I'm making a style guide with some color blocks. The HTML looks like this: 

```
<div class="colorBlock _fafafa">Light Gray (#fafafa)</div>  
<div class="colorBlock _eaeaea">Gray (#eaeaea)</div>  
<div class="colorBlock _777">Meta-Gray (#777)</div>  
<div class="colorBlock _555">Gray 5 (#555)</div>  
<div class="colorBlock _444">Gray 4 (#444)</div>  
<div class="colorBlock _333">Gray 3 (#333)</div>  

```

And I'd like to write some DRY-principle SASS that compiles to this CSS: 

```
.colorBlock._fafafa { 
    background-color: #fafafa; 
} 
.colorBlock._eaeaea { 
    background-color: #eaeaea; 
} 
...

```

So I'm trying out lists and `@each`. Here's what I've tried: 

```
$colors: fafafa eaeaea 777 555 444; 

.colorBlock { 
    @each $color in $colors { 
        &._#{$color} { 
            background-color: ##{$color}; 
        } 
    } 
}

```

Which would work, but Sass doesn't like `##{$color}` and fails upon compilation. I tried `\##{$color}`, which successfully compiles, but prints `\#fafafa`. I also tried `#$color`, but that also fails on compilation (`Invalid CSS after "...kground-color: ": expected expression (e.g. 1px, bold), was "#$color; "`). I also tried `#{# + $color}` and other similar combinations. What's the right way to do this?