/* ═══════════════════════════════════════════════
   P31 LABS — PHOSPHORUS-31
   The Only Stable Isotope
   ═══════════════════════════════════════════════ */

/* ── TOKENS ── */
:root {
  --void: #050510;
  --void-up: #0a0a1a;
  --void-surface: #0f0f24;
  --void-border: #1a1a3a;
  --phosphorus: #2ecc71;
  --phosphorus-dim: #1a7a43;
  --phosphorus-glow: rgba(46, 204, 113, 0.15);
  --phosphorus-flare: rgba(46, 204, 113, 0.4);
  --calcium: #60a5fa;
  --calcium-dim: #2563eb;
  --calcium-glow: rgba(96, 165, 250, 0.12);
  --white: #e8e8f0;
  --white-dim: #9898b0;
  --white-muted: #585870;
  --font-display: 'Outfit', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* ── RESET ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
body {
  font-family: var(--font-display);
  background: var(--void);
  color: var(--white);
  line-height: 1.6;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; }

.sr-only {
  position: absolute; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}

/* ── SKIP LINK ── */
.skip-link {
  position: absolute;
  top: -100px;
  left: 0;
  z-index: 1000;
  padding: 0.75rem 1.5rem;
  background: var(--phosphorus);
  color: var(--void);
  font-family: var(--font-mono);
  font-size: 0.875rem;
  font-weight: 600;
  text-decoration: none;
  border-radius: 0 0 4px 0;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 0;
  outline: 3px solid var(--calcium);
  outline-offset: 2px;
}

/* ── LAYOUT ── */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 clamp(1.5rem, 4vw, 3rem);
}

.section {
  padding: clamp(5rem, 12vh, 10rem) 0;
  position: relative;
}

.section-dark {
  background: var(--void-up);
  border-top: 1px solid var(--void-border);
  border-bottom: 1px solid var(--void-border);
}

/* ── CANVAS LAYERS ── */
#mesh-bg {
  position: fixed;
  top: 0; left: 0;
  width: 100vw; height: 100vh;
  z-index: 0;
  pointer-events: none;
  opacity: 0.6;
}

#hero-geometry {
  position: absolute;
  top: 0; right: 0;
  width: 50vw; height: 100vh;
  z-index: 1;
  pointer-events: none;
  opacity: 0.8;
  mask-image: radial-gradient(ellipse 80% 70% at 60% 50%, black 30%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse 80% 70% at 60% 50%, black 30%, transparent 70%);
}

/* ── NAV ── */
nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  padding: 1rem 0;
  background: linear-gradient(to bottom, var(--void) 0%, transparent 100%);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: background 0.3s ease;
}

.nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 clamp(1.5rem, 4vw, 3rem);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--phosphorus);
  letter-spacing: -0.02em;
  text-shadow: 0 0 20px var(--phosphorus-glow), 0 0 40px rgba(46, 204, 113, 0.08);
  transition: text-shadow 0.3s ease;
}
.nav-logo:hover {
  text-shadow: 0 0 20px var(--phosphorus-flare), 0 0 60px var(--phosphorus-glow);
}
.nav-logo sup {
  font-size: 0.6em;
  color: var(--calcium);
  vertical-align: super;
}

.nav-links {
  display: flex;
  gap: 2rem;
}
.nav-links a {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 400;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--white-dim);
  transition: color 0.2s ease;
  position: relative;
}
.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px; left: 0;
  width: 0; height: 1px;
  background: var(--phosphorus);
  transition: width 0.3s var(--ease-out-expo);
  box-shadow: 0 0 8px var(--phosphorus-glow);
}
.nav-links a:hover { color: var(--white); }
.nav-links a:hover::after { width: 100%; }

/* ── HERO ── */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  z-index: 2;
  padding: 6rem 0 4rem;
}

.hero-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 clamp(1.5rem, 4vw, 3rem);
  position: relative;
}

