javascript apply += to a css property code example
Example 1: javascript style an element
var myElement = document.querySelector("#myElement");
myElement.style.color = "blue";
myElement.style.backgroundColor = "red";
Example 2: javascript style
<element>.style.backgroundColor = '#000';
<element>.style.background = '#000';
<element>.style.color = '#fff';
<element>.style.boxSizing = 'border-box';
<element>.style.fontFamily = '\'Times New Roman\', Times, serif';
<element>.style.fontSize = '16px';
<element>.style.margin = 0;
<element>.style.padding = '20px';
<element>.style.width = '100%';
<element>.style.height = '100%';
<element>.style.marginLeft = 0;
<element>.style.fontWeight = 400;