YouTube Rainbow Theme Switcher

Movable GUI to switch YouTube rainbow themes (Red, Orange, Yellow, Green, Blue, Purple, Pink, White, Black)

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(I already have a user script manager, let me install it!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name         YouTube Rainbow Theme Switcher
// @namespace    https://youtube.com/
// @version      1.0
// @description  Movable GUI to switch YouTube rainbow themes (Red, Orange, Yellow, Green, Blue, Purple, Pink, White, Black)
// @author       sonic
// @match        *://*.youtube.com/*
// @icon         https://www.youtube.com/s/desktop/fe2fda87/img/favicon.ico
// @grant        GM_addStyle
// ==/UserScript==

(function() {
    'use strict';

    const themes = {
        "Red": `
            html { --yt-spec-general-background-a: #330000 !important; --yt-spec-general-background-b: #440000 !important; --yt-spec-text-primary: #ffcccc !important; }
        `,
        "Orange": `
            html { --yt-spec-general-background-a: #331a00 !important; --yt-spec-general-background-b: #442200 !important; --yt-spec-text-primary: #ffe6cc !important; }
        `,
        "Yellow": `
            html { --yt-spec-general-background-a: #333300 !important; --yt-spec-general-background-b: #4d4d00 !important; --yt-spec-text-primary: #ffffcc !important; }
        `,
        "Green": `
            html { --yt-spec-general-background-a: #001a00 !important; --yt-spec-general-background-b: #003300 !important; --yt-spec-text-primary: #ccffcc !important; }
        `,
        "Blue": `
            html { --yt-spec-general-background-a: #00001a !important; --yt-spec-general-background-b: #000033 !important; --yt-spec-text-primary: #cce6ff !important; }
        `,
        "Purple": `
            html { --yt-spec-general-background-a: #1a001a !important; --yt-spec-general-background-b: #330033 !important; --yt-spec-text-primary: #f0ccff !important; }
        `,
        "Pink": `
            html { --yt-spec-general-background-a: #1a0010 !important; --yt-spec-general-background-b: #33001a !important; --yt-spec-text-primary: #ffd6e6 !important; }
        `,
        "White": `
            html { --yt-spec-general-background-a: #e6e6e6 !important; --yt-spec-general-background-b: #f2f2f2 !important; --yt-spec-text-primary: #000 !important; }
        `,
        "Black": `
            html { --yt-spec-general-background-a: #000 !important; --yt-spec-general-background-b: #111 !important; --yt-spec-text-primary: #fff !important; }
        `
    };

    const styleEl = document.createElement("style");
    document.head.appendChild(styleEl);

    function applyTheme(themeName) {
        if (!themes[themeName]) return;
        styleEl.innerHTML = themes[themeName];
        localStorage.setItem("ytRainbowTheme", themeName);
    }

    // Load saved theme
    const saved = localStorage.getItem("ytRainbowTheme") || "Red";
    applyTheme(saved);

    // Create GUI
    const gui = document.createElement("div");
    gui.id = "yt-theme-switcher";
    gui.innerHTML = `<b>🎨 Themes</b><br>` + 
        Object.keys(themes).map(t => `<button data-theme="${t}">${t}</button>`).join(" ");
    document.body.appendChild(gui);

    GM_addStyle(`
        #yt-theme-switcher {
            position: fixed;
            top: 100px;
            left: 20px;
            background: rgba(0,0,0,0.8);
            color: white;
            padding: 10px;
            border-radius: 8px;
            z-index: 999999;
            font-size: 14px;
            user-select: none;
            cursor: move;
        }
        #yt-theme-switcher button {
            margin: 2px;
            padding: 5px 8px;
            background: #333;
            color: white;
            border: 1px solid #555;
            border-radius: 4px;
            cursor: pointer;
        }
        #yt-theme-switcher button:hover {
            background: #555;
        }
        @media (max-width: 600px) {
            #yt-theme-switcher {
                top: 60px;
                left: 10px;
                font-size: 12px;
                padding: 6px;
            }
            #yt-theme-switcher button {
                padding: 3px 5px;
                font-size: 12px;
            }
        }
    `);

    // Draggable GUI
    let isDragging = false, offsetX, offsetY;
    gui.addEventListener("mousedown", e => {
        isDragging = true;
        offsetX = e.clientX - gui.offsetLeft;
        offsetY = e.clientY - gui.offsetTop;
    });
    document.addEventListener("mousemove", e => {
        if (isDragging) {
            gui.style.left = (e.clientX - offsetX) + "px";
            gui.style.top = (e.clientY - offsetY) + "px";
        }
    });
    document.addEventListener("mouseup", () => isDragging = false);

    // Theme button click
    gui.querySelectorAll("button").forEach(btn => {
        btn.addEventListener("click", () => applyTheme(btn.dataset.theme));
    });
})();