How can i put a selectList in the right corner over the map

This is mai map component

<aura:component >
<aura:attribute name="map" type="Object"/>
<aura:handler event="c:AccountsLoaded" action="{!c.accountsLoaded}"/>
<aura:handler event="c:AccountSelected" action="{!c.accountSelected}"/>

<ltng:require styles="/resource/leaflet/leaflet.css"
scripts="/resource/leaflet/leaflet.js"
afterScriptsLoaded="{!c.jsLoaded}" />
<div id="map">
<c:RadiusListItem/> - this is the list of items that i want to display in the right corner of the map
</div>
</aura:component>