* { margin: 0px; box-sizing: border-box; vertical-align: top; } html, body { height: 100%; } #textboxes { height: 40%; width: 100%; font-size: 0px; } textarea { resize: none; width: 33.3333%; height: 100%; } iframe { width: 100%; height: 60%; } textarea, iframe { border: 0.5px solid; } a, button { background: black; color: limegreen; text-decoration: none; padding: 2px 5px; border: none; } #bottomleft-buttons { position: absolute; bottom: 0; left: 0; } #topright-buttons { position: absolute; top: 0; right: 0; } form { display: inline; } label, input[type="checkbox"] { vertical-align: middle; } label { padding: 5px; padding-bottom: 0; padding-top: 0; background: white; color: black; }