/* ─── Custom Properties ─────────────────────────────────────────────────── */
:root {
  --bg:           #0f172a;
  --bg-alt:       #0b1120;
  --surface:      #1e293b;
  --surface-2:    #263348;
  --border:       #2d3f55;
  --text:         #f1f5f9;
  --text-muted:   #94a3b8;
  --text-faint:   #64748b;
  --accent:       #38bdf8;
  --accent-2:     #818cf8;
  --accent-glow:  rgba(56, 189, 248, 0.12);
  --gradient:     linear-gradient(135deg, #38bdf8 0%, #818cf8 100%);
  --nav-h:        68px;
  --radius:       12px;
  --radius-sm:    8px;
  --transition:   0.25s ease;
  --shadow:       0 4px 24px rgba(0, 0, 0, 0.4);
  --shadow-lg:    0 8px 48px rgba(0, 0, 0, 0.6);
}

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

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

body {
  font-family: 'Inter', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
ul { list-style: none; }
img, svg { display: block; }

/* ─── Typography ────────────────────────────────────────────────────────── */
h1, h2, h3, h4 { line-height: 1.25; font-weight: 700; }
p { color: var(--text-muted); }
strong { color: var(--text); font-weight: 600; }

/* ─── Utility ───────────────────────────────────────────────────────────── */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 100px 0;
}
.section-alt {
  background: var(--bg-alt);
}

.section-header {
  margin-bottom: 56px;
}
.section-tag {
  display: inline-block;
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 12px;
}
.section-title {
  font-size: clamp(1.75rem, 3vw, 2.5rem);
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ─── Scroll Reveal ─────────────────────────────────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ─── Buttons ───────────────────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: transform var(--transition), box-shadow var(--transition), background var(--transition);
  border: none;
}
.btn:hover { transform: translateY(-2px); }

.btn-primary {
  background: var(--gradient);
  color: #0f172a;
}
.btn-primary:hover { box-shadow: 0 6px 24px rgba(56, 189, 248, 0.35); }

.btn-secondary {
  background: transparent;
  color: var(--text);
  border: 1.5px solid var(--border);
}
.btn-secondary:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-glow);
}

.btn-ghost {
  background: transparent;
  color: var(--text-muted);
  border: 1.5px solid var(--border);
}
.btn-ghost:hover {
  border-color: var(--text-muted);
  color: var(--text);
}

/* ─── Badge ─────────────────────────────────────────────────────────────── */
.badge {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 100px;
  font-size: 0.8rem;
  font-weight: 500;
  background: var(--surface-2);
  color: var(--text-muted);
  border: 1px solid var(--border);
}
.badge-gold {
  background: rgba(250, 204, 21, 0.1);
  color: #facc15;
  border-color: rgba(250, 204, 21, 0.3);
}

/* ─── Navigation ────────────────────────────────────────────────────────── */
#navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  height: var(--nav-h);
  transition: background var(--transition), box-shadow var(--transition), backdrop-filter var(--transition);
}
#navbar.scrolled {
  background: rgba(15, 23, 42, 0.92);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  box-shadow: 0 1px 0 var(--border);
}

.nav-container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-family: 'JetBrains Mono', monospace;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.02em;
  transition: color var(--transition);
}
.nav-logo:hover { color: var(--accent); }
.logo-bracket {
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav-link {
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-muted);
  transition: color var(--transition), background var(--transition);
}
.nav-link:hover, .nav-link.active {
  color: var(--text);
  background: var(--surface);
}
.nav-cta {
  margin-left: 8px;
  background: var(--gradient) !important;
  color: #0f172a !important;
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  font-weight: 600;
}
.nav-cta:hover { box-shadow: 0 4px 16px rgba(56, 189, 248, 0.3); }

.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}
.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}
.hamburger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.open span:nth-child(2) { opacity: 0; }
.hamburger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ─── Hero ──────────────────────────────────────────────────────────────── */
#hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: calc(var(--nav-h) + 40px) 24px 80px;
  background:
    radial-gradient(ellipse 80% 60% at 50% -20%, rgba(56, 189, 248, 0.08) 0%, transparent 70%),
    linear-gradient(-45deg, #0f172a, #111e35, #0f1f2e, #131c35);
  background-size: 400% 400%;
  animation: bgShift 18s ease infinite;
  position: relative;
  overflow: hidden;
}
#hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: radial-gradient(circle, rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 40px 40px;
  pointer-events: none;
}

@keyframes bgShift {
  0%   { background-position: 0% 50%; }
  50%  { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 760px;
}

.hero-greeting {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.9rem;
  color: var(--accent);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.hero-name {
  font-size: clamp(3rem, 7vw, 5.5rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.05;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 20px;
}

