/* ============================================================
   WPC Design System — style.css
   Shared across all pages. Loaded AFTER Tailwind CDN.
   ============================================================ */

/* --- Google Fonts --- */
@import url('https://fonts.googleapis.com/css2?family=DM+Serif+Display:ital@0;1&family=Inter:wght@400;500;600;700;800&family=JetBrains+Mono:wght@400;500&display=swap');

/* --- Design Tokens --- */
:root {
  /* Palette — extracted from research materials */
  --c-deep:       #0c1525;   /* night sky (moth light-trap experiments) */
  --c-primary:    #14294b;   /* deep navy — kept for continuity */
  --c-teal:       #0d9488;   /* structural iridescence — butterfly wings */
  --c-amber:      #d97706;   /* multispectral amber channel */
  --c-coral:      #dc2626;   /* climate velocity warm shift (sparse use) */
  --c-blue:       #2563eb;   /* data / links */

  --c-bg:         #faf8f5;   /* warm white — specimen paper */
  --c-surface:    #ffffff;
  --c-surface-alt:#f5f0eb;   /* warm off-white cards */
  --c-text:       #1a1a2e;
  --c-text-2:     #5c5c6f;   /* secondary text */
  --c-text-3:     #94909e;   /* tertiary / captions */
  --c-border:     #e8e4de;

  /* Typography */
  --f-display: 'DM Serif Display', Georgia, 'Times New Roman', serif;
  --f-body:    'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --f-mono:    'JetBrains Mono', 'Fira Code', monospace;
}

/* --- Base Resets --- */
html { scroll-behavior: smooth; }
body {
  background: var(--c-bg);
  color: var(--c-text);
  font-family: var(--f-body);
  -webkit-font-smoothing: antialiased;
}

/* --- Typography --- */
h1, h2, h3, .display-font { font-family: var(--f-display); }
h1 { font-size: 3rem; line-height: 1.1; letter-spacing: -0.02em; }
h2 { font-size: 2.25rem; line-height: 1.15; }
h3 { font-size: 1.5rem; line-height: 1.25; }
@media (min-width: 768px) {
  h1 { font-size: 3.75rem; }
  h2 { font-size: 2.75rem; }
}
code, .mono { font-family: var(--f-mono); font-size: 0.85em; }

/* --- Shared Navbar --- */
.wpc-nav {
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--c-border);
}
.wpc-nav-brand {
  font-family: var(--f-display);
  font-size: 1.35rem;
  color: var(--c-primary);
  text-decoration: none;
}
.nav-link {
  padding: .45rem .85rem;
  border-radius: .5rem;
  color: var(--c-text-2);
  font-weight: 500;
  font-size: 0.9rem;
  transition: background .15s ease, color .15s ease;
  text-decoration: none;
}
.nav-link:hover { background: var(--c-surface-alt); color: var(--c-primary); }
.nav-active {
  padding: .45rem .85rem;
  border-radius: .5rem;
  background: var(--c-primary);
  color: #fff;
  font-weight: 600;
  font-size: 0.9rem;
}

/* --- Shared Footer --- */
.wpc-footer {
  background: var(--c-deep);
  color: #a3a1b0;
}
.wpc-footer a { color: #a3a1b0; transition: color .15s; text-decoration: none; }
.wpc-footer a:hover { color: #fff; }
.wpc-footer .footer-brand {
  font-family: var(--f-display);
  font-size: 1.25rem;
  color: #fff;
}

/* --- Accent Bar --- */
.accent-bar {
  width: 4rem; height: .25rem; border-radius: 9999px;
  background: linear-gradient(90deg, var(--c-teal), var(--c-amber));
}
.accent-bar-white {
  width: 4rem; height: .25rem; border-radius: 9999px;
  background: linear-gradient(90deg, rgba(255,255,255,.6), rgba(255,255,255,.3));
}

/* --- Skill Cards (Technical Skills section) --- */
.skill-card {
  background: var(--c-surface);
  border-radius: 1rem;
  overflow: hidden;
  display: flex;
  border-left: 3px solid #b2dfdb;
  box-shadow: 0 2px 12px -4px rgba(20,20,40,.08);
  transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
}
.skill-card:hover {
  transform: translateY(-4px);
  border-color: var(--c-teal);
  box-shadow: 0 12px 28px -8px rgba(13,148,136,.15);
}

/* --- Cards --- */
.card {
  background: var(--c-surface);
  border-radius: 1rem;
  box-shadow: 0 4px 20px -8px rgba(20,20,40,.12);
  transition: transform .25s ease, box-shadow .25s ease;
}
.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 20px 40px -16px rgba(20,20,40,.22);
}
.card-flat {
  background: var(--c-surface);
  border-radius: 1rem;
  border: 1px solid var(--c-border);
}

/* --- Hero Gradients --- */
.hero-immersive {
  position: relative;
  background: var(--c-deep);
  overflow: hidden;
}
.hero-immersive::before {
  content: '';
  position: absolute; inset: 0;
  background: linear-gradient(
    180deg,
    rgba(12,21,37,.6) 0%,
    rgba(12,21,37,.35) 40%,
    rgba(12,21,37,.75) 100%
  );
  z-index: 1;
}
.hero-immersive > * { position: relative; z-index: 2; }
.hero-bg-img {
  position: absolute; inset: 0;
  width: 100%; height: 100%;
  object-fit: cover;
  opacity: 0.55;
  z-index: 0;
}
.hero-gradient-dark {
  background: linear-gradient(135deg, var(--c-deep) 0%, var(--c-primary) 100%);
}

