body {
background-color: white;
font-family: ‘Inter’, -apple-system, BlinkMacSystemFont, sans-serif;
}
.gradient-bg {
background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}
.chart-container {
position: relative;
height: 300px;
margin: 20px 0;
}
.futuristic-border {
border: 2px solid transparent;
background: linear-gradient(white, white) padding-box, linear-gradient(45deg, #667eea, #764ba2) border-box;
border-radius: 15px;
}
.glow-effect {
box-shadow: 0 0 20px rgba(102, 126, 234, 0.3);
}
.feature-box {
background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
border-left: 4px solid #667eea;
}
@media (max-width: 768px) {
.chart-container {
height: 250px;
}
}

let pieChart, lineChart, userChart;

// Initialize charts on page load
window.addEventListener(‘load’, function() {
initializeCharts();
});

function initializeCharts() {
// Pie Chart – Sample TDEE Breakdown
const pieCtx = document.getElementById(‘pieChart’).getContext(‘2d’);
pieChart = new Chart(pieCtx, {
type: ‘pie’,
data: {
labels: [‘BMR’, ‘Exercise’, ‘Daily Activities’, ‘Thermic Effect’],
datasets: [{
data: [65, 20, 10, 5],
backgroundColor: [
‘#667eea’,
‘#764ba2’,
‘#f093fb’,
‘#f5576c’
],
borderWidth: 2,
borderColor: ‘#fff’
}]
},
options: {
responsive: true,
maintainAspectRatio: false,
plugins: {
legend: {
position: ‘bottom’,
labels: {
padding: 15,
usePointStyle: true
}
},
title: {
display: true,
text: ‘Typical Energy Expenditure Distribution’
}
}
}
});

// Line Chart – Activity Level Comparison
const lineCtx = document.getElementById(‘lineChart’).getContext(‘2d’);
lineChart = new Chart(lineCtx, {
type: ‘line’,
data: {
labels: [‘Sedentary’, ‘Light’, ‘Moderate’, ‘Very Active’, ‘Extremely Active’],
datasets: [{
label: ‘TDEE (calories)’,
data: [1800, 2063, 2325, 2588, 2850],
borderColor: ‘#667eea’,
backgroundColor: ‘rgba(102, 126, 234, 0.1)’,
borderWidth: 3,
fill: true,
tension: 0.4,
pointBackgroundColor: ‘#667eea’,
pointBorderColor: ‘#fff’,
pointBorderWidth: 2,
pointRadius: 6
}]
},
options: {
responsive: true,
maintainAspectRatio: false,
plugins: {
legend: {
display: false
}
},
scales: {
y: {
beginAtZero: false,
title: {
display: true,
text: ‘Calories per Day’
}
},
x: {
title: {
display: true,
text: ‘Activity Level’
}
}
}
}
});

// User Chart – Initially empty
const userCtx = document.getElementById(‘userChart’).getContext(‘2d’);
userChart = new Chart(userCtx, {
type: ‘bar’,
data: {
labels: [‘BMR’, ‘TDEE’, ‘Activity Calories’],
datasets: [{
label: ‘Calories’,
data: [0, 0, 0],
backgroundColor: [
‘rgba(102, 126, 234, 0.8)’,
‘rgba(34, 197, 94, 0.8)’,
‘rgba(168, 85, 247, 0.8)’
],
borderColor: [
‘#667eea’,
‘#22c55e’,
‘#a855f7’
],
borderWidth: 2
}]
},
options: {
responsive: true,
maintainAspectRatio: false,
plugins: {
legend: {
display: false
}
},
scales: {
y: {
beginAtZero: true,
title: {
display: true,
text: ‘Calories per Day’
}
}
}
}
});
}

function calculateTDEE() {
const gender = document.getElementById(‘gender’).value;
const age = parseFloat(document.getElementById(‘age’).value);
const weight = parseFloat(document.getElementById(‘weight’).value);
const height = parseFloat(document.getElementById(‘height’).value);
const activity = parseFloat(document.getElementById(‘activity’).value);

// Validation
if (!age || !weight || !height) {
alert(‘Please fill in all fields with valid numbers.’);
return;
}

if (age 120) {
alert(‘Please enter a valid age between 1 and 120 years.’);
return;
}

if (weight 500) {
alert(‘Please enter a valid weight between 1 and 500 kg.’);
return;
}

if (height 300) {
alert(‘Please enter a valid height between 1 and 300 cm.’);
return;
}

// Calculate BMR using Mifflin-St Jeor Equation
let bmr;
if (gender === ‘male’) {
bmr = 10 * weight + 6.25 * height – 5 * age + 5;
} else {
bmr = 10 * weight + 6.25 * height – 5 * age – 161;
}

// Calculate TDEE
const tdee = bmr * activity;
const activityCalories = tdee – bmr;

// Display results
document.getElementById(‘bmrResult’).textContent = Math.round(bmr);
document.getElementById(‘tdeeResult’).textContent = Math.round(tdee);
document.getElementById(‘activityCalories’).textContent = Math.round(activityCalories);
document.getElementById(‘results’).classList.remove(‘hidden’);

// Update user chart
userChart.data.datasets[0].data = [Math.round(bmr), Math.round(tdee), Math.round(activityCalories)];
userChart.update();

// Update line chart with user data
const activityLevels = [1.2, 1.375, 1.55, 1.725, 1.9];
const userTdeeData = activityLevels.map(level => Math.round(bmr * level));
lineChart.data.datasets[0].data = userTdeeData;
lineChart.update();

// Smooth scroll to results
document.getElementById(‘results’).scrollIntoView({ behavior: ‘smooth’ });
}

function resetCalculator() {
// Clear all input fields
document.getElementById(‘gender’).value = ‘male’;
document.getElementById(‘age’).value = ”;
document.getElementById(‘weight’).value = ”;
document.getElementById(‘height’).value = ”;
document.getElementById(‘activity’).value = ‘1.2’;

// Hide results
document.getElementById(‘results’).classList.add(‘hidden’);

// Reset user chart
userChart.data.datasets[0].data = [0, 0, 0];
userChart.update();

// Reset line chart to default data
lineChart.data.datasets[0].data = [1800, 2063, 2325, 2588, 2850];
lineChart.update();

// Scroll to top of calculator
document.querySelector(‘.bg-white.futuristic-border’).scrollIntoView({ behavior: ‘smooth’ });
}

// Add input event listeners for real-time validation
document.addEventListener(‘DOMContentLoaded’, function() {
const inputs = [‘age’, ‘weight’, ‘height’];
inputs.forEach(inputId => {
const input = document.getElementById(inputId);
input.addEventListener(‘input’, function() {
if (this.value < 0) {
this.value = '';
}
});
});
});