This is a plugin for TiddlyWiki Classic. A macro switchPalette is introduced for the user to switch color palettes with ease.
You can install the plugin by just creating a new tiddler named SwitchPalettePlugin with the content copied from SwitchPalettePlugin.js and adding the systemConfig tag to the tiddler. Remember to reload the TiddlyWiki before you can use it.
Also check here for a live demo with several color palettes enclosed: SwitchPalettePlugin on github.io.
This work was inspired by Yakov Litvin's DarkModePlugin.