Last Friday

You said

Use pure JavaScript code that creates a <main> element at the center of the visible screen. The <main> element always stays over other elements and occupies 1/4 area of the visible screen. The <main> element is scrollable because elements are dynamically appended to it.

Copilot said

Here’s a solution in pure JavaScript that satisfies your requirements:

javascript
// Create the <main> element
const mainElement = document.createElement('main');

// Apply styles to the <main> element
Object.assign(mainElement.style, {
    position: 'fixed', // Stay over other elements
    top: '50%',
    left: '50%',
    transform: 'translate(-50%, -50%)', // Center in the viewport
    width: '25vw', // 1/4 of the visible screen width
    height: '25vh', // 1/4 of the visible screen height
    backgroundColor: 'rgba(255, 255, 255, 0.9)', // Light background for visibility
    boxShadow: '0 4px 8px rgba(0, 0, 0, 0.2)', // Subtle shadow for better aesthetics
    overflowY: 'auto', // Make it scrollable
    zIndex: '1000', // Ensure it's on top
    borderRadius: '8px', // Add rounded corners for style
    padding: '10px', // Space inside the <main> element
    boxSizing: 'border-box'
});

// Append the <main> element to the body
document.body.appendChild(mainElement);

// Dynamically append content to the <main> element
function appendContent() {
    const newElement = document.createElement('p');
    newElement.textContent = `Dynamic content added at ${new Date().toLocaleTimeString()}`;
    mainElement.appendChild(newElement);
}

// Add some content initially
for (let i = 0; i < 5; i++) {
    appendContent();
}

// Example: Append content every 2 seconds
setInterval(appendContent, 2000);

Explanation:

  1. CSS Styling: The <main> element is styled using position: fixed, transform, and top/left values to center it and make it stay visible over other elements.

  2. Dynamic Content: The appendContent function demonstrates how elements can be added dynamically into the <main> element.

  3. Scrollability: The overflowY: auto ensures the <main> element becomes scrollable when content overflows.

Feel free to tweak the styles or behavior as needed to fit your project! Let me know if you'd like further modifications or explanations.