/* KaiPlay page stylesheet — e-ink paper-calm identity with neo-brutalist flashcards */

.kp-hero {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  padding: 100px 0 80px;
}
.kp-hero-copy h1 {
  font-size: clamp(52px, 7.5vw, 84px);
  margin-top: 16px;
}
.kp-hero-copy h1 span {
  color: var(--muted);
}
.kp-lead {
  margin: 24px 0 28px;
  font-size: clamp(18px, 2vw, 22px);
  color: var(--muted);
  line-height: 1.45;
}

.kp-stage {
  min-height: 500px;
  display: grid;
  place-items: center;
  position: relative;
  overflow: hidden;
  border-radius: 28px;
  border: 1px solid #cfd0c9;
  background: #e9e9e3;
  color: #171717;
  padding: 30px;
}
.kp-stage::before, .kp-stage::after {
  content: "";
  position: absolute;
  border-radius: 50%;
}
.kp-stage::before {
  width: 260px;
  height: 260px;
  left: -80px;
  bottom: -70px;
  background: #babbb5;
}
.kp-stage::after {
  width: 180px;
  height: 180px;
  right: -40px;
  top: -30px;
  background: #d6d7d1;
}

.kp-eink-badge {
  position: absolute;
  left: 22px;
  top: 20px;
  z-index: 3;
  padding: 6px 12px;
  border: 2px solid #171717;
  background: #fff;
  font: 800 10px/1 ui-monospace, monospace;
  letter-spacing: .14em;
  border-radius: 6px;
}

.kp-card-stack {
  position: relative;
  z-index: 1;
  width: min(80%, 310px);
  aspect-ratio: 3 / 4;
}

.kp-card {
  position: absolute;
  inset: 0;
  padding: 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  border: 4px solid #171717;
  border-radius: 26px;
  background: #fff;
  box-shadow: 12px 12px 0 #171717;
  transition: transform .3s cubic-bezier(0.175, 0.885, 0.32, 1.275), opacity .3s ease;
}
.kp-card-back-a {
  transform: rotate(-7deg) translate(-15px, 10px);
  z-index: 1;
  opacity: 0.85;
}
.kp-card-back-b {
  transform: rotate(5deg) translate(12px, -8px);
  z-index: 2;
  opacity: 0.92;
}
.kp-card-front {
  transform: rotate(2deg);
  z-index: 3;
}
.kp-card-front:hover {
  transform: rotate(0deg) scale(1.03);
}

.kp-card img {
  width: 140px;
  height: 140px;
  object-fit: cover;
  border-radius: 18px;
  border: 2px solid #171717;
  filter: contrast(1.1);
}
.kp-card strong {
  margin-top: 14px;
  font-size: 26px;
  letter-spacing: -.03em;
  color: #171717;
}
.kp-card small {
  color: #555e6b;
  font-size: 16px;
  font-weight: 600;
}
.kp-sound {
  width: 42px;
  height: 42px;
  margin-top: 14px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: #171717;
  color: #fff;
  font-size: 13px;
  cursor: pointer;
  transition: transform .15s ease;
}
.kp-sound:hover {
  transform: scale(1.1);
}

.kp-switcher {
  display: flex;
  gap: 10px;
  margin-top: 20px;
  z-index: 4;
  position: relative;
}
.kp-switch-btn {
  padding: 7px 14px;
  border: 2px solid #171717;
  border-radius: 999px;
  background: #fff;
  color: #171717;
  font-weight: 700;
  font-size: 13px;
  cursor: pointer;
  transition: background .2s, color .2s;
}
.kp-switch-btn.active, .kp-switch-btn:hover {
  background: #171717;
  color: #fff;
}

.kp-principles {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  padding: 40px 0 80px;
}
.kp-note {
  border: 1px solid var(--line);
  border-radius: 20px;
  background: var(--surface);
  padding: 28px;
  transition: transform .2s ease, border-color .2s ease;
}
.kp-note:hover {
  transform: translateY(-4px);
  border-color: var(--cyan);
}
.kp-note h3 {
  margin: 0 0 10px;
  font-size: 20px;
  letter-spacing: -.03em;
}
.kp-note p {
  margin: 0;
  color: var(--muted);
  font-size: 15px;
}

.kp-features {
  padding: 80px 0;
  border-top: 1px solid var(--line);
}
.kp-feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 40px;
}
.kp-feature {
  border: 1px solid var(--line);
  border-radius: 20px;
  background: var(--surface);
  padding: 28px;
}
.kp-feature strong {
  display: block;
  font-size: 20px;
  letter-spacing: -.03em;
  margin-bottom: 8px;
}
.kp-feature span {
  color: var(--muted);
  font-size: 15px;
}

.kp-parents {
  padding: 80px 0 100px;
  border-top: 1px solid var(--line);
}
.kp-parents-card {
  border: 1px solid var(--line);
  border-radius: 28px;
  background: radial-gradient(circle at 10% 20%, #151d2a 0, #0f131c 100%);
  padding: 48px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
}
.kp-parents-copy h2 {
  font-size: clamp(32px, 4vw, 48px);
  margin-top: 10px;
}
.kp-parents-copy p {
  color: var(--muted);
  font-size: 17px;
  margin: 18px 0 28px;
}
.kp-parent-specs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
.kp-spec-item {
  padding: 16px 20px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--bg);
}
.kp-spec-item strong {
  display: block;
  font-size: 15px;
  color: var(--cyan);
}
.kp-spec-item span {
  font-size: 13px;
  color: var(--muted);
}

.kp-cta {
  display: inline-flex;
  gap: 14px;
  align-items: center;
  padding: 13px 24px;
  border-radius: 999px;
  font-weight: 750;
  text-decoration: none;
  color: var(--bg);
  background: var(--cyan);
}
.kp-cta:hover, .kp-cta:focus-visible {
  filter: brightness(1.1);
}

@media (max-width: 760px) {
  .kp-hero {
    grid-template-columns: 1fr;
    gap: 40px;
    padding-top: 60px;
  }
  .kp-principles, .kp-feature-grid {
    grid-template-columns: 1fr;
  }
  .kp-parents-card {
    grid-template-columns: 1fr;
    padding: 28px;
  }
  .kp-parent-specs {
    grid-template-columns: 1fr;
  }
}