/* ================================================
   CUSTOM PROPERTIES
   ================================================ */
:root {
  --bg-0: #060912;
  --bg-1: #090e1c;
  --bg-2: #0d1526;
  --bg-card: #0f1a30;
  --bg-card-hover: #131f3a;

  --blue: #2563eb;
  --blue-lt: #3b82f6;
  --cyan: #22d3ee;
  --cyan-dim: #0891b2;
  --blue-glow: rgba(37, 99, 235, 0.28);
  --cyan-glow: rgba(34, 211, 238, 0.18);

  --text-0: #f0f5ff;
  --text-1: #c4d4f0;
  --text-2: #6e8ab5;
  --text-3: #3a5078;

  --border: rgba(37, 99, 235, 0.16);
  --border-hover: rgba(34, 211, 238, 0.35);

  --r: 8px;
  --r-lg: 12px;

  --sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --mono: 'JetBrains Mono', 'Fira Code', monospace;

  --max-w: 1080px;
  --pad-section: 96px;
}

/* ================================================
   RESET
   ================================================ */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--sans);
  background: var(--bg-0);
  color: var(--text-1);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
strong { color: var(--cyan); font-weight: 600; }

/* ================================================
   UTILITIES
   ================================================ */
.container { max-width: var(--max-w); margin: 0 auto; padding: 0 28px; }
.mono { font-family: var(--mono); }
.accent { color: var(--cyan); }
.text-secondary { color: var(--text-2); }
.small { font-size: 0.78rem; }

/* ================================================
   NAV
   ================================================ */
.nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 36px;
  background: rgba(6, 9, 18, 0.82);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
  transition: background 0.3s;
}

.nav-logo {
  font-family: var(--mono);
  font-size: 1.25rem;
  font-weight: 500;
  letter-spacing: -0.02em;
}

.nav-links {
  display: flex;
  gap: 36px;
}

.nav-links a {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--text-2);
  letter-spacing: 0.06em;
  transition: color 0.2s;
}
.nav-links a:hover { color: var(--cyan); }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}
.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-1);
  border-radius: 2px;
  transition: 0.25s;
}

/* ================================================
   HERO
   ================================================ */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  padding: 130px 28px 100px;
}

/* Engineering graph-paper background */
.hero-bg {
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(ellipse at 12% 65%, rgba(37, 99, 235, 0.13) 0%, transparent 52%),
    radial-gradient(ellipse at 88% 18%, rgba(34, 211, 238, 0.07) 0%, transparent 42%),
    linear-gradient(rgba(37, 99, 235, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(37, 99, 235, 0.045) 1px, transparent 1px);
  background-size: auto, auto, 44px 44px, 44px 44px;
}

/* Faint major-grid overlay (every 4th line) */
.hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(37, 99, 235, 0.08) 1px, transparent 1px),
    linear-gradient(90deg, rgba(37, 99, 235, 0.08) 1px, transparent 1px);
  background-size: 176px 176px;
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero-greeting {
  font-size: 0.82rem;
  color: var(--cyan);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  margin-bottom: 14px;
}

.hero-name {
  font-size: clamp(3.2rem, 9vw, 6.5rem);
  font-weight: 700;
  line-height: 0.95;
  letter-spacing: -0.04em;
  color: var(--text-0);
  margin-bottom: 20px;
  /* Subtle gradient lift */
  background: linear-gradient(160deg, #ffffff 0%, #c4d4f0 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-title-row {
  margin-bottom: 28px;
  min-height: 1.8rem;
  display: flex;
  align-items: center;
  gap: 1px;
}

#typewriter {
  font-size: clamp(0.85rem, 2vw, 1.05rem);
  letter-spacing: 0.03em;
}

.cursor {
  animation: blink 0.9s step-end infinite;
  font-size: 1rem;
  line-height: 1;
}
@keyframes blink { 0%, 100% { opacity: 1; } 50% { opacity: 0; } }

.hero-bio {
  max-width: 500px;
  color: var(--text-2);
  font-size: 1.02rem;
  line-height: 1.85;
  margin-bottom: 44px;
}

