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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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Adding Classes

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Insecure Resource

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CSS

About CSS Preprocessors

CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                <div id="graph-container">
        <svg id="graph" width="600" height="300"></svg>
        <div id="tooltip" class="tooltip"></div>
    </div>
!

CSS 

              
                        body {
            font-family: Arial, sans-serif;
            background-color: #f5f5f5;
        }

        #graph-container {
            width: 800px;
            margin: 50px auto;
            position: relative;
        }

        #graph {
            background-color: #fff;
            border: 1px solid #ddd;
        }

        .grid line {
            stroke: #e0e0e0;
            stroke-dasharray: 5,5;
        }

        .axis path,
        .axis line {
            stroke: #000;
        }

        .data-line {
            fill: none;
            stroke: #3498db;
            stroke-width: 2;
        }

        .data-area {
            fill: url(#gradient);
            opacity: 0.7;
        }

        .data-point {
            fill: #3498db;
            stroke: #fff;
            stroke-width: 2;
            cursor: pointer;
            transition: transform 0.2s;
        }

          .tooltip {
            position: absolute;
            background: rgba(0,0,0,0.7);
            color: #fff;
            padding: 6px 10px;
            border-radius: 4px;
            pointer-events: none;
            opacity: 0;
            transition: opacity 0.3s;
            font-size: 12px;
        }
!

JS 

              
                document.addEventListener("DOMContentLoaded", function() {
            const svg = document.getElementById("graph");
            const tooltip = document.getElementById("tooltip");
            const width = svg.clientWidth;
            const height = svg.clientHeight;
            const padding = { top: 50, right: 50, bottom: 50, left: 50 };

            // Sample Data: Replace this with your actual data
            const data = [
                { month: "January", value: 30 },
                { month: "February", value: 45 },
                { month: "March", value: 20 },
                { month: "April", value: 60 },
                { month: "May", value: 50 },
                { month: "June", value: 70 },
                { month: "July", value: 80 },
                { month: "August", value: 55 },
                { month: "September", value: 65 },
                { month: "October", value: 40 },
                { month: "November", value: 35 },
                { month: "December", value: 50 },
            ];

            // Determine the maximum value for scaling
            const maxValue = Math.max(...data.map(d => d.value));

            // Scales for X and Y axes
            const xScale = (index) => padding.left + (index * (width - padding.left - padding.right)) / (data.length - 1);
            const yScale = (value) => padding.top + ((maxValue - value) * (height - padding.top - padding.bottom)) / maxValue;

            // Create Grid Lines
            const numRows = 5; // Number of horizontal grid lines
            const gridGroup = document.createElementNS("http://www.w3.org/2000/svg", "g");
            gridGroup.setAttribute("class", "grid");
            for (let i = 0; i <= numRows; i++) {
                const y = padding.top + i * (height - padding.top - padding.bottom) / numRows;
                const line = document.createElementNS("http://www.w3.org/2000/svg", "line");
                line.setAttribute("x1", padding.left);
                line.setAttribute("y1", y);
                line.setAttribute("x2", width - padding.right);
                line.setAttribute("y2", y);
                gridGroup.appendChild(line);
            }
            svg.appendChild(gridGroup);

            // Create Axes
            const axisGroup = document.createElementNS("http://www.w3.org/2000/svg", "g");
            axisGroup.setAttribute("class", "axis");

            // Y Axis
            const yAxis = document.createElementNS("http://www.w3.org/2000/svg", "line");
            yAxis.setAttribute("x1", padding.left);
            yAxis.setAttribute("y1", padding.top);
            yAxis.setAttribute("x2", padding.left);
            yAxis.setAttribute("y2", height - padding.bottom);
            axisGroup.appendChild(yAxis);

            // X Axis
            const xAxis = document.createElementNS("http://www.w3.org/2000/svg", "line");
            xAxis.setAttribute("x1", padding.left);
            xAxis.setAttribute("y1", height - padding.bottom);
            xAxis.setAttribute("x2", width - padding.right);
            xAxis.setAttribute("y2", height - padding.bottom);
            axisGroup.appendChild(xAxis);