.hero-equation {
  font-family: var(--font-mono);
  font-size: clamp(0.75rem, 1.2vw, 0.9rem);
  color: var(--phosphorus);
  letter-spacing: 0.1em;
  margin-bottom: 2rem;
  opacity: 0;
  animation: fadeSlideUp 0.8s var(--ease-out-expo) 0.2s forwards;
  text-shadow: 0 0 30px var(--phosphorus-glow);
}

.hero h1 {
  font-size: clamp(2.5rem, 6vw, 5rem);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -0.03em;
  max-width: 700px;
  opacity: 0;
  animation: fadeSlideUp 1s var(--ease-out-expo) 0.4s forwards;
}

.hero h1 em {
  font-style: normal;
  background: linear-gradient(135deg, var(--phosphorus) 0%, var(--calcium) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-pre {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(0.65rem, 1vw, 0.8rem);
  font-weight: 400;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  color: var(--white-muted);
  margin-bottom: 0.75rem;
  -webkit-text-fill-color: var(--white-muted);
}

.hero-sub {
  font-size: clamp(1rem, 1.8vw, 1.2rem);
  font-weight: 300;
  color: var(--white-dim);
  max-width: 560px;
  margin-top: 1.5rem;
  line-height: 1.7;
  opacity: 0;
  animation: fadeSlideUp 1s var(--ease-out-expo) 0.6s forwards;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  margin-top: 2.5rem;
  opacity: 0;
  animation: fadeSlideUp 1s var(--ease-out-expo) 0.8s forwards;
}

/* Buttons */
.btn {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 500;
  padding: 0.85rem 1.8rem;
  border-radius: 2px;
  letter-spacing: 0.04em;
  transition: all 0.3s var(--ease-out-expo);
  position: relative;
  overflow: hidden;
}

.btn-primary {
  background: var(--phosphorus);
  color: var(--void);
  box-shadow: 0 0 30px var(--phosphorus-glow), inset 0 1px 0 rgba(255,255,255,0.15);
}
.btn-primary:hover {
  background: #34d67d;
  box-shadow: 0 0 50px var(--phosphorus-flare), 0 4px 20px rgba(46, 204, 113, 0.3);
  transform: translateY(-1px);
}

.btn-primary:focus {
  outline: 2px solid var(--calcium);
  outline-offset: 2px;
}

.btn-primary.copied {
  background: var(--calcium);
  box-shadow: 0 0 30px var(--calcium-glow), 0 4px 12px rgba(0,0,0,0.3);
}

.btn-ghost {
  background: transparent;
  color: var(--white-dim);
  border: 1px solid var(--void-border);
}
.btn-ghost:hover {
  color: var(--white);
  border-color: var(--phosphorus-dim);
  box-shadow: 0 0 20px var(--phosphorus-glow);
}

/* Isotope element card */
.hero-isotope {
  position: absolute;
  bottom: -2rem;
  right: 0;
  width: 140px;
  padding: 1rem;
  border: 1px solid var(--void-border);
  background: rgba(5, 5, 16, 0.8);
  text-align: center;
  opacity: 0;
  animation: fadeIn 1.5s ease 1.2s forwards;
}

.isotope-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--white-muted);
}
.isotope-symbol {
  display: block;
  font-family: var(--font-display);
  font-size: 3rem;
  font-weight: 800;
  color: var(--phosphorus);
  line-height: 1;
  text-shadow: 0 0 40px var(--phosphorus-glow);
}
.isotope-mass {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--white-dim);
  margin-top: 0.25rem;
}
.isotope-note {
  display: block;
  font-size: 0.55rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--white-muted);
  margin-top: 0.5rem;
  border-top: 1px solid var(--void-border);
  padding-top: 0.5rem;
}

/* ── METRICS ── */
.metrics {
  position: relative;
  z-index: 2;
  padding: 3rem 0;
  border-top: 1px solid var(--void-border);
  border-bottom: 1px solid var(--void-border);
  background: var(--void-up);
}

