app.less

html, body {
    margin: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.flex-horiz {
    display: flex;
    flex-direction: row;
    height: 100%;
}

.flex-vert {
    display: flex;
    flex-direction: column;
    height: 100%;
}


.flex-horiz > *, .flex-vert > * {
    flex-grow: 1;
    flex-shrink: 1;
    flex-basis: 1px;
    position: relative;
}

.flex-horiz .flex-shrink, .flex-vert .flex-shrink {
    flex-grow: 0;
    flex-shrink: 1;
}

.flex-horiz .flex-grow, .flex-vert .flex-grow {
    flex-grow: 1;
    flex-shrink: 0;
}

.flex-reset {
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
    width: 100%;
    height: 100%;
}

body {
    font-family: "Segoe UI", Frutiger, "Frutiger Linotype", "Dejavu Sans", "Helvetica Neue", Arial, sans-serif;
}

.section {
    background: #e3e3e3; 
    padding: 20px; 
    font-size: 22px;
}

.section.top {
    border-bottom: 1px solid #c2c2c2;
}

.section.bottom {
    border-top: 1px solid #c2c2c2;
    font-size: 16px;
    text-align: right;
}