クリック毎に暗色変化
<script language="JavaScript">
<!--
function anshoku(){


var blue = Math.random()
var blue_b = blue * 64
var blue_c = Math.ceil(blue_b);
var blue_e = blue_c ;


var green = Math.random()
var green_b = green * 64;
var green_c = Math.ceil(green_b);
var green_e = green_c * 256;


var red = Math.random()
var red_b = red * 64
var red_c = Math.ceil(red_b);
var red_e = red_c * 65536 ;



var d = red_e + green_e + blue_e;

document.bgColor = d ;

}

//-->
</script>
</head>

<body>

<script language="JavaScript">
<!--
anshoku();
//-->
</script>