.calculator-panel {
  display: grid;
  gap: var(--space-4);
}

.calculator-panel form {
  display: grid;
  gap: var(--space-3);
}

.calculator-panel label {
  display: grid;
  gap: 0.5rem;
  color: var(--text);
  font-weight: 500;
}

.calculator-panel input,
.calculator-panel select,
.calculator-panel textarea {
  width: 100%;
  border: 1px solid rgba(33, 107, 47, 0.14);
  background: var(--surface-soft);
  border-radius: 16px;
  padding: 1rem 1.2rem;
  color: var(--text);
}

.calculator-panel input:focus,
.calculator-panel select:focus,
.calculator-panel textarea:focus {
  outline: 2px solid rgba(33, 107, 47, 0.18);
}

.calculator-panel button {
  width: fit-content;
  border-radius: 999px;
}

.result-box {
  background: var(--surface);
  border: 1px solid rgba(33, 107, 47, 0.08);
  border-radius: var(--radius-card);
  padding: var(--space-5);
  box-shadow: var(--shadow);
  display: grid;
  gap: 0.9rem;
}

.result-box .formula,
.result-box .explanation,
.result-box .result-summary {
  padding: 0.95rem 1rem;
  border-radius: var(--radius-md);
  background: var(--surface-soft);
  border: 1px solid rgba(33, 107, 47, 0.08);
}

.result-box h3 {
  margin-top: 0;
}

.calculator-grid {
  display: grid;
  grid-template-columns: minmax(280px, 1fr) 1.25fr;
  gap: var(--space-4);
}

.validation-message {
  min-height: 1.25rem;
  color: var(--color-primary);
  font-weight: 600;
}

.validation-message.error {
  color: var(--color-danger);
}

.calculator-actions,
.history-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.history-panel {
  margin-top: 1rem;
  border-top: 1px solid rgba(33, 107, 47, 0.1);
  padding-top: 1rem;
}

.history-item {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: center;
  padding: 0.75rem 0;
  border-bottom: 1px solid rgba(33, 107, 47, 0.08);
}

.history-item p {
  margin: 0.2rem 0 0;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.result-lines {
  margin: 0;
  padding-left: 1rem;
  color: var(--text-muted);
}

@media (max-width: 840px) {
  .calculator-grid {
    grid-template-columns: 1fr;
  }
}