.metrics-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  text-align: center;
}

.metric-val {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.8rem, 3vw, 2.5rem);
  font-weight: 700;
  color: var(--phosphorus);
  text-shadow: 0 0 30px var(--phosphorus-glow);
}

.metric-unit {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--white-muted);
  margin-top: 0.3rem;
}

/* ── SECTION HEADERS ── */
.section-header {
  margin-bottom: 4rem;
}

.section-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--phosphorus);
  display: block;
  margin-bottom: 1rem;
}

.section-header h2 {
  font-size: clamp(2rem, 4.5vw, 3.5rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.1;
}

.section-header p {
  font-size: 1.1rem;
  font-weight: 300;
  color: var(--white-dim);
  margin-top: 1rem;
  max-width: 600px;
  line-height: 1.7;
}

/* ── STACK CARDS ── */
.stack-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 1.5rem;
}

.stack-card {
  position: relative;
  padding: 2rem;
  background: var(--void-up);
  border: 1px solid var(--void-border);
  border-radius: 3px;
  overflow: hidden;
  transition: all 0.4s var(--ease-out-expo);
}

.stack-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--phosphorus), var(--calcium), var(--phosphorus));
  background-size: 200% 100%;
  opacity: 0;
  transition: opacity 0.4s ease;
  animation: shimmer 3s linear infinite;
}

.stack-card:hover {
  border-color: var(--phosphorus-dim);
  transform: translateY(-4px);
  box-shadow:
    0 0 40px var(--phosphorus-glow),
    0 20px 60px rgba(0, 0, 0, 0.4);
}
.stack-card:hover::before { opacity: 1; }

.card-glow {
  position: absolute;
  top: -50%; left: -50%;
  width: 200%; height: 200%;
  background: radial-gradient(circle at var(--mouse-x, 50%) var(--mouse-y, 50%),
    var(--phosphorus-glow) 0%, transparent 50%);
  opacity: 0;
  transition: opacity 0.4s ease;
  pointer-events: none;
}
.stack-card:hover .card-glow { opacity: 1; }

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
}

.card-tag {
  font-family: var(--font-mono);
  font-size: 0.6rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  color: var(--phosphorus);
  background: rgba(46, 204, 113, 0.08);
  padding: 0.3rem 0.7rem;
  border: 1px solid rgba(46, 204, 113, 0.15);
  border-radius: 1px;
}

.card-reg {
  font-family: var(--font-mono);
  font-size: 0.6rem;
  color: var(--white-muted);
  letter-spacing: 0.05em;
}

.stack-card h3 {
  font-size: 1.6rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
  letter-spacing: -0.01em;
}

.stack-card p {
  font-size: 0.95rem;
  color: var(--white-dim);
  line-height: 1.7;
  font-weight: 300;
}

.card-tech {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1.5rem;
}

.card-tech span {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--calcium);
  background: var(--calcium-glow);
  padding: 0.25rem 0.6rem;
  border-radius: 1px;
  letter-spacing: 0.04em;
}

.card-formula {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--white-muted);
  margin-top: 1.5rem;
  padding-top: 1rem;
  border-top: 1px solid var(--void-border);
  opacity: 0.5;
  letter-spacing: 0.02em;
}

/* ── GEOMETRY SECTION ── */
.geometry-showcase {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-bottom: 4rem;
}

#jitterbug-canvas {
  width: 100%;
  max-width: 600px;
  height: 400px;
  border: 1px solid var(--void-border);
  border-radius: 3px;
  background: rgba(5, 5, 16, 0.6);
  cursor: grab;
}
#jitterbug-canvas:active { cursor: grabbing; }

.geometry-controls {
  width: 100%;
  max-width: 600px;
  margin-top: 1.5rem;
  padding: 0 0.5rem;
}