.hero-ctas {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

/* ================================================
   BUTTONS
   ================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 24px;
  border-radius: var(--r);
  font-family: var(--mono);
  font-size: 0.82rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  transition: all 0.2s ease;
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: var(--blue);
  color: #fff;
}
.btn-primary:hover {
  background: var(--blue-lt);
  box-shadow: 0 0 22px var(--blue-glow);
  transform: translateY(-2px);
}

.btn-outline {
  background: transparent;
  color: var(--cyan);
  border: 1px solid var(--cyan-dim);
}
.btn-outline:hover {
  background: rgba(34, 211, 238, 0.08);
  border-color: var(--cyan);
  box-shadow: 0 0 18px var(--cyan-glow);
  transform: translateY(-2px);
}

.btn-ghost {
  background: transparent;
  color: var(--text-2);
  border: 1px solid var(--border);
}
.btn-ghost:hover {
  color: var(--text-0);
  border-color: var(--border-hover);
  transform: translateY(-2px);
}

/* ================================================
   SCROLL HINT
   ================================================ */
.scroll-hint {
  position: absolute;
  bottom: 36px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--text-3);
  font-size: 0.65rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.scroll-line {
  width: 1px;
  height: 0;
  background: linear-gradient(to bottom, var(--cyan), transparent);
  animation: scrollPulse 2s ease-in-out infinite;
}
@keyframes scrollPulse {
  0%   { height: 0;    opacity: 0; }
  40%  { height: 36px; opacity: 1; }
  100% { height: 36px; opacity: 0; }
}

/* ================================================
   SECTIONS
   ================================================ */
.section { padding: var(--pad-section) 0; }

.section-alt {
  background: var(--bg-1);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.section-title {
  font-size: clamp(1.5rem, 3.5vw, 2rem);
  font-weight: 600;
  color: var(--text-0);
  margin-bottom: 52px;
  letter-spacing: -0.025em;
}
.section-title .mono {
  font-size: 0.72em;
  margin-right: 10px;
}

/* ================================================
   ABOUT
   ================================================ */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 64px;
  align-items: start;
}

.about-text p {
  color: var(--text-2);
  font-size: 1.01rem;
  line-height: 1.9;
  margin-bottom: 20px;
}

.edu-list {
  display: flex;
  flex-direction: column;
  gap: 18px;
  margin-top: 36px;
  padding-top: 36px;
  border-top: 1px solid var(--border);
}

.edu-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
}

.edu-deg {
  flex-shrink: 0;
  font-size: 0.78rem;
  padding-top: 3px;
  letter-spacing: 0.04em;
}

.edu-item strong {
  display: block;
  color: var(--text-0);
  font-size: 0.95rem;
  font-weight: 500;
}
.edu-item .text-secondary { font-size: 0.83rem; display: block; margin-top: 2px; }

.photo-placeholder {
  aspect-ratio: 3 / 4;
  max-height: 370px;
  border: 1px dashed rgba(34, 211, 238, 0.25);
  border-radius: var(--r-lg);
  background: var(--bg-card);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  position: relative;
  overflow: hidden;
}
.photo-placeholder::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(37,99,235,0.06) 0%, transparent 60%);
}

/* ================================================
   SKILLS
   ================================================ */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.skill-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 28px 26px;
  transition: border-color 0.2s, transform 0.2s;
}
.skill-card:hover {
  border-color: var(--border-hover);
  transform: translateY(-2px);
}

.skill-heading {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-0);
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.skill-glyph { color: var(--cyan); font-size: 1.05rem; }

.chips { display: flex; flex-wrap: wrap; gap: 8px; }

.chip {
  padding: 4px 12px;
  border-radius: 4px;
  background: rgba(37, 99, 235, 0.1);
  border: 1px solid rgba(37, 99, 235, 0.22);
  color: var(--text-1);
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.02em;
  transition: all 0.18s;
}
.chip:hover {
  background: rgba(34, 211, 238, 0.1);
  border-color: rgba(34, 211, 238, 0.38);
  color: var(--cyan);
}

