Prefered Coding Standard: SASS + Bourbon Neat

standards.scss

.class-name {
    // styles for the parent class first.
    font-size:20px;
    margin-left:15px;
    padding:20px 5px;
    font-family: 'Lato', sans-serif;
    background-color:#333;
    
    // styles for html elements before any child classes.
    ul {
        list-style:none;
        margin:0;
        padding:0;
        
        li {
            float:left;
            a {
                text-decoration:none;
                color:#eee
                &:hover {
                    color:#e3e3e3;
                }
            }
        }
    }
    
    // child classes come after html elements
    // if you are using includes, they will always go at the 
    // bottom of the class structure. In this case, we will
    // be using Bourbon Neat (http://neat.bourbon.io)
    .awesome-class {
        background-color:red;
        color:#fff;
        margin-top:20px;
        padding:0px 20px;
        
        // html elements
        a {
            color:#6600CC;
            &:hover {
                color:#000;    
            }
        }
        
        // child classes.
        .awesome-sub {
            display:none;
            padding:20px;
            border:2px solid #333;
        }
        
        // Includes, Mixins, Etc...
        @include span-columns(12);
        @include media($tablet){
            padding:10px;
            
            @include span-columns(6);    
        }
    }

}