.calculator {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.calc-card {
  min-height: 220px;
  padding: 24px;
  display: grid;
  align-content: start;
  gap: 14px;
  border: 1px solid rgba(255, 255, 255, 0.13);
  background: linear-gradient(145deg, rgba(19, 43, 74, 0.95), rgba(13, 35, 64, 0.92));
  box-shadow: 0 24px 70px rgba(0, 0, 0, 0.22);
}

.calc-card span {
  color: var(--muted);
  font-size: 14px;
  font-weight: 800;
  text-transform: uppercase;
}

.calc-card strong,
.calc-card select {
  color: var(--lime);
  font-size: clamp(32px, 3.8vw, 56px);
  font-weight: 900;
}

.calc-card small {
  color: var(--muted);
  font-size: 15px;
  line-height: 1.35;
}

.calc-card input {
  width: 100%;
  accent-color: var(--lime);
}

.calc-card select {
  width: 100%;
  border: 0;
  outline: 0;
  background: transparent;
}

.calc-card.result {
  border-color: rgba(210, 254, 8, 0.4);
}

@media (max-width: 900px) {
  .calculator {
    grid-template-columns: 1fr;
  }
}