[SOLVED] Can you dynamically apply a colour scheme to a single css file?

Can you dynamically apply a colour scheme to a single css file?

I have 4 different css files that are identical except they use different colour schemes i.e. red, blue, green. At the start of my program a user chooses which colour scheme they want and then the corresponding css file is chosen. Is there a way to just have 1 css file and have all colour schemes located in that file then when a user chooses a scheme have each item in the css file have the chosen colour applied to them?

I am using javaFX 8.

Solution

As A Haworth mentioned, you can probably do something with CSS variables. I don't know how javaFX works, but hopefully you can do something similar to what I wrote below. I set a CSS variable to the body and then have jQuery change that variable when the user clicks the buttons.

$(document).ready(function() {
   $("body").on("click", "#blue", function() {
     $("body").css("--main-color", "blue");
   });
   $("body").on("click", "#red", function() {
     $("body").css("--main-color", "red");
   });
});

:body {
  --main-color: blue;
}

.div-1 {
  background: var(--main-color);
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <div class="div-1">Div 1</div>
  <button id='blue'>Blue</button>
  <button id='red'>Red</button>
</body>
</html>