.tab {
    display: none;
}
.active {
    display: block;
}

.header {
    margin-bottom: 10px;
    /*border-bottom: 1px solid #ccc;*/
    font-size: 0;
}
.header:after{
    content: '';
    display: block;
    height: 0;
    border-bottom: 1px solid #ccc;
    margin-top: -5px;
}
.button {
    display: inline-block;
    padding: 5px 10px;
    text-decoration: none;
    background-color: #efefef;
    color: #464646;
    margin-right:  5px;
    height: 23px;
    cursor: pointer;
    font-size: 12px;
    line-height: 14px;
    opacity: .7;
    user-select: none;
    vertical-align: top;
    margin-bottom: 5px;
}
.buttonActive {
    position: relative;
    bottom: -1px;
    background-color: #5f5f5f;
    color: #fff;
    opacity: 1;
}