How to make CSS style final? - html

Question

I need help on how to make CSS styles final so that they could not be overwritten by Javascript.
Problem: Sometimes, because of the img tag in the JavaScript code, everything, (all styles of all of the images) gets overwritten.
Here is my code:
<img src='logoImg' style='width:45px; height:30px;' >
Please tell me ways to do this in JavaScript or in CSS itself.
Desired output: I need the Logo Image to have final styling. So it is not affected by JavaScript through the DOM (document object model).

Answer 1

You can try adding !important keyword to your CSS properties to prevent them from getting changed.
Example
const test = document.getElementById("test");
// The color won't change to orange
// due to !important keyword in the CSS code
test.style.backgroundColor = "orange";
#test {
width: 50px;
height: 50px;
background: green !important;
}
<div id="test"></div>
Ideally though it would be better to work around this using a different solution like using a more specific method of selecting an HTML element and changing it's properties.
If you have some kind of a style applied by selecting a tag, you can override it by using a class or an id when it comes to CSS. If you're searching for elements in JavaScript code, you can look for them by a class name or an id value instead.
An alternative solution in your case would be to re-write/modify the JavaScript code that targets your img tags and either skip images that have a specific class like let's say logo, or make a custom class for all your standard images that do not include your logo element and look them up in your JavaScript code using document.getElementsByClassName method.

Answer 2

If you want to prevent JS to overwrite the style of an image, you need to style it in CSS and add important; to raise it specificty weight. !important has a higher specificty weight then inline-style and as such JS style (JS add the style as inline-style) wont apply.
function resize() {
document.querySelector("img").style.height = "200px";
document.querySelector("img").style.width = "200px";
}
img.test {
width: 45px !important;
height: 30px !important;
}
<img src='https://via.placeholder.com/200x200.jpg' class="test">
<button onclick="resize()">Test</button>