RWD 2
#wrapper {width:95%; margin: 0 auto; }
#header {width:100%; }
#content {width:100%; }
#sidebar {width:100%; }
#footer {width:100%; }
// Small devices (landscape phones, 576px and up)
@media (min-width: 576px) {
// Medium devices (tablets, 768px and up)
@media (min-width: 768px) {
#wrapper {width:90%; margin: 0 auto; }
#content {width:70%; float:left; }
#sidebar {width:30%; float:right; }
// Large devices (desktops, 992px and up)
@media (min-width: 992px) { ... }
}
// Extra large devices (large desktops, 1200px and up)
@media (min-width: 1200px) {
#wrapper {width:90%; margin: 0 auto; }
}