cursive.js

((text = '') => {
	const map = {
		a: '𝓪',
		A: '𝓐',
	};
	const shift = (char, shift) => String.fromCodePoint(char.codePointAt(0) + shift);
	Object.entries(map).forEach(([from, to]) => {
		for (let i = 0; i < 26; i++) {
			map[shift(from, i)] = shift(to, i);
		}
	});
	return text.split('').map(c => map[c] || c).join('') || map;
})(`ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz`);