text area in html jumps on focus

[TheCat]

i have a html tag for text area as below...\[code\]<div> <span class="l" style="padding-top: 77px"> <textarea id="txt7" rows="3" cols="50">Lorem ipsum</textarea> </span></div>\[/code\]on focus i am changing border color and border width it worked fine.the problem when i do focus on that element text area box jumps on the page (means moves a little bit....)css:\[code\]textarea:focus { .br; border-style: solid; .shdw; }\[/code\]so any work around to this plz.............how abt using box-shawdow property .....i am not aware of using it ........so do any help there on this............