from textual.app import App, ComposeResult from textual.containers import Horizontal from textual.widgets import Static class HeightApp(App[None]): CSS = """ Horizontal { border: solid red; height: auto; } Static { border: solid green; width: auto; } #fill_parent { height: 100%; } #static { height: 16; } """ def compose(self) -> ComposeResult: yield Horizontal( Static("As tall as container", id="fill_parent"), Static("This has default\nheight\nbut a\nfew lines"), Static("I have a static height", id="static"), ) if __name__ == "__main__": HeightApp().run()