.example_block {
    padding: 15px; 

    &.fullheight {height: 100%;}
    
    &.blue {background-color: lightblue;}
    &.green {background-color: lightgreen;}
    &.yellow {background-color: lightyellow;}
    &.red {background-color: red;}
    
    &.bluedark {background-color: blue; width: 150px;}
    &.greendark {background-color: green; width: 50px;}
    &.yellowdark {background-color: yellow; width: 200px;}
}