/* ═══════════════════════════════════════════════════════════════════
   THREE PILLARS — Empire Edition service architecture
   ═══════════════════════════════════════════════════════════════════ */

.pillars {
  display: flex;
  flex-direction: column;
  gap: var(--space-16);
  margin-top: var(--space-12);
}

.pillar {
  position: relative;
  padding: var(--space-8);
  border-radius: var(--radius-xl);
  background:
    linear-gradient(180deg, rgba(13, 18, 32, 0.6) 0%, rgba(8, 11, 20, 0.8) 100%);
  border: 1px solid var(--color-bg-border);
  overflow: hidden;
  transition: border-color var(--transition-base), transform var(--transition-base);
}
.pillar::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(124, 58, 237, 0.6), transparent);
}
.pillar:hover {
  border-color: rgba(124, 58, 237, 0.25);
}

.pillar--ai {
  background:
    radial-gradient(80% 60% at 100% 0%, rgba(6, 182, 212, 0.08) 0%, transparent 60%),
    linear-gradient(180deg, rgba(13, 18, 32, 0.6) 0%, rgba(8, 11, 20, 0.8) 100%);
}
.pillar--engineering {
  background:
    radial-gradient(80% 60% at 0% 0%, rgba(37, 99, 235, 0.08) 0%, transparent 60%),
    linear-gradient(180deg, rgba(13, 18, 32, 0.6) 0%, rgba(8, 11, 20, 0.8) 100%);
}
.pillar--mrr {
  background:
    radial-gradient(80% 60% at 50% 100%, rgba(16, 185, 129, 0.08) 0%, transparent 60%),
    linear-gradient(180deg, rgba(13, 18, 32, 0.6) 0%, rgba(8, 11, 20, 0.8) 100%);
}

/* Pillar header (number, title, description, icon) */
.pillar__header {
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: var(--space-6);
  align-items: center;
  margin-bottom: var(--space-8);
}
@media (max-width: 720px) {
  .pillar__header {
    grid-template-columns: 1fr;
    gap: var(--space-4);
    text-align: left;
  }
  .pillar__icon { display: none; }
}

.pillar__num {
  font-family: 'Syne', system-ui, sans-serif;
  font-weight: 800;
  font-size: clamp(3.5rem, 7vw, 5.5rem);
  line-height: 0.9;
  letter-spacing: -0.05em;
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  opacity: 0.85;
}
.pillar--ai .pillar__num         { background: linear-gradient(135deg, #06B6D4, #7C3AED); -webkit-background-clip: text; background-clip: text; }
.pillar--engineering .pillar__num{ background: linear-gradient(135deg, #2563EB, #7C3AED); -webkit-background-clip: text; background-clip: text; }
.pillar--mrr .pillar__num        { background: linear-gradient(135deg, #06B6D4, #2563EB); -webkit-background-clip: text; background-clip: text; }

.pillar__head-content {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}
.pillar__eyebrow {
  font-family: 'Inter', system-ui, sans-serif;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-text-muted);
}
.pillar__head-content h3 {
  font-family: 'Syne', system-ui, sans-serif;
  font-weight: 700;
  font-size: clamp(1.5rem, 3vw, 2.1rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--color-text-primary);
  margin: 0;
}
.pillar__head-content p {
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  line-height: 1.55;
  margin: 0;
  max-width: 56ch;
}

.pillar__icon {
  width: 80px;
  height: 80px;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--color-bg-border);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

/* Pillar sub-cards */
.pillar__cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-4);
}
@media (min-width: 720px) {
  .pillar--engineering .pillar__cards,
  .pillar--mrr .pillar__cards {
    grid-template-columns: repeat(3, 1fr);
  }
  .pillar--ai .pillar__cards {
    grid-template-columns: repeat(2, 1fr);
  }
}

.pillar-card {
  position: relative;
  padding: var(--space-6);
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--color-bg-border);
  border-radius: var(--radius-lg);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  transition: transform var(--transition-base), border-color var(--transition-base), background var(--transition-base);
  overflow: hidden;
}
.pillar-card::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--radius-lg);
  padding: 1px;
  background: linear-gradient(135deg, transparent 50%, rgba(124, 58, 237, 0.35) 100%);
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
          mask-composite: exclude;
  opacity: 0;
  transition: opacity var(--transition-base);
  pointer-events: none;
}
.pillar-card:hover {
  transform: translateY(-4px);
  border-color: rgba(124, 58, 237, 0.3);
  background: rgba(255, 255, 255, 0.04);
}
.pillar-card:hover::after { opacity: 1; }

.pillar-card__icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: var(--color-bg-elevated);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.pillar-card h4 {
  font-family: 'Syne', system-ui, sans-serif;
  font-weight: 700;
  font-size: 1.1rem;
  line-height: 1.25;
  letter-spacing: -0.01em;
  color: var(--color-text-primary);
  margin: 0;
}
.pillar-card p {
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--color-text-secondary);
  margin: 0;
}

.pillar-card__badge {
  position: absolute;
  top: var(--space-3);
  right: var(--space-3);
  font-size: 0.62rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 3px 8px;
  border-radius: 9999px;
  background: linear-gradient(135deg, rgba(124, 58, 237, 0.15), rgba(37, 99, 235, 0.15));
  border: 1px solid rgba(124, 58, 237, 0.35);
  color: #A78BFA;
}
.pillar-card__badge--mrr {
  background: linear-gradient(135deg, rgba(16, 185, 129, 0.15), rgba(6, 182, 212, 0.15));
  border-color: rgba(16, 185, 129, 0.4);
  color: #34D399;
}