────────────────
   About
──────────────────────────────────────────────────────────── */
.about-grid {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 3rem;
  align-items: start;
}

.about-text p {
  color: var(--text-2);
  margin-bottom: 1.25rem;
  font-size: 1.02rem;
}
.about-text p:last-child { margin-bottom: 0; }

.about-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  min-width: 240px;
}

.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.25rem 1rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  transition: border-color var(--transition), transform var(--transition);
}
.stat-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.stat-number {
  font-family: var(--font-mono);
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 0.4rem;
}

.stat-label {
  font-size: 0.72rem;
  color: var(--text-2);
  text-transform: uppercase;
  letter-spacing: 0.07em;
}

/* ────────────────────────────────────────────────────────────
   Timeline
──────────────────────────────────────────────────────────── */
.timeline {
  position: relative;
  padding-left: 2rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(to bottom, var(--accent), var(--border) 80%, transparent);
}

.timeline-item {
  position: relative;
  margin-bottom: 3rem;
}
.timeline-item:last-child { margin-bottom: 0; }

.timeline-dot {
  position: absolute;
  left: -2.4rem;
  top: 1.1rem;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--bg-alt);
  box-shadow: 0 0 0 3px var(--accent-dim);
}

.timeline-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  transition: border-color var(--transition), transform var(--transition);
}
.timeline-card:hover {
  border-color: rgba(100, 255, 218, 0.3);
  transform: translateX(4px);
}

.timeline-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 1.25rem;
  flex-wrap: wrap;
}

.timeline-role {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--white);
  display: flex;
  align-items: center;
  gap: 0.6rem;
  flex-wrap: wrap;
}

.level-badge {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  background: var(--accent-dim);
  color: var(--accent);
  border: 1px solid rgba(100, 255, 218, 0.3);
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
  letter-spacing: 0.05em;
}

.timeline-company {
  margin-top: 0.3rem;
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.company-name {
  font-weight: 500;
  color: var(--accent);
  font-size: 0.92rem;
}

.company-type {
  color: var(--text-2);
  font-size: 0.88rem;
}

.timeline-date {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-2);
  white-space: nowrap;
  margin-top: 0.25rem;
}

/* Sub-roles */
.sub-role {
  margin-bottom: 1.25rem;
  padding-left: 1rem;
  border-left: 2px solid var(--border);
}
.sub-role:last-of-type { margin-bottom: 1.25rem; }

.sub-role-title {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-1);
  margin-bottom: 0.6rem;
}

.sub-date {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-2);
  display: block;
  margin-top: 0.2rem;
}

/* Bullets */
.timeline-bullets {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  margin-bottom: 0;
}

.timeline-bullets li {
  font-size: 0.93rem;
  color: var(--text-2);
  padding-left: 1.1rem;
  position: relative;
}

.timeline-bullets li::before {
  content: '▸';
  position: absolute;
  left: 0;
  color: var(--accent);
  font-size: 0.7rem;
  top: 0.25rem;
}

/* Tags */
.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1.25rem;
}

.tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent);
  background: var(--accent-dim);
  border: 1px solid rgba(100, 255, 218, 0.2);
  padding: 0.25rem 0.65rem;
  border-radius: 4px;
}

/* ────────────────────────────────────────────────────────────
   Skills
──────────────────────────────────────────────────────────── */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.5rem;
}

.skill-group {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  transition: border-color var(--transition), transform var(--transition);
}
.skill-group:hover {
  border-color: rgba(100, 255, 218, 0.3);
  transform: translateY(-2px);
}

.skill-group-title {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 1rem;
}

.skill-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.pill {
  font-size: 0.82rem;
  color: var(--text-1);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
  padding: 0.3rem 0.75rem;
  border-radius: 999px;
  transition: border-color var(--transition), color var(--transition);
}
.pill:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* ────────────────────────────────────────────────────────────
   Education
──────────────────────────────────────────────────────────── */
.edu-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2rem;
  max-width: 640px;
  transition: border-color var(--transition), transform var(--transition);
}
.edu-card:hover {
  border-color: rgba(100, 255, 218, 0.3);
  transform: translateY(-2px);
}

.edu-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 0.75rem;
  flex-wrap: wrap;
}

.edu-school {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--white);
}

.edu-location {
  font-size: 0.88rem;
  color: var(--text-2);
  margin-top: 0.2rem;
}

.edu-degree {
  font-size: 1rem;
  color: var(--accent);
  margin-bottom: 0.75rem;
}

.edu-activities {
  font-size: 0.87rem;
  color: var(--text-2);
}

/* ────────────────────────────────────────────────────────────
   Contact
──────────────────────────────────────────────────────────── */
.contact-wrapper {
  max-width: 540px;
}

.contact-desc {
  font-size: 1.05rem;
  color: var(--text-2);
  margin-bottom: 2rem;
}

.contact-links {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.contact-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.8rem 1.5rem;
  border: 1px solid var(--accent);
  border-radius: var(--radius);
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: 0.88rem;
  transition: background var(--transition);
}
.contact-btn:hover {
  background: var(--accent-dim);
}

/* ────────────────────────────────────────────────────────────
   Footer
──────────────────────────────────────────────────────────── */
.footer {
  padding: 2.5rem 2rem;
  text-align: center;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-3);
  border-top: 1px solid var(--border);
}

/* ────────────────────────────────────────────────────────────
   Animations
──────────────────────────────────────────────────────────── */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(24px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes scrollPulse {
  0%, 100% { opacity: 1; transform: scaleY(1); }
  50%       { opacity: 0.4; transform: scaleY(0.8); }
}

.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ────────────────────────────────────────────────────────────
   Responsive
──────────────────────────────────────────────────────────── */
@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: var(--nav-h);
    left: 0;
    right: 0;
    background: rgba(10, 15, 30, 0.98);
    flex-direction: column;
    align-items: center;
    gap: 0;
    padding: 1.5rem 0;
    border-bottom: 1px solid var(--border);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: transform var(--transition), opacity var(--transition);
  }
  .nav-links.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }
  .nav-links li {
    width: 100%;
    text-align: center;
  }
  .nav-link {
    display: block;
    padding: 1rem;
    font-size: 0.95rem;
  }
  .nav-cta {
    display: inline-flex;
    margin-top: 0.5rem;
  }
  .nav-toggle { display: flex; }

  .nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .nav-toggle.open span:nth-child(2) { opacity: 0; }
  .nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

  .hero { padding-top: calc(var(--nav-h) + 4rem); }

  .about-grid {
    grid-template-columns: 1fr;
  }
  .about-stats {
    grid-template-columns: repeat(4, 1fr);
    min-width: unset;
  }

  .timeline { padding-left: 1.5rem; }
  .timeline-dot { left: -1.9rem; }

  .timeline-header { flex-direction: column; }

  .skills-grid { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .about-stats { grid-template-columns: 1fr 1fr; }
  .section { padding: 4rem 0; }
}