@cd-z/epub-constructor/dist/src/methods/createStyle.js

This is a react library that creates an epub structure. This library only provides the file structure. To get a valid epub file it is needed to to create files from the provided data and compress them to a epub file.

/**
 * Generates a CSS string based on the provided style object.
 * If the style object is a string, it is returned as is.
 * The style object is merged with a default style object.
 *
 * @param style - The style object to generate CSS from.
 * @returns The CSS string representing the merged style object.
 */
export function createStyle(style) {
    if (typeof style === 'string') {
        return style;
    }
    if (!style) {
        return ('body {\n' +
            ' font-family: "Helvetica Neue", "Helvetica", "Arial", sans-serif;\n' +
            ' font-size: 1.125em;\n' +
            ' line-height: 1.6em;\n' +
            ' color: #000;\n' +
            '}\n' +
            'h1, h2, h3, h4, h5, h6 {\n' +
            ' line-height: 1em;\n' +
            '}\n' +
            'h1 {\n' +
            ' font-size: 3em;\n' +
            '}\n' +
            'h2 {\n' +
            ' font-size: 2.5em;\n' +
            '}\n');
    }
    // Creating well formated css
    var result = '';
    Object.keys(style).forEach(x => {
        const key = x;
        var item = x + ' {';
        Object.keys(style[key]).forEach(a => {
            item += `\n ${a}: ${style[key][a]};`;
        });
        item += '\n}\n';
        result += item;
    });
    return result;
}