style.css

* {
    margin: 0;
    padding: 0;
}

body {
    background: #000;
    overflow: hidden;
}

.selections {
    margin: -10px auto -10px auto;
    position: relative;
    display: flex;
    transition: all .5s ease;
    height: 100px;
    align-items: center;

}


.blend {
    display: inline-block;
    justify-content: center;
    align-items: center;
    margin: 0 auto;
    backface-visibility: hidden;
}

.corner {
    display: inline-block;
    justify-content: center;
    align-items: center;
    margin: 0 auto;
    backface-visibility: hidden;
}

.erase {
    display: inline-block;
    justify-content: center;
    align-items: center;
    margin: 0 auto;
    backface-visibility: hidden;
}

select {
    width: 200px;
    padding: 5px;
    margin: 15px;
    color: white;
    outline: none;
    background: rgba(255, 255, 255, .25);
    backface-visibility: hidden;
}

option {
    width: 200px;
    padding: 5px;
    margin: 15px;
    color: white;
    background: rgba(0, 0, 0, .75);
}

button {
    width: 150px;
    height: 30px;
    padding: 5px;
    margin: 15px;
    color: white;
    border: none;
    background: rgba(255, 255, 255, .25);
    outline: none;
    backface-visibility: hidden;

}

button:hover {
    background: rgba(255, 255, 255, .6);
    cursor: pointer;
}

button:active {
    background: rgba(255, 255, 255, .6);
    cursor: pointer;
    animation: moveUpDown .1s ease;
}

@keyframes moveUpDown {
    50% {
        transform: translateY(4px);
    }

}