* { margin:0; padding:0; box-sizing:border-box }
body div.header, body div.footer, body div.container
 { float:left; width:100% }
body.margin div.header, body.margin div.footer, body.margin div.container
 { width:98%; margin:0 1% }
body div.container > div.content
 { float:left; width:100% }
/*body div.container > div.content.left,
body div.container > div.content.right
 { overflow:hidden; background-color:inherit }*/
body div.container.opaque > div.content.left,
body div.container.opaque > div.content.right
 { position:relative; height:100% }

@media all and (min-width:600px) {
  body div.container > div.content.left { width:20% }
  body div.container > div.content.main { width:80% }
  body.margin div.header, body.margin div.footer, body.margin div.container
   { width:75%; margin:0 12.5% }
}
@media all and (min-width: 1280px) {
  body.margin div.header, body.margin div.footer, body.margin div.container
    { width:83.34%; margin-left:8.33%; margin-right:8.33% }
    /*{ width:87.5%; margin-left:6.25%; margin-right:6.25% }*/
}
@media all and (min-width: 1440px) {
  body.margin div.header, body.margin div.footer, body.margin div.container
    { width:66.68%; margin-left:16.66%; margin-right:16.66% }
}
@media all and (min-width:1920px) {
  body.margin div.header, body.margin div.footer, body.margin div.container
   { width:58.35%; margin-left:20.825%; margin-right:20.825% }
  body div.container > div.content.left,
  body div.container > div.content.right
   { width:16.66%; /*margin:0*/ } 
  body div.container > div.content.main { width:83.33% }
/*  body > div.body.margin > div.header, body > div.body.margin > div.footer,
  body > div.body.margin > div.container
   { width:60%; margin:0 20% }*/
}