.opt1 {
    background-color: #f4511e;
    height: 100%;
    max-height: 100%;
    transition: 1s;
}

.opt1:hover {
    background-color: #ff8a65;
}

.opt2 {
    background-color: #039be5 ;
    height: 100%;
    max-height: 100%;
    transition: 1s;
}

.opt2:hover {
    background-color: #4fc3f7;
}

.r1 {
    height: 100%;
    max-height: 100%;
    margin-top: 100%;
}

.r2 {
    height: 100%;
    max-height: 100%;
    background-color: forestgreen;
    display: none;
    margin-top: 50%;
}

html, body {
    height: 100%;
    margin: 0;
    max-height: 100%;
    overflow: hidden;
    background-color: #161616;
  }

.ico {
    color: white;
    font-size: 50vmin;
    -ms-transform: translateY(50%);
    transform: translateY(50%);
}

.collection .collection-item.active {
    /* background-color: #00c853; */

}