html - Centered Absoloute div to big -

my problem have 2 divs should support min screen resolution of 1000px in scenario pushs me 143px out of viewport (scrollbar appears) (643 width) because it's first positioned left:50% , left:-50%. idea how can solve it. it's little harsh explain, attached screenshot.

<div id="outter">  <div id="inner"></div> </div> 

the css is:

#outter{ position: absolute; height: 350px; width: 643px; margin: -245px auto; left:50%; z-index: 3; }  #inner { position: relative; left: -50%; } 

in field of web design , development, we’re getting point of being unable keep endless new resolutions , devices. many websites, creating website version each resolution , new device impossible, or @ least impractical. soo fictional responsive webdesign, in case solution. work :)