div/span/css problem

ok, i am having problems dynamically resizing a div element.....

i have a three column section, each column is created using a span, the three spans are contained within a div element as follows:

<div style="height:auto; width:auto;">
<span style="float:left; height:auto; min-height:120px; padding-bottom:20px; width:15%;">blah blah</span>

<span style="float:right; height:auto; min-height:120px; padding-bottom:20px; width:71%;">blah blah</span>

<span style="clear:both; height:auto; min-height:120px; padding-bottom:20px; width:14%;">blah blah</span>
</div>


..... this is what i have so far, but like i said i cannot get it to dynamically change with the content in the span elements.....

ok nm i think i have it working.... for now