/* Range slider */
input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 2px;
  background: var(--void-border);
  outline: none;
  border-radius: 1px;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px; height: 16px;
  background: var(--phosphorus);
  border-radius: 50%;
  cursor: pointer;
  box-shadow: 0 0 15px var(--phosphorus-glow), 0 0 30px rgba(46, 204, 113, 0.1);
  transition: box-shadow 0.2s ease;
}
input[type="range"]::-webkit-slider-thumb:hover {
  box-shadow: 0 0 20px var(--phosphorus-flare), 0 0 40px var(--phosphorus-glow);
}
input[type="range"]::-moz-range-thumb {
  width: 16px; height: 16px;
  background: var(--phosphorus);
  border-radius: 50%;
  border: none;
  cursor: pointer;
  box-shadow: 0 0 15px var(--phosphorus-glow);
}

.morph-labels {
  display: flex;
  justify-content: space-between;
  margin-top: 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--white-muted);
  letter-spacing: 0.06em;
}
.morph-mid { color: var(--calcium); }

/* Math blocks */
.math-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
}

.math-block {
  padding: 1.5rem;
  background: rgba(5, 5, 16, 0.5);
  border: 1px solid var(--void-border);
  border-radius: 3px;
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}
.math-block:hover {
  border-color: var(--phosphorus-dim);
  box-shadow: 0 0 30px var(--phosphorus-glow);
}

.math-title {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--phosphorus);
  margin-bottom: 0.75rem;
}

.math-eq {
  font-family: var(--font-mono);
  font-size: clamp(0.85rem, 1.4vw, 1.05rem);
  font-weight: 500;
  color: var(--white);
  padding: 0.75rem 0;
  letter-spacing: 0.02em;
  text-shadow: 0 0 20px var(--phosphorus-glow);
}

.math-desc {
  font-size: 0.85rem;
  font-weight: 300;
  color: var(--white-dim);
  line-height: 1.65;
  margin-top: 0.5rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--void-border);
}

/* ── WHY SECTION ── */
.why-content {
  max-width: 800px;
}

blockquote {
  font-size: clamp(1.2rem, 2.5vw, 1.8rem);
  font-weight: 300;
  font-style: italic;
  line-height: 1.5;
  color: var(--white);
  padding-left: 2rem;
  border-left: 3px solid var(--phosphorus);
  margin-bottom: 3rem;
  text-shadow: 0 0 40px rgba(46, 204, 113, 0.05);
}

.why-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  margin-bottom: 3rem;
}

.why-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  color: var(--phosphorus);
  text-shadow: 0 0 30px var(--phosphorus-glow);
  line-height: 1;
}

.why-desc {
  display: block;
  font-size: 0.8rem;
  color: var(--white-dim);
  margin-top: 0.5rem;
  line-height: 1.5;
}

.why-text p {
  font-size: 1.05rem;
  font-weight: 300;
  color: var(--white-dim);
  line-height: 1.8;
  margin-bottom: 1.25rem;
}

/* ── FOUNDER ── */
.founder-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: start;
}

.founder-info h3 {
  font-size: 1.8rem;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.founder-title {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--phosphorus);
  letter-spacing: 0.06em;
  margin-top: 0.25rem;
  margin-bottom: 1.25rem;
}

.founder-info p {
  font-size: 1rem;
  font-weight: 300;
  color: var(--white-dim);
  line-height: 1.7;
  margin-bottom: 1rem;
}

.founder-stack {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  align-content: start;
}

.founder-tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  padding: 0.6rem 1rem;
  border: 1px solid var(--void-border);
  border-radius: 2px;
  color: var(--white-dim);
  background: rgba(5, 5, 16, 0.5);
  transition: all 0.3s ease;
}
.founder-tag:hover {
  border-color: var(--phosphorus-dim);
  color: var(--phosphorus);
  box-shadow: 0 0 20px var(--phosphorus-glow);
}

