sass use $variable into html style code example

Example 1: Sass Variables

$myFont: Helvetica, sans-serif;
$myColor: red;
$myFontSize: 18px;
$myWidth: 680px;

body {
  font-family: $myFont;
  font-size: $myFontSize;
  color: $myColor;
}

#container {
  width: $myWidth;
}

Example 2: how to make a scss variable

$variableName = item

$gray = #404040

body{
	background:$gray; 
}