            // Y Axis Labels
            for (let i = 0; i <= numRows; i++) {
                const value = Math.round(maxValue - (i * maxValue) / numRows);
                const y = padding.top + i * (height - padding.top - padding.bottom) / numRows;
                const text = document.createElementNS("http://www.w3.org/2000/svg", "text");
                text.setAttribute("x", padding.left - 10);
                text.setAttribute("y", y + 5);
                text.setAttribute("text-anchor", "end");
                text.setAttribute("font-size", "12");
                text.textContent = value;
                axisGroup.appendChild(text);
            }

            // X Axis Labels (Months)
            data.forEach((d, index) => {
                const x = xScale(index);
                const y = height - padding.bottom + 20;
                const text = document.createElementNS("http://www.w3.org/2000/svg", "text");
                text.setAttribute("x", x);
                text.setAttribute("y", y);
                text.setAttribute("text-anchor", "middle");
                text.setAttribute("font-size", "12");
                text.textContent = d.month.substring(0, 3); // Short month name
                axisGroup.appendChild(text);
            });

            svg.appendChild(axisGroup);

            // Define Gradient for Data Area
            const defs = document.createElementNS("http://www.w3.org/2000/svg", "defs");
            const gradient = document.createElementNS("http://www.w3.org/2000/svg", "linearGradient");
            gradient.setAttribute("id", "gradient");
            gradient.setAttribute("x1", "0%");
            gradient.setAttribute("y1", "0%");
            gradient.setAttribute("x2", "0%");
            gradient.setAttribute("y2", "100%");
            const stop1 = document.createElementNS("http://www.w3.org/2000/svg", "stop");
            stop1.setAttribute("offset", "0%");
            stop1.setAttribute("stop-color", "#3498db");
            stop1.setAttribute("stop-opacity", "0.7");
            const stop2 = document.createElementNS("http://www.w3.org/2000/svg", "stop");
            stop2.setAttribute("offset", "100%");
            stop2.setAttribute("stop-color", "#3498db");
            stop2.setAttribute("stop-opacity", "0");
            gradient.appendChild(stop1);
            gradient.appendChild(stop2);
            defs.appendChild(gradient);
            svg.appendChild(defs);

            // Create Data Area (Under the Line)
            const areaPath = document.createElementNS("http://www.w3.org/2000/svg", "path");
            let areaData = "M";
            data.forEach((d, index) => {
                const x = xScale(index);
                const y = yScale(d.value);
                areaData += `${x} ${y} `;
            });

            // Close the path to create the filled area
            areaData += `L ${xScale(data.length - 1)} ${height - padding.bottom} L ${xScale(0)} ${height - padding.bottom} Z`;
            areaPath.setAttribute("d", areaData);
            areaPath.setAttribute("class", "data-area");
            svg.appendChild(areaPath);

            // Create Data Line
            const linePath = document.createElementNS("http://www.w3.org/2000/svg", "path");
            let pathData = "";
            data.forEach((d, index) => {
                const x = xScale(index);
                const y = yScale(d.value);
                pathData += `${index === 0 ? 'M' : 'L'} ${x} ${y} `;
            });
            linePath.setAttribute("d", pathData);
            linePath.setAttribute("class", "data-line");
            svg.appendChild(linePath);

            // Create Data Points
            data.forEach((d, index) => {
                const x = xScale(index);
                const y = yScale(d.value);
                const circle = document.createElementNS("http://www.w3.org/2000/svg", "circle");
                circle.setAttribute("cx", x);
                circle.setAttribute("cy", y);
                circle.setAttribute("r", 5);
                circle.setAttribute("class", "data-point");
                
                // Tooltip Interactivity
                circle.addEventListener("mouseover", () => {
                    tooltip.style.opacity = 1;
                    tooltip.textContent = `${d.month}: ${d.value}`;
                });
                circle.addEventListener("mousemove", (event) => {
                    const rect = document.getElementById("graph-container").getBoundingClientRect();
                    tooltip.style.left = (event.clientX - rect.left + 10) + "px";
                    tooltip.style.top = (event.clientY - rect.top - 25) + "px";
                });
                circle.addEventListener("mouseout", () => {
                    tooltip.style.opacity = 0;
                });

                svg.appendChild(circle);
            });

        });
!
999px

Console