/* ── CONTACT ── */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1rem;
}

.contact-link {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1.5rem;
  border: 1px solid var(--void-border);
  border-radius: 3px;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--white-dim);
  transition: all 0.3s var(--ease-out-expo);
}
.contact-link:hover {
  border-color: var(--phosphorus-dim);
  color: var(--white);
  transform: translateY(-2px);
  box-shadow: 0 0 30px var(--phosphorus-glow), 0 10px 30px rgba(0,0,0,0.3);
}

.contact-icon {
  font-size: 1.4rem;
  color: var(--phosphorus);
  width: 2.5rem;
  height: 2.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(46, 204, 113, 0.2);
  border-radius: 50%;
  flex-shrink: 0;
}

/* ── FOOTER ── */
footer {
  padding: 3rem 0;
  border-top: 1px solid var(--void-border);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer-logo {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--phosphorus-dim);
  font-size: 1rem;
}
.footer-logo sup { font-size: 0.5em; color: var(--calcium-dim); }

.footer-legal {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--white-muted);
  margin-left: 1.5rem;
  letter-spacing: 0.06em;
}

.footer-tagline {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--white-muted);
}

.footer-formula {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--white-muted);
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--void-border);
  opacity: 0.5;
  text-align: center;
  letter-spacing: 0.04em;
}

.footer-sponsor {
  font-size: 0.75rem;
  color: var(--white-dim);
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--void-border);
  line-height: 1.6;
  text-align: center;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

/* ── ELEMENT CARD ── */
.element-card-wrapper {
  display: flex;
  justify-content: center;
  margin-top: 2rem;
}

.element-card {
  width: 200px;
  padding: 2rem;
  border: 1px solid var(--void-border);
  background: rgba(5, 5, 16, 0.6);
  text-align: center;
  border-radius: 3px;
  transition: all 0.4s var(--ease-out-expo);
}

.element-card:hover {
  border-color: var(--phosphorus-dim);
  box-shadow: 0 0 40px var(--phosphorus-glow);
  transform: translateY(-4px);
}

.element-num {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--white-muted);
  margin-bottom: 0.5rem;
}

.element-symbol {
  font-family: var(--font-display);
  font-size: 4rem;
  font-weight: 800;
  color: var(--phosphorus);
  line-height: 1;
  text-shadow: 0 0 40px var(--phosphorus-glow);
  margin-bottom: 0.5rem;
}

.element-name {
  font-size: 1rem;
  font-weight: 600;
  color: var(--white);
  margin-bottom: 0.5rem;
}

.element-mass {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--white-dim);
  margin-bottom: 0.75rem;
}

.element-formula {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--calcium);
  margin-bottom: 0.75rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--void-border);
}

.element-note {
  font-size: 0.65rem;
  color: var(--white-muted);
  line-height: 1.5;
  letter-spacing: 0.02em;
}

/* ── ECONOMY GRID ── */
.economy-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.economy-card {
  padding: 2rem;
  background: var(--void-up);
  border: 1px solid var(--void-border);
  border-radius: 3px;
  transition: all 0.4s var(--ease-out-expo);
}

.economy-card:hover {
  border-color: var(--phosphorus-dim);
  box-shadow: 0 0 30px var(--phosphorus-glow);
  transform: translateY(-2px);
}

.economy-icon {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  display: block;
}

.economy-card h3 {
  font-size: 1.3rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
  color: var(--white);
}

.economy-card p {
  font-size: 0.9rem;
  color: var(--white-dim);
  line-height: 1.7;
  margin-bottom: 1rem;
}

.economy-metric {
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--void-border);
}

.economy-val {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--phosphorus);
  text-shadow: 0 0 30px var(--phosphorus-glow);
  margin-bottom: 0.25rem;
}

.economy-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--white-muted);
}

/* ── DONATE SECTION ── */
.donate-content {
  max-width: 1000px;
  margin: 0 auto;
}

