/* BabyVocab — its own neo-brutalist E-Ink identity on the shared dark shell.
   High-contrast cream cards with hard black borders and offset shadows. */

body { --bv-ink: #171717; --bv-paper: #e9e9e3; --bv-card: #ffffff; }

.bv-hero {
  display: grid;
  grid-template-columns: 1.02fr .98fr;
  gap: 56px;
  align-items: center;
  padding: 92px 0 80px;
}
.bv-hero h1 { font-size: clamp(50px, 8vw, 100px); }
.bv-hero h1 span { color: var(--muted); }
.bv-lead { max-width: 540px; margin: 30px 0 22px; color: var(--muted); font-size: clamp(17px, 2vw, 21px); }

/* Stage: a cream play mat holding a small fanned deck of real flashcards */
.bv-stage {
  position: relative;
  aspect-ratio: 1 / 1;
  display: grid;
  place-items: center;
  border-radius: 28px;
  border: 1px solid #cfd0c9;
  background: var(--bv-paper);
  overflow: hidden;
}
.bv-stage .eink-badge { position: absolute; left: 22px; top: 20px; z-index: 5; padding: 6px 10px; border: 2px solid var(--bv-ink); background: #fff; color: var(--bv-ink); font: 800 10px/1 ui-monospace, monospace; letter-spacing: .13em; }

.bv-card {
  position: absolute;
  width: min(56%, 250px);
  margin: 0;
  padding: 16px 16px 20px;
  background: var(--bv-card);
  border: 4px solid var(--bv-ink);
  border-radius: 22px;
  box-shadow: 12px 12px 0 var(--bv-ink);
  text-align: center;
}
.bv-card img { width: 100%; height: auto; border-radius: 12px; display: block; filter: grayscale(.15) contrast(1.05); }
.bv-card strong { display: block; margin-top: 12px; font-size: 24px; letter-spacing: -.03em; color: var(--bv-ink); }
.bv-card small { display: block; margin-top: 2px; color: #69717c; font-size: 15px; }
.bv-card-front { z-index: 4; transform: rotate(3deg); }
.bv-card-back-a { z-index: 2; transform: translate(-42%, -12%) rotate(-11deg) scale(.86); opacity: .96; }
.bv-card-back-b { z-index: 3; transform: translate(40%, 10%) rotate(9deg) scale(.9); opacity: .98; }
.bv-sound { position: absolute; right: -14px; bottom: 34px; width: 46px; height: 46px; display: grid; place-items: center; border-radius: 50%; border: 4px solid var(--bv-ink); background: var(--yellow); color: var(--bv-ink); font-size: 15px; }

main > section + section { border-top: 1px solid #ffffff12; }
.bv-principles, .bv-features, .bv-parents { padding: 78px 0; }

.bv-principles { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.bv-note { padding: 26px; border: 1px solid var(--line); border-radius: 18px; background: var(--surface); }
.bv-note h3 { margin: 0 0 10px; font-size: 19px; letter-spacing: -.03em; }
.bv-note p { margin: 0; color: var(--muted); font-size: 15px; }

.bv-features h2 { font-size: clamp(34px, 5vw, 56px); letter-spacing: -.05em; margin: 0 0 36px; }
.bv-feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.bv-feature { padding: 24px; border: 1px solid var(--line); border-radius: 18px; background: var(--surface); }
.bv-feature strong { display: block; font-size: 18px; letter-spacing: -.02em; }
.bv-feature span { display: block; margin-top: 8px; color: var(--muted); font-size: 14px; }

.bv-parents-card { max-width: 760px; margin-inline: auto; padding: 44px 40px; border: 4px solid var(--bv-ink); border-radius: 26px; background: #fff; box-shadow: 14px 14px 0 var(--bv-ink); color: var(--bv-ink); text-align: center; }
.bv-parents-card .eyebrow { color: #c8792f; }
.bv-parents-card h2 { font-size: clamp(30px, 4.5vw, 48px); letter-spacing: -.04em; margin: 12px 0 14px; color: var(--bv-ink); }
.bv-parents-card p { margin: 0 auto 26px; max-width: 560px; color: #3a3f47; font-size: 17px; }
.bv-cta { display: inline-flex; gap: 12px; align-items: center; padding: 13px 22px; border-radius: 999px; font-weight: 800; text-decoration: none; color: #fff; background: var(--bv-ink); }
.bv-cta:hover, .bv-cta:focus-visible { filter: brightness(1.2); }

@media (max-width: 860px) {
  .bv-hero { grid-template-columns: 1fr; gap: 40px; padding-top: 68px; }
  .bv-stage { order: -1; max-width: 440px; }
  .bv-principles, .bv-feature-grid { grid-template-columns: 1fr; }
}