Change background transparency of a button css javascript

Question

I'm new here and I have a question that might be simple but I just couldn't find an answer after googling for a while.

I have some buttons in my browser game that are green with a white text. When I hover over them, I change the rgba with CSS and the green becomes more transparent:

#oneOfTheButtons:hover {
  background: rgba(76, 175, 80, 0.7) !important;
}

The white text stays the same. I also have some Javascript that changes the color if the player goes level up:

document.getElementById("oneOfTheButtons").style.background = "rgba(77, 173, 173, 1)";

Then the buttons are blue. But the problem is that a hover still makes them transparent green, but I want them to be a transparent blue. I have 20 more levels like that with different colors.

Is there any simple solution for this?

Answer 1

This could be done in many different ways, but you could do it with css variables like this:

 let green = true; function toggleColor() { if (green) { document.body.style.setProperty('--button-bg-color', '77, 173, 173'); } else { document.body.style.setProperty('--button-bg-color', '76, 175, 80'); } green = !green; } 

 :root { --button-bg-color: 76, 175, 80; } button { background: rgba(var(--button-bg-color), 1); } button:hover { background: rgba(var(--button-bg-color), 0.7); } 

 <button onclick="toggleColor()">Toggle hover color!</button> 

Answer 2

You could use the following css

.green:hover {
  background: rgba(76, 175, 80, 0.7);
}
.green {
  background: rgba(76, 175, 80, 1);
}
.blue {
  background: rgba(77, 173, 173, 1);
}
.blue:hover {
  background: rgba(77, 173, 173, 0.7);
}

And the following js

document.getElementById("oneOfTheButtons").className = "blue";