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+<!doctype html>
+<html lang="en">
+<head>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <title>Bootstrap demo</title>
+    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.2.3/dist/css/bootstrap.min.css" rel="stylesheet"
+          integrity="sha384-rbsA2VBKQhggwzxH7pPCaAqO46MgnOM80zW1RWuH61DGLwZJEdK2Kadq2F9CUG65" crossorigin="anonymous">
+</head>
+<body>
+<div class="container">
+    <div class="row">
+        <div class="col">
+            <h1>Hello, world!</h1>
+            <form class="row">
+                <div class="mb-3 col-sm-6 col-md-4">
+                    <label for="idBruttoInput" class="form-label text-bold">Brutto salary*:</label>
+                    <div class="input-group">
+                        <span class="input-group-text">€</span>
+                        <input type="number" class="form-control" id="idBruttoInput" placeholder="700" min="700"
+                               step="1">
+                        <span class="input-group-text">.00</span>
+                    </div>
+
+                    <label for="idDependentsInput" class="form-label text-bold">Dependents:</label>
+                    <select id="idDependentsInput" class="form-select">
+                        <option value="0" selected>0</option>
+                        <option value="1">1</option>
+                        <option value="2">2</option>
+                        <option value="3">3</option>
+                        <option value="4">4</option>
+                        <option value="5">5</option>
+                        <option value="6">6</option>
+                    </select>
+                    <label><input type="checkbox" id="idTaxBookSubmitted" checked> Salary tax book has been submitted to
+                        the employer</label>
+
+                    <label for="idExtraTaxDiscount" class="form-label text-bold">Extra tax-free amount:</label>
+                    <div class="input-group">
+                        <span class="input-group-text">€</span>
+                        <input type="number" class="form-control" id="idExtraTaxDiscount" placeholder="0" min="0"
+                               step="0.01">
+                    </div>
+
+                </div>
+                <div class="col col-md-5">
+                    <ul class="list-group">
+                        <li class="list-group-item d-flex justify-content-between align-items-start">
+                            <div class="ms-2 me-auto">
+                                <div class="fw-bold">Brutto salary</div>
+                            </div>
+                            <span id="idBruttoSalaryDisplay">1300,00€</span>
+                        </li>
+                        <li class="list-group-item d-flex justify-content-between align-items-start">
+                            <div class="ms-2 me-auto">
+                                <div class="fw-bold">Social security tax</div>
+                            </div>
+                            <span id="idSocialSecurityTaxDisplay" class="text-danger">969,26€</span>
+                        </li>
+                        <li class="list-group-item d-flex justify-content-between align-items-start">
+                            <div class="ms-2 me-auto">
+                                <div class="fw-bold">Income tax</div>
+                            </div>
+                            <span id="idIncomeTaxDisplay" class="text-danger">969,26€</span>
+                        </li>
+                        <li class="list-group-item d-flex justify-content-between align-items-start">
+                            <div class="ms-2 me-auto">
+                                <div class="fw-bold">Net salary</div>
+                            </div>
+                            <span id="idNetSalaryDisplay" class="text-primary">969,26€</span>
+                        </li>
+                        <li class="list-group-item d-flex justify-content-between align-items-start">
+                            <div class="ms-2 me-auto">
+                                <div class="fw-bold">Employer tax</div>
+                            </div>
+                            <span id="idEmployerTaxDisplay" class="text-warning">306.67€</span>
+                        </li>
+                        <li class="list-group-item d-flex justify-content-between align-items-start">
+                            <div class="ms-2 me-auto">
+                                <div class="fw-bold">Employer total cost</div>
+                            </div>
+                            <span id="idEmployerTotalCostDisplay">1606,67€</span>
+                        </li>
+                    </ul>
+                </div>
+            </form>
+
+        </div>
+    </div>
