html { height: 100%; overflow: hidden; } body { height: 100%; font-family: sans-serif; font-size: 1.2rem; margin: 0; padding: 0; } #grist-app { height: 100%; display: -webkit-flex; display: flex; -webkit-flex-direction: column; flex-direction: column; -webkit-flex-wrap: nowrap; flex-wrap: nowrap; } .g-help { position: absolute; top: 10%; left: 10%; height: 80%; width: 80%; z-index: 999; padding: 1rem; background-color: rgba(0, 0, 0, .8); -webkit-border-radius: 1rem; -moz-border-radius: 1rem; border-radius: 1rem; color: #fff; font-size: 1.4rem; overflow: auto; } .g-help-table { width: 100%; margin-bottom: 2rem; }