.ide { display: flex; flex-direction: row; height: 100%; flex-wrap: wrap; } .editor-holder { flex: 1 0 0; max-width: 45%; height: 100%; } .preview-frame { flex: 1 0 0; } .toolbar { width: 100%; } .sidebar { width: #{180 / $base-font-size}rem; &.sidebar--contracted { width: #{20 / $base-font-size}rem; } }