.donate-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-bottom: 2.5rem;
}

.donate-option {
  padding: 2rem;
  background: var(--void-surface);
  border: 1px solid var(--void-border);
  border-radius: 3px;
  text-align: center;
  display: flex;
  flex-direction: column;
}

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

.donate-option-header h3 {
  font-size: 1.3rem;
  font-weight: 600;
  color: var(--white);
  margin: 0;
}

.donate-badge {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  padding: 0.35rem 0.7rem;
  border-radius: 2px;
  letter-spacing: 0.04em;
  font-weight: 500;
  white-space: nowrap;
}

.donate-badge-tax {
  background: var(--phosphorus-glow);
  border: 1px solid rgba(46, 204, 113, 0.3);
  color: var(--phosphorus);
}

.donate-badge-crypto {
  background: var(--calcium-glow);
  border: 1px solid rgba(96, 165, 250, 0.3);
  color: var(--calcium);
}

.donate-option-desc {
  font-size: 0.9rem;
  color: var(--white-dim);
  line-height: 1.6;
  margin-bottom: 1.5rem;
  flex-grow: 1;
}

.donate-btn {
  margin-bottom: 1rem;
  width: 100%;
}

.donate-option-note {
  font-size: 0.8rem;
  color: var(--white-muted);
  line-height: 1.5;
  margin-top: auto;
}

.donate-wallet {
  padding: 1.5rem;
  background: rgba(5, 5, 16, 0.4);
  border: 1px solid var(--void-border);
  border-radius: 3px;
  margin-bottom: 1rem;
}

.wallet-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--white-muted);
  margin-bottom: 0.75rem;
}

.wallet-address {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  user-select: all;
  cursor: text;
  color: var(--phosphorus);
  word-break: break-all;
  margin-bottom: 1rem;
  padding: 0.875rem;
  background: rgba(5, 5, 16, 0.6);
  border: 1px solid var(--void-border);
  border-radius: 2px;
}

.donate-networks {
  display: flex;
  justify-content: center;
  gap: 0.75rem;
  margin-bottom: 0;
  flex-wrap: wrap;
}

.network-badge {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  padding: 0.4rem 0.8rem;
  background: var(--calcium-glow);
  border: 1px solid rgba(96, 165, 250, 0.2);
  border-radius: 2px;
  color: var(--calcium);
  letter-spacing: 0.04em;
}

.donate-disclosure {
  padding: 1.5rem;
  background: var(--void-up);
  border: 1px solid var(--void-border);
  border-radius: 3px;
  text-align: left;
}

.donate-disclosure p {
  font-size: 0.85rem;
  color: var(--white-dim);
  line-height: 1.6;
  margin: 0;
}

.donate-disclosure strong {
  color: var(--white);
  font-weight: 600;
}

/* ── FOOTER LINKS ── */
.foot-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  margin-top: 2rem;
  padding-top: 2rem;
  border-top: 1px solid var(--void-border);
  justify-content: center;
}

.foot-links a {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--white-dim);
  letter-spacing: 0.04em;
  transition: color 0.2s ease;
}

.foot-links a:hover {
  color: var(--phosphorus);
}

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

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* Scroll reveal */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s var(--ease-out-expo), transform 0.8s var(--ease-out-expo);
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ── REDUCED MOTION ── */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* ── RESPONSIVE ── */
@media (max-width: 768px) {
  .nav-links { display: none; } /* TODO: hamburger */

  .hero-isotope { display: none; }

  #hero-geometry { display: none; }

  .metrics-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
  }

  .why-stats {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .founder-content {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .footer-inner {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }

  .footer-legal { margin-left: 0; }

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

  .element-card {
    width: 100%;
    max-width: 200px;
  }
}

@media (max-width: 480px) {
  .stack-grid { grid-template-columns: 1fr; }
  .math-grid { grid-template-columns: 1fr; }
}