body {font-family: Arial, Helvetica, sans-serif;}
 table{border-collapse:collapse;} td{padding:5px;}
 table,th,td{border: 1px solid black;}

/* https://www.w3schools.com/html/html_css.asp
 0. Browser default
 1. *.css files (with no HTML tags ! ) linked in header:
    <link rel="stylesheet" type="text/css" href="styles.css">
 2. In header style:  <style> declarations </style>
 3. In body (inline): <h1 style="declaration;">Header Text</h1>
 The last read applicable command rules.

 COMMANDS: selectors {declarations}
 DECLARATIONS: property:value; property:value; 
 SELECTORS: element.class, .class, element, #id
 (E.G.: CLASS(ES) IN ELEMENTS: <p class="center large">)

 OPACITY: rgba(red, green, blue, alpha)
 HUE/SATURATION/LIGHTNESS/ALPHA E.G.:  hsl(360, 100%, 100%, 1)

 COLOR IMAGE REPEAT ATTACHMENT POSITION:
 background: #ffffff url("img_tree.png") no-repeat right top;
 WIDTH STYLE(REQUIRED) COLOR: border: 5px solid red; border-radius: 5px;

 */