Display block without 100% width

Use display: table.

This answer must be at least 30 characters; I entered 20, so here's a few more.

If I'm understanding your question properly, the following CSS will float your a below the spans and keep it from having a 100% width:

a {
    display: block; 
    float: left; 
    clear: left; 
}

you can use:

width: max-content;

Note: support is limited, check here for a full breakdown of supporting browsers