/* ================================================
   PROJECTS
   ================================================ */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.project-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 26px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  position: relative;
  overflow: hidden;
  transition: border-color 0.22s, transform 0.22s, box-shadow 0.22s;
}

/* Gradient top-bar that slides in on hover */
.project-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--blue), var(--cyan));
  opacity: 0;
  transition: opacity 0.22s;
}
.project-card:hover {
  border-color: rgba(37, 99, 235, 0.35);
  transform: translateY(-4px);
  box-shadow: 0 12px 36px rgba(37, 99, 235, 0.14);
}
.project-card:hover::before { opacity: 1; }

.project-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.project-num {
  font-size: 0.7rem;
  color: var(--text-3);
  letter-spacing: 0.1em;
}

.project-links { display: flex; gap: 12px; }

.icon-link {
  display: flex;
  align-items: center;
  color: var(--text-2);
  transition: color 0.18s;
}
.icon-link svg { width: 17px; height: 17px; }
.icon-link:hover { color: var(--cyan); }

.project-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-0);
  line-height: 1.3;
}

.project-desc {
  font-size: 0.875rem;
  color: var(--text-2);
  line-height: 1.75;
  flex: 1;
}

.tags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: auto; }

.tag {
  padding: 3px 10px;
  border-radius: 3px;
  background: rgba(34, 211, 238, 0.07);
  border: 1px solid rgba(34, 211, 238, 0.18);
  color: var(--cyan);
  font-family: var(--mono);
  font-size: 0.68rem;
  letter-spacing: 0.04em;
}

/* ================================================
   TIMELINE (EXPERIENCE)
   ================================================ */
.timeline {
  position: relative;
  padding-left: 36px;
}

/* Vertical spine */
.timeline::before {
  content: '';
  position: absolute;
  left: 8px; top: 10px; bottom: 10px;
  width: 1px;
  background: linear-gradient(to bottom, var(--blue) 0%, transparent 100%);
}

.tl-item {
  position: relative;
  margin-bottom: 44px;
}
.tl-item:last-child { margin-bottom: 0; }

.tl-dot {
  position: absolute;
  left: -31px;
  top: 8px;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  background: var(--blue);
  border: 2px solid var(--bg-1);
  box-shadow: 0 0 10px var(--blue-glow);
}

.tl-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 24px 28px;
  transition: border-color 0.2s;
}
.tl-card:hover { border-color: var(--border-hover); }

.tl-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 6px;
}
.tl-header h3 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-0);
}

.tl-date {
  font-size: 0.75rem;
  color: var(--cyan);
  letter-spacing: 0.06em;
  flex-shrink: 0;
}

.tl-role {
  font-size: 0.88rem;
  color: var(--text-1);
  margin-bottom: 4px;
}
.tl-loc { font-size: 0.8rem; margin-bottom: 18px; }

.tl-bullets { display: flex; flex-direction: column; gap: 9px; }
.tl-bullets li {
  font-size: 0.86rem;
  color: var(--text-2);
  padding-left: 16px;
  position: relative;
  line-height: 1.65;
}
.tl-bullets li::before {
  content: '›';
  position: absolute;
  left: 0;
  color: var(--cyan);
  font-family: var(--mono);
  font-size: 1rem;
  line-height: 1.4;
}

/* ================================================
   CONTACT
   ================================================ */
.contact-wrap {
  text-align: center;
  max-width: 560px;
}

.contact-sub {
  color: var(--text-2);
  font-size: 1.05rem;
  line-height: 1.8;
  margin-bottom: 44px;
}

.contact-links {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

.contact-btn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-family: var(--mono);
  font-size: 0.82rem;
  color: var(--text-2);
  padding: 13px 28px;
  border: 1px solid var(--border);
  border-radius: var(--r);
  transition: all 0.2s;
}
.contact-btn:hover {
  color: var(--cyan);
  border-color: var(--cyan-dim);
  background: rgba(34, 211, 238, 0.05);
  transform: translateY(-2px);
}