/* --- Chips / Tags --- */
.chip-glow {
  display: inline-block; font-size: .72rem; padding: .25rem .7rem;
  border-radius: 9999px;
  background: rgba(13,148,136,.15);
  color: var(--c-teal);
  border: 1px solid rgba(13,148,136,.3);
  font-weight: 500;
}
.chip-outline {
  display: inline-block; font-size: .72rem; padding: .25rem .7rem;
  border-radius: 9999px;
  background: rgba(255,255,255,.08);
  color: rgba(255,255,255,.85);
  border: 1px solid rgba(255,255,255,.25);
}
.tag-sm {
  display: inline-block; font-size: .7rem; padding: .2rem .6rem;
  border-radius: 9999px;
  background: var(--c-surface-alt);
  color: var(--c-text-2);
}

/* --- Section Titles --- */
.section-title {
  font-family: var(--f-display);
  text-align: center;
  color: var(--c-text);
}
.section-subtitle {
  text-align: center;
  color: var(--c-text-2);
  max-width: 36rem;
  margin: 0.5rem auto 0;
}

/* --- Category Headers (projects page) --- */
.cat-head {
  display: flex; align-items: center; gap: .6rem;
  font-family: var(--f-display);
  font-size: 1.5rem; font-weight: 700; color: var(--c-text);
  border-left: 4px solid var(--c-teal);
  padding-left: .75rem; margin-bottom: 1.5rem;
}

/* --- Scroll Reveal Animations --- */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}
.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }

/* Staggered children */
.reveal-stagger > .reveal { transition-delay: calc(var(--i, 0) * 0.08s); }

/* --- Dark Sections --- */
.section-dark {
  background: var(--c-deep);
  color: #e2e0ec;
}
.section-dark h3, .section-dark h2 { color: #fff; }
.section-dark .accent-bar {
  background: linear-gradient(90deg, var(--c-teal), var(--c-amber));
}

/* --- Capability Story Cards --- */
.capability-card {
  display: flex; gap: 1.5rem; align-items: flex-start;
  padding: 1.5rem;
  background: var(--c-surface);
  border-radius: 1rem;
  border: 1px solid var(--c-border);
  transition: border-color .2s, box-shadow .2s;
}
.capability-card:hover {
  border-color: var(--c-teal);
  box-shadow: 0 8px 24px -12px rgba(13,148,136,.2);
}
.capability-icon {
  flex-shrink: 0;
  width: 3rem; height: 3rem;
  border-radius: .75rem;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.25rem;
}
.capability-card h4 {
  font-family: var(--f-body);
  font-weight: 700;
  font-size: 1rem;
  margin-bottom: .35rem;
}
.capability-card p {
  font-size: .88rem;
  color: var(--c-text-2);
  line-height: 1.55;
}
.capability-evidence {
  margin-top: .5rem;
  font-family: var(--f-mono);
  font-size: .75rem;
  color: var(--c-teal);
  opacity: .85;
}

/* --- Timeline (Background section) --- */
.timeline-item {
  position: relative;
  padding-left: 2rem;
  padding-bottom: 1.75rem;
  border-left: 2px solid var(--c-border);
}
.timeline-item:last-child { border-left-color: transparent; }
.timeline-dot {
  position: absolute;
  left: -7px; top: 4px;
  width: 12px; height: 12px;
  border-radius: 50%;
  background: var(--c-teal);
  border: 2px solid var(--c-bg);
}
.timeline-dot-alt { background: var(--c-amber); }

/* --- Publication Cards --- */
.pub-item {
  padding: 1.25rem 1.5rem;
  background: var(--c-surface);
  border-radius: 0.75rem;
  border: 1px solid var(--c-border);
  transition: border-color .2s, transform .2s;
}
.pub-item:hover {
  border-color: var(--c-teal);
  transform: translateY(-2px);
}
.pub-item a { color: var(--c-teal); text-decoration: none; }
.pub-item a:hover { text-decoration: underline; }
.pub-venue { font-style: italic; color: var(--c-text-3); font-size: .85rem; }

/* --- Responsive helpers --- */
@media (max-width: 767px) {
  .capability-card { flex-direction: column; gap: .75rem; }
  .hide-mobile { display: none; }
}

/* --- Smooth link underlines --- */
a.link-teal {
  color: var(--c-teal);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color .2s;
}
a.link-teal:hover { border-bottom-color: var(--c-teal); }

/* --- Button styles --- */
.btn-primary {
  display: inline-flex; align-items: center; gap: .5rem;
  background: var(--c-teal);
  color: #fff;
  font-weight: 600;
  padding: .7rem 1.5rem;
  border-radius: 9999px;
  text-decoration: none;
  transition: background .2s, transform .2s, box-shadow .2s;
}
.btn-primary:hover {
  background: #0f766e;
  transform: translateY(-1px);
  box-shadow: 0 8px 20px -8px rgba(13,148,136,.4);
}
.btn-outline-white {
  display: inline-flex; align-items: center; gap: .5rem;
  border: 1.5px solid rgba(255,255,255,.5);
  color: #fff;
  font-weight: 500;
  padding: .6rem 1.3rem;
  border-radius: 9999px;
  text-decoration: none;
  transition: background .2s, border-color .2s;
}
.btn-outline-white:hover {
  background: rgba(255,255,255,.12);
  border-color: rgba(255,255,255,.8);
}

/* --- Scroll reveal init script (inline at bottom of each page) --- */
/*
  Add this script to each page:

  <script>
  const ro = new IntersectionObserver((entries) => {
    entries.forEach(e => { if (e.isIntersecting) { e.target.classList.add('visible'); ro.unobserve(e.target); }});
  }, { threshold: 0.1 });
  document.querySelectorAll('.reveal').forEach(el => ro.observe(el));
  </script>
*/