.hidden{ visibility: hidden; } html{ height: 100%; } body{ display: flex; flex-direction: row; flex-wrap: nowrap; justify-content: space-around; align-items: stretch; /* height: 100%; */ height: 100%; margin: 0; padding: 0; } div.enigme{ width: 33%; height: 100%; margin: 0; padding: 0; } div.editor_class{ width: 33%; min-height: 100%; margin-bottom: 0; } div.compiler_class{ width: 33%; }