keyboard.css

span {
    display: inline-block;
    width: 56px;
    height: 48px;
    border: solid 1px rgba(126, 126, 126, 0.59);
    margin: 4px;
    text-align: center;
    line-height: 46px;
    font-family: sans-serif;
    font-weight: bold;
    font-size: 130%;
    color: darkslategray;
    vertical-align: top;
    border-radius: 5px;
    transition: all ease 1s;
}

dir#keyboard {
    width: 960px;
    margin: 90px auto;
    padding: 0;
    position: relative;
}

div#background {
    position: absolute;
    top: 0px;
    opacity: 0.7;
    width: 960px;
    z-index: -1;
}

.active {
    background-color: hsla(39, 100%, 52%, 0.75);
    color: white;
}

.option, .shift {
}

#background > div {
    height: 56px;
}

#background > div:nth-child(1) > span {
    float: right;
    width: 120px;
}

#keyboard > div:nth-child(2) > span:nth-child(13) {
    width: 97px;
}

#keyboard > div:nth-child(2) {
    padding-left: 87px;
}

#background > div:nth-child(2) > span {
    width: 79px;
    text-align: left;
    padding-left: 10px;
}

* {
    box-sizing: border-box;
}

#background > div > span {
    font-size: 86%;
}

#background > div:nth-child(3) > span:nth-child(1) {
    width: 94px;
    word-break: break-word;
    padding-right: 38px;
    line-height: 16px;
    padding-top: 7px;
}

#keyboard > div:nth-child(3) {
    padding-left: 102px;
}

#background > div:nth-child(3) > span:nth-child(2) {
    float: right;
    width: 146px;
}

#background > div:nth-child(4) > span:nth-child(1) {
    width: 110px;
}

#keyboard > div:nth-child(4) {
    padding-left: 118px;
}

#background > div:nth-child(4) > span:nth-child(2) {
    float: right;
    width: 193px;
}

#background > div:nth-child(5) > span {
    font-size: 70%;
}

#background > div:nth-child(5) > span:nth-child(4) {
    width: 80px;
}

#background > div:nth-child(5) > span:nth-child(6) {
    width: 80px;
}

#background > div:nth-child(5) > span:nth-child(5) {
    width: 392px;
}