:root {
  --ink: #0C1C33;
  --muted: #5A6B7A;
  --line: #D5DEE6;
  --paper: #F3F5F7;
  --white: #FFFFFF;
  --gutter: 18px;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; }
body {
  font-family: Montserrat, Helvetica, Arial, sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.55;
}
img { max-width: 100%; height: auto; display: block; }
.wrap { width: min(1360px, calc(100% - 2 * var(--gutter))); margin: 0 auto; }

/* Header */
.mast {
  background: var(--white);
  border-bottom: 1px solid var(--line);
}
.mast-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 0;
  gap: 16px;
}
.mast-brand { display: flex; align-items: center; gap: 12px; }
.mast-brand img { width: 36px; height: 36px; border-radius: 8px; }
.mast-brand span { font-weight: 650; font-size: 14px; letter-spacing: 0.04em; }
.mast-meta { font-size: 12px; color: var(--muted); letter-spacing: 0.06em; text-transform: uppercase; font-weight: 600; }

/* Hero */
.hero { padding: 56px 0 28px; }
.eyebrow {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: #163A70;
  margin-bottom: 12px;
}
.hero h1 {
  font-size: clamp(32px, 4.6vw, 56px);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.05;
  margin-bottom: 18px;
}
.lede {
  max-width: 760px;
  font-size: 17px;
  color: #334556;
}
.lede + .lede { margin-top: 12px; }

/* Concepts grid */
.grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
  padding: 12px 0 72px;
}
.card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 16px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}
.card-head { padding: 26px 24px 8px; }
.num {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin-bottom: 6px;
}
.card h2 {
  font-size: 28px;
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 10px;
}
.rationale { font-size: 14px; color: #334556; margin-bottom: 16px; }
.meta { font-size: 12px; color: var(--muted); margin-bottom: 16px; }
.meta strong { color: var(--ink); font-weight: 650; }

/* Swatches */
.swatches { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 8px; }
.swatch { display: flex; flex-direction: column; align-items: center; gap: 6px; width: 56px; }
.chip {
  width: 44px; height: 44px; border-radius: 10px;
  border: 1px solid rgba(12,28,51,0.12);
  box-shadow: inset 0 0 0 1px rgba(255,255,255,0.25);
}
.swatch span { font-size: 9px; font-weight: 650; letter-spacing: 0.02em; color: var(--muted); text-align: center; word-break: break-all; }

/* Stages */
.stage { padding: 8px 16px 20px; }
.stage h3 {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 8px 8px;
}
.panel {
  border-radius: 12px;
  padding: 22px 18px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
}
.panel.light { background: #F7F9FB; border: 1px solid var(--line); }
.panel.dark { border: 1px solid transparent; }
.panel img.lockup { width: 100%; max-width: 340px; }
.icon-row { display: flex; align-items: flex-end; gap: 14px; }
.icon-row figure { display: flex; flex-direction: column; align-items: center; gap: 6px; }
.icon-row figcaption { font-size: 10px; color: var(--muted); font-weight: 600; }
.panel.dark .icon-row figcaption { color: rgba(255,255,255,0.65); }
.icon-row img.i80 { width: 80px; height: 80px; }
.icon-row img.i48 { width: 48px; height: 48px; }
.icon-row img.i32 { width: 32px; height: 32px; }
.mock { padding: 0 16px 20px; }
.mock h3 {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 8px 8px;
}
.mock-frame {
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--line);
  background: #E8EEF3;
}
.mock-frame.header { background: var(--white); }

/* Footer */
.foot {
  border-top: 1px solid var(--line);
  background: var(--white);
  padding: 22px 0;
  text-align: center;
  font-size: 13px;
  color: var(--muted);
}
.foot strong { color: var(--ink); font-weight: 650; }

@media (max-width: 960px) {
  .grid { grid-template-columns: 1fr; gap: 28px; }
  .hero { padding: 36px 0 12px; }
  .lede { font-size: 16px; }
}
@media (max-width: 600px) {
  .mast-meta { display: none; }
  .swatch { width: 48px; }
  .chip { width: 40px; height: 40px; }
}