.hero-role {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0;
  font-size: clamp(1rem, 2.5vw, 1.4rem);
  font-weight: 500;
  color: var(--text-muted);
  min-height: 2.2rem;
  margin-bottom: 20px;
}
.typing-text {
  font-family: 'JetBrains Mono', monospace;
  color: var(--text);
}
.cursor {
  display: inline-block;
  width: 2px;
  height: 1.2em;
  background: var(--accent);
  margin-left: 3px;
  animation: blink 1s step-start infinite;
  border-radius: 1px;
}
@keyframes blink {
  50% { opacity: 0; }
}

.hero-meta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 36px;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-bottom: 48px;
}

.hero-stats {
  display: inline-flex;
  align-items: center;
  gap: 32px;
  padding: 20px 36px;
  background: rgba(30, 41, 59, 0.6);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  backdrop-filter: blur(8px);
}
.stat { text-align: center; }
.stat-num {
  display: block;
  font-size: 1.75rem;
  font-weight: 800;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  margin-bottom: 4px;
}
.stat-lbl {
  display: block;
  font-size: 0.75rem;
  color: var(--text-faint);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}
.stat-sep {
  width: 1px;
  height: 40px;
  background: var(--border);
}

.scroll-hint {
  position: absolute;
  bottom: 36px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  font-size: 0.7rem;
  color: var(--text-faint);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  font-family: 'JetBrains Mono', monospace;
  animation: fadeInUp 1.5s ease 1s both;
}
.scroll-line {
  width: 1px;
  height: 40px;
  background: linear-gradient(to bottom, var(--text-faint), transparent);
  animation: scrollPulse 2s ease infinite;
}
@keyframes scrollPulse {
  0%, 100% { opacity: 1; transform: scaleY(1); transform-origin: top; }
  50% { opacity: 0.4; transform: scaleY(0.6); transform-origin: top; }
}
@keyframes fadeInUp {
  from { opacity: 0; transform: translateX(-50%) translateY(12px); }
  to   { opacity: 1; transform: translateX(-50%) translateY(0); }
}

/* ─── About ─────────────────────────────────────────────────────────────── */
.about-layout {
  display: grid;
  grid-template-columns: 1fr 380px;
  gap: 56px;
  align-items: start;
}
.about-text p {
  margin-bottom: 18px;
  font-size: 1.0rem;
  line-height: 1.8;
}
.about-text p:last-child { margin-bottom: 0; }
.about-target {
  padding: 16px 20px;
  border-left: 3px solid var(--accent);
  background: var(--accent-glow);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin-top: 4px !important;
}

.about-highlights {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.highlight-card {
  display: flex;
  gap: 16px;
  align-items: flex-start;
  padding: 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color var(--transition), transform var(--transition);
}
.highlight-card:hover {
  border-color: var(--accent);
  transform: translateX(4px);
}
.highlight-icon {
  font-size: 1.5rem;
  flex-shrink: 0;
  margin-top: 2px;
}
.highlight-card h4 {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 4px;
}
.highlight-card p {
  font-size: 0.82rem;
  line-height: 1.5;
  color: var(--text-muted);
}

/* ─── Skills ────────────────────────────────────────────────────────────── */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 20px;
}
.skill-category {
  padding: 24px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color var(--transition), box-shadow var(--transition);
}
.skill-category:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow);
}
.skill-cat-title {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 16px;
}
.skill-cat-title span { font-size: 1.1rem; }

.skill-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.tag {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 100px;
  font-size: 0.8rem;
  font-weight: 500;
  background: var(--surface-2);
  color: var(--text-muted);
  border: 1px solid var(--border);
  transition: border-color var(--transition), color var(--transition);
}
.tag:hover { border-color: var(--accent); color: var(--text); }
.tag-primary {
  background: rgba(56, 189, 248, 0.08);
  color: var(--accent);
  border-color: rgba(56, 189, 248, 0.25);
}
.tag-primary:hover { background: rgba(56, 189, 248, 0.15); }

/* ─── Experience Timeline ───────────────────────────────────────────────── */
.timeline {
  position: relative;
  padding-left: 28px;
}
.timeline::before {
  content: '';
  position: absolute;
  left: 7px; top: 8px; bottom: 8px;
  width: 2px;
  background: linear-gradient(to bottom, var(--accent), var(--accent-2), transparent);
  border-radius: 2px;
}

.timeline-item {
  position: relative;
  margin-bottom: 48px;
}
.timeline-item:last-child { margin-bottom: 0; }

.tl-marker {
  position: absolute;
  left: -28px; top: 22px;
  width: 16px; height: 16px;
  border-radius: 50%;
  background: var(--bg);
  border: 2.5px solid var(--accent);
  transition: background var(--transition), box-shadow var(--transition);
}
.timeline-item:hover .tl-marker {
  background: var(--accent);
  box-shadow: 0 0 0 4px var(--accent-glow);
}

.tl-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 32px;
  transition: border-color var(--transition), box-shadow var(--transition);
}
.tl-card:hover {
  border-color: rgba(56, 189, 248, 0.35);
  box-shadow: var(--shadow);
}

