Improve CSSStyleDeclaration typings

Not every string should be allowed in properties of the CSSStyleDeclaration interface, such as display, overflow, etc. The TypeStyle project seems to have put quite some effort into this already, from which inspiration could be taken.

[edmundmaruhn]

Just a question: Why is the index type of CSSStyleDeclaration’s index signature number and not string?

In case you want to apply a list of styles to HTMLElement.style one (like me) could try:

let element: HTMLElement = window.document.create('div');
let styles: { [key: string]: string } = {
    display: 'inline-block',
    width: '36px',
    height: '36px'
};

for (let style in styles) {
    element.style[style] = styles[style]; // generates TS7015, because index type is not 'number'
}

My current workaround is a cast to any:

(<any>element.style)[style] = styles[style];

which is really ugly.

[HolgerJeromin]

@GlenPerkins Just use: mydiv.style.setProperty('font-size', '24px') and mydiv.style.getPropertyValue('font-size')