need help with showing css bars

If I would like to have the bar to have diffrent colors, how can this be done?

I have tried the following

css file

.graph { 
        position: relative;
        width: 200px; 
        border: 1px solid #B1D632; 
        padding: 2px; 
    }
	.bar_low{
	background: ##ff0000;
	}
	.bar_lowMid{
	background: ##ffb700; 
	}
	.bar_mid{
	background: ##fff700;
	}
	.bar_midHigh{
	background: ##aeff00;
	}
	.bar_high{
	background: ##0eff00; 
	}
    .graph .bar_low .bar_lowMid .bar_mid .bar_midHigh .bar_high { 
        display: block;
        position: relative;
        text-align: center; 
        color: #333; 
        height: 2em; 
        line-height: 2em;            
    }
    .graph .bar_low .bar_lowMid .bar_mid .bar_midHigh .bar_high span { position: absolute; left: 1em; }

Code (markup):

and in html

<div class="graph">
<strong class="bar_mid" style="width: 75%;">50/100</strong></div>

Code (markup):

Why don't the bar show for example bar_mid, only the graph shows?

Thanks

 

Remove the second hash from the colors.

 

Always mention float, height and width, then try it with background-color