/* ================================================
   FOOTER
   ================================================ */
.footer {
  text-align: center;
  padding: 28px;
  border-top: 1px solid var(--border);
  font-size: 0.8rem;
}

/* ================================================
   GET TO KNOW ME
   ================================================ */
.personal-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 22px;
}

.personal-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 28px 24px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  transition: border-color 0.22s, transform 0.22s;
}
.personal-card:hover {
  border-color: var(--border-hover);
  transform: translateY(-3px);
}

.personal-icon { font-size: 1.8rem; line-height: 1; }

.personal-card h3 {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-0);
}

.personal-card p {
  font-size: 0.875rem;
  line-height: 1.7;
}

/* Headshot (swap in when photo is added) */
.headshot {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: var(--r-lg);
  display: block;
}

/* ================================================
   SCROLL FADE-UP ANIMATION
   ================================================ */
.fade-up {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}
.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Stagger children in a grid */
.projects-grid .project-card:nth-child(2) { transition-delay: 0.07s; }
.projects-grid .project-card:nth-child(3) { transition-delay: 0.14s; }
.projects-grid .project-card:nth-child(4) { transition-delay: 0.07s; }
.projects-grid .project-card:nth-child(5) { transition-delay: 0.14s; }

.skills-grid .skill-card:nth-child(2) { transition-delay: 0.08s; }
.skills-grid .skill-card:nth-child(3) { transition-delay: 0.16s; }

/* ================================================
   RESPONSIVE
   ================================================ */
@media (max-width: 920px) {
  .about-grid { grid-template-columns: 1fr; }
  .about-photo { display: none; }
  .skills-grid { grid-template-columns: 1fr 1fr; }
  .projects-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 680px) {
  :root { --pad-section: 68px; }
  .nav { padding: 14px 20px; }
  .nav-links { display: none; }
  .nav-toggle { display: flex; }

  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 57px; left: 0; right: 0;
    background: rgba(6, 9, 18, 0.97);
    border-bottom: 1px solid var(--border);
    padding: 24px 28px;
    gap: 22px;
    z-index: 199;
  }

  .hero { padding: 110px 20px 80px; }
  .hero-ctas { flex-direction: column; align-items: flex-start; }
  .skills-grid { grid-template-columns: 1fr; }
  .projects-grid { grid-template-columns: 1fr; }
  .timeline { padding-left: 28px; }
  .tl-dot { left: -24px; }
}

/* ================================================
   PDF MODAL
   ================================================ */
.pdf-modal {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 1000;
  align-items: center;
  justify-content: center;
}
.pdf-modal.open { display: flex; }

.pdf-modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(6, 9, 18, 0.88);
  backdrop-filter: blur(6px);
}

.pdf-modal-box {
  position: relative;
  display: flex;
  flex-direction: column;
  width: min(860px, 94vw);
  height: 90vh;
  background: var(--bg-card);
  border: 1px solid var(--border-hover);
  border-radius: var(--r-lg);
  overflow: hidden;
  box-shadow: 0 24px 80px rgba(0,0,0,0.6), 0 0 0 1px rgba(34,211,238,0.06);
}

.pdf-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  background: var(--bg-2);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.pdf-toolbar-title { font-size: 0.82rem; }

.pdf-toolbar-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.pdf-dl-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.82rem;
  padding: 6px 14px;
}

.pdf-close-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--r);
  color: var(--text-2);
  cursor: pointer;
  padding: 6px;
  transition: color 0.2s, border-color 0.2s;
}
.pdf-close-btn:hover { color: var(--text-0); border-color: var(--border-hover); }

.pdf-frame {
  flex: 1;
  overflow-y: auto;
  background: #e5e7eb;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 20px 0;
  gap: 12px;
}

.pdf-frame canvas {
  display: block;
  max-width: 100%;
  box-shadow: 0 4px 20px rgba(0,0,0,0.35);
}

.pdf-loading {
  margin: auto;
  font-size: 0.9rem;
}