Bug with location map width relative

By default, the location map is 400x300px. It can be change in the settings, but the 100% width doesn’t fit because, as I understand it, no upper div’s has an absolute width :

<div class="entry-content">
<div style="float:right; margin:0px 0px 15px 15px;">
<div class="em-location-map-container" style="position:relative; background: #CDCDCD; width: 100%; height: 300px;">

The problem appears to me including events-manager in a responsive theme : for the small screen (<400px) the map is too large when all the rest is perfectly fine.

How may I resolve the problem?

PS: Thanks for this great plugin.