let billingSteps = “”; const currencySymbol = “$”, fixedCurrency = “USD”; function calculateBilling() { billingSteps = “”; const hours = parseFloat(document.getElementById(“hoursWorked”).value); const rate = parseFloat(document.getElementById(“ratePerHour”).value); const extra = parseFloat(document.getElementById(“extraFees”).value); if (isNaN(hours) || isNaN(rate) || isNaN(extra) || hours <= 0 || rate <= 0) { alert("Please enter valid positive values for all fields."); return; } const totalAmount = (hours * rate) + extra; document.getElementById("totalAmount").value = formatCurrency(totalAmount); billingSteps += `Inputs:
Hours Worked: ${hours}
Rate Per Hour: ${formatCurrency(rate)}
Additional Fees: ${formatCurrency(extra)}

`; billingSteps += `Formula:
Total Amount = (Hours Worked × Rate Per Hour) + Additional Fees

`; billingSteps += `Result:
Total Amount: ${formatCurrency(totalAmount)}
`; if (document.getElementById(“calculationStepsBilling”).style.display === “block”) { document.getElementById(“calculationStepsBilling”).innerHTML = billingSteps; } } function resetBilling() { document.querySelectorAll(“#calculator input”).forEach(el => el.value = “”); billingSteps = “”; document.getElementById(“calculationStepsBilling”).innerHTML = “

Not calculated yet.

“; } function toggleBillingSteps() { const s = document.getElementById(“calculationStepsBilling”); const a = document.getElementById(“toggleArrowBilling”); if (s.style.display === “none” || s.style.display === “”) { s.style.display = “block”; a.style.transform = “rotate(180deg)”; s.innerHTML = billingSteps || “

Not calculated yet.

“; } else { s.style.display = “none”; a.style.transform = “rotate(0deg)”; } } function formatCurrency(n) { return currencySymbol + n.toFixed(2) + ” ” + fixedCurrency; }