:root
{
    --color_3d_shadow: rgba(0, 0, 0, 0.5);
    --color_3d_highlight: rgba(255, 255, 255, 0.5);
}

body
{
    display: flex;
    flex-direction: column;
    background-color:#fff;
    margin: 8px;
}
#header
{
    display: flex;
    flex-direction: row;
    justify-content: center;
    align-content: center;
    margin-bottom: 4px;
}
.header_element
{
    display: flex;
    justify-content: center;
    flex: 1;
    background-color: rgba(0, 0, 0, 0.1);   
}
.header_element:hover
{
    background-color: rgba(0, 0, 0, 0.2);
}
.hidden
{
    display: none !important;
}
#content_body
{
    flex: 0 0 auto;
    display: flex;
    flex-direction: row;
}


button,
button *
{
    color: black;
}
button:disabled
{
    background-color: #cccccc !important;
}
button
{
    border-top: 2px solid var(--color_3d_highlight);
    border-left: 2px solid var(--color_3d_highlight);
    border-right: 2px solid var(--color_3d_shadow);
    border-bottom: 2px solid var(--color_3d_shadow);
}
button:active
{
    border-top: 2px solid var(--color_3d_shadow);
    border-left: 2px solid var(--color_3d_shadow);
    border-right: 2px solid var(--color_3d_highlight);
    border-bottom: 2px solid var(--color_3d_highlight);
}
.gray_button
{
    background-color: #cccccc;
}
.green_button
{
    background-color: #6df16f;
}
.red_button
{
    background-color: #ff4949;
}
.yellow_button
{
    background-color: #ffea57;
}