h1 {text-align: center;}
h2 {text-align: center;}
h3 {
    text-align: center;}
h4 {
    text-align: center;
    padding-top: 50px;
}
div.bg {
    background-color: #EBEBFF; 
}
div.sheet-tab-content { display: none; }

input.sheet-tab1:checked ~ div.sheet-tab1,
input.sheet-tab2:checked ~ div.sheet-tab2,
input.sheet-tab3:checked ~ div.sheet-tab3,
input.sheet-tab4:checked ~ div.sheet-tab4,
input.sheet-tab5:checked ~ div.sheet-tab5,
input.sheet-tab6:checked ~ div.sheet-tab6,
{
    display: block;
}

input.sheet-tab
{
    width: 33%;
    height: 20px;
    position: relative;
    top: 5px;
    left: 6px;
    margin: -1.5px;
    cursor: pointer;
    z-index: 1;
}

input.sheet-tab::before
{
    content: attr(title);

    border: solid 1px #a8a8a8;
    border-bottom-color: black;
    text-align: center;
    display: inline-block;
    
    background: #fff;
    background: -moz-linear-gradient(to top, #c8c8c8, #fff, #c8c8c8);
    background: -webkit-linear-gradient(to top, #c8c8c8, #fff, #c8c8c8);
    background: -ms-linear-gradient(to top, #c8c8c8, #fff, #c8c8c8);
    background: -o-linear-gradient(to top, #c8c8c8, #fff, #c8c8c8);
    background: linear-gradient(to top, #c8c8c8, #fff, #c8c8c8);
    width: 100%;
    height: 20px;
    font-size: 18px;
}

input.sheet-tab:checked::before
{
    background: #dcdcdc;
    background: -moz-linear-gradient(to top, #fcfcfc, #dcdcdc, #fcfcfc);
    background: -webkit-linear-gradient(to top, #fcfcfc, #dcdcdc, #fcfcfc);
    background: -ms-linear-gradient(to top, #fcfcfc, #dcdcdc, #fcfcfc);
    background: -o-linear-gradient(to top, #fcfcfc, #dcdcdc, #fcfcfc);
    background: linear-gradient(to top, #fcfcfc, #dcdcdc, #fcfcfc);
    border-bottom-color: #fff;
}

input.sheet-tab:not(:first-child)::before
{
    border-left: none;
}

div.sheet-tab-content
{
    background: #D6F5FF;
    border: 1px solid #a8a8a8;
    border-top-color: #000;
    margin: 2px 0 0 5px;
    padding: 5px;
}

/*drives*/

div.sheet-tab-content { display: none; }

input.sheet-tab1:checked ~ div.sheet-tab1,
input.sheet-tab2:checked ~ div.sheet-tab2,
input.sheet-tab3:checked ~ div.sheet-tab3,
input.sheet-tab4:checked ~ div.sheet-tab4,
input.sheet-tab5:checked ~ div.sheet-tab5,
input.sheet-tab6:checked ~ div.sheet-tab6,
{
    display: block;
}

input.sheet-drivetab
{
    width: 19%;
    height: 20px;
    position: relative;
    top: 5px;
    left: 6px;
    margin: -1.5px;
    cursor: pointer;
    z-index: 1;
}

input.sheet-drivetab::before
{
    content: attr(title);

    border: solid 1px #a8a8a8;
    border-bottom-color: black;
    text-align: center;
    display: inline-block;
    
    background: #fff;
    background: -moz-linear-gradient(to top, #c8c8c8, #fff, #c8c8c8);
    background: -webkit-linear-gradient(to top, #c8c8c8, #fff, #c8c8c8);
    background: -ms-linear-gradient(to top, #c8c8c8, #fff, #c8c8c8);
    background: -o-linear-gradient(to top, #c8c8c8, #fff, #c8c8c8);
    background: linear-gradient(to top, #c8c8c8, #fff, #c8c8c8);
    width: 100%;
    height: 20px;
    font-size: 18px;
}

input.sheet-drivetab:checked::before
{
    background: #dcdcdc;
    background: -moz-linear-gradient(to top, #fcfcfc, #dcdcdc, #fcfcfc);
    background: -webkit-linear-gradient(to top, #fcfcfc, #dcdcdc, #fcfcfc);
    background: -ms-linear-gradient(to top, #fcfcfc, #dcdcdc, #fcfcfc);
    background: -o-linear-gradient(to top, #fcfcfc, #dcdcdc, #fcfcfc);
    background: linear-gradient(to top, #fcfcfc, #dcdcdc, #fcfcfc);
    border-bottom-color: #fff;
}

input.sheet-drivetab:not(:first-child)::before
{
    border-left: none;
}

div.sheet-drivetab-content
{
    background: #D6F5FF;
    border: 1px solid #a8a8a8;
    border-top-color: #000;
    margin: 2px 0 0 5px;
    padding: 5px;
}