#keyInput{
    width: calc(100% - 43px);
    float: left;
}

.addkey{
    height: 38px;
    line-height: 38px;
    width: 38px;
    text-align: center;
    border: 1px solid #eee;
    float: right;
}

.night .addkey{
    border: 1px solid #444;
    color: #aaa;
}