#toolbox {
    position: absolute;
    z-index: 99;
    right: 0;
    width: 4em;
    text-align: center;
    padding: 2px 10px;

    #runButton[disabled], #runButton[disabled]:hover {
        background-color: #f2f2f2;
        color: #dedede;
    }

    .toolbox-button {
        float: right;
        margin-bottom: 0.313em;
        background-color: $brand-gray;
        padding: 0em;
        color: $black;
	    width: 40px;
	    height: 40px;
        font-size: 1.500em;
    }

    .toolbox-button:hover {
        background-color: $toolbox-btn-active;
    }

    .toolbox-button:focus {
        outline: none;
    }

    .box.is-dragover {
        background-color: grey;
    }
}

@mixin toolbox-button-base {
    background-color: $brand-gray;
    color: $black;
    padding: 0em;
    width: 40px;
    height: 40px;
    font-size: 1.500em;
}

@mixin toolbox-button-focus {
    outline: none;
}

@mixin toolbox-runButton-disabled {
    background-color: #f2f2f2;
    color: #dedede;
}

@mixin toolbox-runButton-hover {
    background-color: $toolbox-btn-active;
}

#toolbox {
    position: absolute;
    z-index: 99;
    right: 0;
    width: 4em;
    text-align: center;
    padding: 2px 10px;

    #runButton[disabled], #runButton[disabled]:hover {
        @include toolbox-runButton-disabled;
    }

    .toolbox-button {
        float: right;
        margin-bottom: 0.313em;
        @include toolbox-button-base;
    }

    .toolbox-button:hover {
        @include toolbox-runButton-hover;
    }

    .toolbox-button:focus {
        @include toolbox-button-focus;
    }

    .box.is-dragover {
        background-color: grey;
    }
}

Move rules to mixins for re-use in _panel.scss
Move rules to mixins for re-use in _panel.scss
