To ensure that your JavaScript code runs after the DOM has fully loaded, you can use the built-in DOMContentLoaded event. This event is fired when the initial HTML document has been completely loaded and parsed, without waiting for stylesheets, images, and subframes to finish loading. Here’s how you can implement it:

document.addEventListener("DOMContentLoaded", function() {
    // Your code goes here
    console.log("DOM fully loaded and parsed");
});

Alternatively, if you want to ensure that the entire page, including all dependent resources like images, is fully loaded before executing your code, you can use the load event on the window object. This is how it looks:

window.addEventListener("load", function() {
    // Your code goes here
    console.log("Page fully loaded");
});

Using either of these methods will allow you to effectively run your script at the right time, ensuring that all elements are available for manipulation.