+</div>
+<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.2.3/dist/js/bootstrap.bundle.min.js"
+        integrity="sha384-kenU1KFdBIe4zVF0s0G1M5b4hcpxyD9F7jL+jjXkk+Q2h455rYXK/7HAuoJl+0I4"
+        crossorigin="anonymous"></script>
+<script>
+    // document.addEventListener("load", _ => {
+    const yearlySalaryLimit_1 = 20004,
+        yearlySalaryLimit_2 = 78100,
+        minTaxable = 500,
+        maxTaxable = 1800,
+        diffTaxable = minTaxable - maxTaxable,
+        minTaxFree = 0,
+        maxTaxFree = 500,
+        diffTaxFree = minTaxFree - maxTaxFree,
+        dependentsDiscount = 250,
+        halfPercent = 5 / 1000,
+        socialInsurancePercent = 105 / 1000;
+    const bruttoInput = document.getElementById("idBruttoInput"),
+        dependentInput = document.getElementById("idDependentsInput"),
+        taxBookSubmittedInput = document.getElementById("idTaxBookSubmitted"),
+        extraTaxDiscountInput = document.getElementById("idExtraTaxDiscount");
+    const displayEuro = amount => `${parseFloat(amount).toFixed(2)} €`.replace(".", ",")
+    const updateCalculatedNetSalary = _ => {
+        const bruttoSalary = parseFloat(bruttoInput.value),
+            dependentCount = parseInt(dependentInput.value),
+            taxDiscount = parseFloat(extraTaxDiscountInput.value),
+            taxBookSubmitted = !!taxBookSubmittedInput.checked,
+            socialSecurityTax = calculateSocialInsuranceAmount(bruttoSalary),
+            incomeTax = calculateIncomeTax(bruttoSalary, socialSecurityTax, taxDiscount, dependentCount, taxBookSubmitted),
+            netSalary = calculateNetSalary(bruttoSalary, socialSecurityTax, incomeTax),
+            employersSocialTax = calculateEmployersSocialInsuranceAmount(bruttoSalary),
+            employersTotalCost = bruttoSalary + employersSocialTax,
+            bruttoDisplay = document.getElementById("idBruttoSalaryDisplay"),
+            socialSecurityDisplay = document.getElementById("idSocialSecurityTaxDisplay"),
+            incomeTaxDisplay = document.getElementById("idIncomeTaxDisplay"),
+            netSalaryDisplay = document.getElementById("idNetSalaryDisplay"),
+            employerTaxDisplay = document.getElementById("idEmployerTaxDisplay"),
+            employerTotalCostDisplay = document.getElementById("idEmployerTotalCostDisplay");
+        bruttoDisplay.textContent = displayEuro(bruttoSalary);
+        socialSecurityDisplay.textContent = displayEuro(socialSecurityTax);
+        incomeTaxDisplay.textContent = displayEuro(incomeTax);
+        netSalaryDisplay.textContent = displayEuro(netSalary);
+        employerTaxDisplay.textContent = displayEuro(employersSocialTax);
+        employerTotalCostDisplay.textContent = displayEuro(employersTotalCost);
+    }
+    const calculateSocialInsuranceAmount = (bruttoSalary) => {
+        if (isNaN(bruttoSalary))
+            return 0.00;
+        return Math.min(bruttoSalary * socialInsurancePercent, yearlySalaryLimit_2 / 12 * (socialInsurancePercent - halfPercent) + (bruttoSalary * halfPercent))
+    }
+    const calculateIncomeTax = (bruttoSalary, socialInsuranceAmount, extraDiscount = 0, dependentCount = 0, taxBookSubmitted = true) => {
+        const taxRelief = taxBookSubmitted ? dependentCount * dependentsDiscount : 0,
+            actualTaxFreeAmount = (!taxBookSubmitted ? 0 : (bruttoSalary > maxTaxable ? minTaxFree : (bruttoSalary <= minTaxable ? maxTaxFree : (maxTaxFree - ((diffTaxFree / diffTaxable) * (bruttoSalary - minTaxable)))))),
+            incomeTaxBaseLow = Math.min(yearlySalaryLimit_1 / 12, bruttoSalary),
+            incomeTaxBaseMid = Math.max(Math.min(bruttoSalary - incomeTaxBaseLow, yearlySalaryLimit_2 / 12 - incomeTaxBaseLow), 0),
+            incomeTaxBaseTop = Math.max(bruttoSalary - incomeTaxBaseLow - incomeTaxBaseMid, 0),
+            incomeTaxLow = (incomeTaxBaseLow - socialInsuranceAmount - extraDiscount - actualTaxFreeAmount - taxRelief) * (20 / 100),
+            incomeTaxMid = incomeTaxBaseMid * (23 / 100),
+            incomeTaxTop = incomeTaxBaseTop * (31 / 100);
+        return Math.max(incomeTaxLow + incomeTaxMid + incomeTaxTop, 0)
+    }
+    const calculateNetSalary = (bruttoSalary, socialInsuranceAmount, incomeTax) => {
+        if (isNaN(bruttoSalary))
+            return 0.00;
+        return bruttoSalary - socialInsuranceAmount - incomeTax;
+    }
+    const calculateEmployersSocialInsuranceAmount = (bruttoSalary) => (bruttoSalary * 2359 / 10000)
+
+    bruttoInput.addEventListener("change", updateCalculatedNetSalary);
+    dependentInput.addEventListener("change", updateCalculatedNetSalary);
+    taxBookSubmittedInput.addEventListener("change", updateCalculatedNetSalary);
+    extraTaxDiscountInput.addEventListener("change", updateCalculatedNetSalary);
+
+    // })
+</script>
+</body>
+</html>
