wpf - XAML => HTML Equivalent for AutoSize in Grid -

i'm working on converter xaml html! i've problem need convert grid html. use css grid this. problem is, when have columnwidth of "auto" in wpf, it's not same in html! in wpf column sizes of content! how can in html?

why not using html table? autosize like:

td {     width: 1px;     white-space: nowrap; }