heigh pod div Opcje

[Randallmaster]

Witam serdecznie, posiadam taki kod:

[PHP] pobierz, plaintext 
div id="tekst1" style="height: 100%;">
<div style="float: left; width: 70%; height: 100%;     border-color: #cbcbc9; border-width: 0  1px 0 0; border-style: solid; padding: 10px; text-align: left;">
TREŚĆ
</div>
<div style="float: left; width: 25%; padding: 10px; text-align: center;">
 
<div style="border: 1px solid #cbcbc9; margin-left: 15px; padding: 5px;">
<form action="wyszukiwanie.php" id="cse-search-box">
  <div>
    <input type="hidden" name="cx" value="partner-pub-2904501938768162:ep95s6gxfm2" />
    <input type="hidden" name="cof" value="FORID:10" />
    <input type="hidden" name="ie" value="UTF-8" />
    <input type="text" name="q" size="20" />
    <input type="submit" name="sa" value="Szukaj" />
  </div>
</form>
<script type="text/javascript" src="http://www.google.com/cse/brand?form=cse-search-box&amp;lang=pl"></script> 
</div>
 
 
<div style="border: 1px solid #cbcbc9; margin-left: 15px; margin-top: 15px; padding: 5px;"><script type="text/javascript"><!--
google_ad_client = "pub-2904501938768162";
/* Reklama1 */
google_ad_slot = "4710229401";
google_ad_width = 120;
google_ad_height = 240;
//-->
</script>
<script type="text/javascript"
src="http://pagead2.googlesyndication.com/pagead/show_ads.js">
</script></div>
 
 
<div style="border: 1px solid #cbcbc9; margin-left: 15px; margin-top: 15px; padding: 5px;"><p><b>Partnerzy:</b><p>
<a href="http://www.mlodziezowy.konin.pl/" onMouseOver='rollover10.src="img/mk1.png"'
onMouseOut='rollover10.src="img/mk2.png"' target="_blank"><img src="img/mk2.png" name="rollover10" border="0"></a></div>
 
</div>
</div>
[PHP] pobierz, plaintext 

Niestety div tekst1 nie współgra z divem: <div style="float: left; width: 70%; height: 100%; border-color: #cbcbc9; border-width: 0 1px 0 0; border-style: solid; padding: 10px; text-align: left;"> co do wielkości height: 100%. Co zrobić aby div tekst 1 miał 100% wielkości względem drugiego diva? Proszę o pomoc