.tl-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}
.tl-company {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text);
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 4px;
}
.tl-title {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-muted);
}
.tl-date {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.78rem;
  color: var(--accent);
  background: rgba(56, 189, 248, 0.1);
  border: 1px solid rgba(56, 189, 248, 0.2);
  padding: 4px 12px;
  border-radius: 100px;
  white-space: nowrap;
  flex-shrink: 0;
}

.tl-bullets {
  display: flex;
  flex-direction: column;
  gap: 20px;
}
.tl-bullets li {
  padding-left: 20px;
  border-left: 2px solid var(--border);
  transition: border-color var(--transition);
}
.tl-bullets li:hover { border-color: var(--accent); }

.tl-bullets p {
  font-size: 0.9rem;
  line-height: 1.75;
  margin-bottom: 10px;
  color: var(--text-muted);
}

.tech-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.tech-pills span {
  display: inline-block;
  padding: 2px 10px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.72rem;
  font-weight: 500;
  color: var(--text-faint);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 4px;
}

/* ─── Education ─────────────────────────────────────────────────────────── */
.edu-card {
  display: flex;
  align-items: center;
  gap: 28px;
  padding: 36px 40px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  max-width: 600px;
  transition: border-color var(--transition), box-shadow var(--transition);
}
.edu-card:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow);
}
.edu-logo {
  width: 110px;
  height: auto;
  flex-shrink: 0;
  border-radius: 6px;
}
.edu-body h3 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 6px;
}
.edu-degree {
  font-size: 1rem;
  color: var(--text-muted);
  margin-bottom: 14px;
}
.edu-meta { display: flex; gap: 10px; flex-wrap: wrap; }

/* ─── Patent ────────────────────────────────────────────────────────────── */
.patent-card {
  padding: 36px 40px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  max-width: 720px;
  transition: border-color var(--transition), box-shadow var(--transition);
}
.patent-card:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow);
}

.patent-badge-wrap {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
}
.patent-badge {
  display: inline-block;
  padding: 4px 14px;
  border-radius: 100px;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  background: var(--gradient);
  color: #0f172a;
}
.patent-num {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.85rem;
  color: var(--accent);
}
.patent-title {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text);
  line-height: 1.5;
  margin-bottom: 8px;
}
.patent-role {
  font-size: 0.85rem;
  color: var(--accent);
  font-weight: 500;
  margin-bottom: 16px;
}
.patent-desc {
  font-size: 0.9rem;
  line-height: 1.75;
  margin-bottom: 20px;
}
.patent-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--accent);
  transition: gap var(--transition);
}
.patent-link:hover { gap: 10px; }

/* ─── Contact ───────────────────────────────────────────────────────────── */
#contact { padding: 60px 0; }
.contact-wrap { max-width: 760px; }
.contact-sub {
  font-size: 1rem;
  line-height: 1.75;
  margin-bottom: 40px;
}
.contact-cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
}
.contact-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 24px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
}
.contact-card:hover {
  border-color: var(--accent);
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}
.contact-icon { font-size: 1.6rem; line-height: 1; }
.contact-icon svg { width: 2rem; height: 2rem; display: block; }
.contact-label {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-faint);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.contact-value {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text);
  word-break: break-all;
}

/* ─── Footer ────────────────────────────────────────────────────────────── */
.footer {
  padding: 32px 0;
  border-top: 1px solid var(--border);
}
.footer p {
  text-align: center;
  font-size: 0.82rem;
  color: var(--text-faint);
}

/* ─── Responsive ────────────────────────────────────────────────────────── */
@media (max-width: 900px) {
  .about-layout {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .hamburger { display: flex; }

  .nav-links {
    display: none;
    position: absolute;
    top: var(--nav-h);
    left: 0; right: 0;
    flex-direction: column;
    gap: 0;
    background: rgba(15, 23, 42, 0.98);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border);
    padding: 8px 0 16px;
  }
  .nav-links.open { display: flex; }
  .nav-link {
    padding: 12px 24px;
    border-radius: 0;
    width: 100%;
  }
  .nav-cta {
    margin: 0;
    width: 100%;
    background: transparent !important;
    color: var(--text-muted) !important;
    padding: 12px 24px;
    border-radius: 0;
    font-weight: 400;
    box-shadow: none !important;
  }

  .hero-stats {
    gap: 20px;
    padding: 16px 24px;
  }

  .tl-header {
    flex-direction: column;
    gap: 10px;
  }

  .tl-card { padding: 20px 20px; }

  .edu-card {
    flex-direction: column;
    align-items: flex-start;
    padding: 24px;
  }

  .patent-card { padding: 24px; }

  .section { padding: 72px 0; }
}

@media (max-width: 480px) {
  .hero-cta { flex-direction: column; align-items: stretch; }
  .btn { justify-content: center; }
}