.mrc-calculator-wrapper {
  box-sizing: border-box;
  width: 100%;
  max-width: 20rem;
  margin: 1.5rem auto;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  color: #f9fafb;
  line-height: 1.4;
}

.mrc-calculator-wrapper *,
.mrc-calculator-wrapper *::before,
.mrc-calculator-wrapper *::after {
  box-sizing: border-box;
}

.mrc-calculator {
  width: 100%;
  background: #111827;
  padding: 1rem;
  border-radius: 1rem;
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.3);
  position: relative;
}

.mrc-display-wrapper {
  position: relative;
  background: #000;
  text-align: right;
  padding: 1.25rem;
  border-radius: 0.75rem;
  margin-bottom: 0.75rem;
}

.mrc-history-toggle {
  position: absolute;
  left: 0.5rem;
  top: 1.25rem;
  background: none;
  border: none;
  color: #9ca3af;
  font-size: 1.25rem;
  cursor: pointer;
  padding: 0.25rem;
  line-height: 1;
}

.mrc-history-toggle:hover,
.mrc-history-toggle:focus-visible {
  color: #fff;
  outline: none;
}

.mrc-display {
  font-size: clamp(1rem, 4vw, 1.25rem);
  overflow-x: auto;
  white-space: nowrap;
  min-height: 1.5rem;
  scrollbar-width: thin;
}

.mrc-history-panel {
  background: #1f2937;
  padding: 0.75rem;
  border-radius: 0.5rem;
  margin-bottom: 0.75rem;
  font-size: 0.875rem;
}

.mrc-history-header {
  display: flex;
  justify-content: flex-end;
  margin-bottom: 0.375rem;
}

.mrc-history-clear {
  background: none;
  border: 1px solid #4b5563;
  color: #9ca3af;
  font-size: 0.7rem;
  padding: 0.15rem 0.5rem;
  border-radius: 0.25rem;
  cursor: pointer;
  line-height: 1.4;
}

.mrc-history-clear:hover,
.mrc-history-clear:focus-visible {
  color: #f87171;
  border-color: #f87171;
  outline: none;
}

.mrc-history-scroll {
  max-height: 8rem;
  overflow-y: auto;
}

.mrc-hidden {
  display: none !important;
}

.mrc-history-empty {
  color: #9ca3af;
  margin: 0;
}

.mrc-history-item {
  border-bottom: 1px solid #374151;
  padding: 0.25rem 0;
  cursor: pointer;
}

.mrc-history-item:hover {
  color: #60a5fa;
}

.mrc-button-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 0.5rem;
  padding: 0.75rem 0 0;
}

.mrc-calc-btn {
  background: #374151;
  color: #fff;
  border: none;
  padding: 0.65rem 0.25rem;
  border-radius: 0.375rem;
  font-size: clamp(0.95rem, 3.5vw, 1.25rem);
  cursor: pointer;
  transition: background 0.15s ease;
  min-height: 2.75rem;
  touch-action: manipulation;
}

.mrc-calc-btn:hover,
.mrc-calc-btn:focus-visible {
  background: #4b5563;
  outline: none;
}

.mrc-calc-btn.mrc-equals {
  border: 1px solid #4ade80;
  color: #4ade80;
  font-weight: 600;
}

@media (max-width: 360px) {
  .mrc-calculator {
    padding: 0.75rem;
  }

  .mrc-button-grid {
    gap: 0.35rem;
  }

  .mrc-calc-btn {
    min-height: 2.5rem;
    padding: 0.5rem 0.15rem;
  }
}

@media (min-width: 768px) {
  .mrc-calculator-wrapper {
    max-width: 22rem;
  }
}