.tool-card h2 {
  margin-top: 0;
}

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

.display {
  background: #f8fafc;
  border-radius: 16px;
  padding: 16px;
  border: 1px solid var(--border);
}

.display input {
  width: 100%;
  border: none;
  background: transparent;
  font-size: 18px;
  outline: none;
}

.result {
  font-size: 28px;
  font-weight: 700;
  margin-top: 8px;
  text-align: right;
}

.pad {
  display: grid;
  gap: 10px;
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.pad button {
  border-radius: 12px;
  border: 1px solid var(--border);
  padding: 14px 0;
  font-size: 16px;
  background: #ffffff;
  cursor: pointer;
  transition: all 0.2s ease;
}

.pad button:hover {
  border-color: #cbd5f5;
  box-shadow: 0 6px 18px rgba(15, 23, 42, 0.08);
}

.pad button.primary {
  background: #0f766e;
  color: white;
  border-color: #0f766e;
}

.pad button.secondary {
  background: #f1f5f9;
}

.muted {
  color: #b91c1c;
  min-height: 18px;
  margin-top: 8px;
}