gistfile1.txt

const siteHeaderElement = .nativeElement;

const customClasses = localStorage.getItem('custom');


.brand-name{color: blue}
// regex to get array of classname
const classNames = ['NP1', 'NP2', 'LC'];

function getElement(className): ElementRef {
  return siteHeaderElement.find(className);
}

// array of elements inside the site header that have custom css
const elements = classNames.map(c => getElement(c));
// regex 
elements.forEach(e => e.style=doRegexGetStyle);

// second solution 

const styleTag = document.createElement("style") //localStorage;
styleTag.innerHTML = cssTemplateString ;
document.head.insertAdjacentElement('beforeend', styleTag);