<div id="wrap">
  <div id="header"></div>
  <div id="nav"></div>
  <div id="aside"></div>
  <div id="section"></div>
  <div id="footer"></div>
</div>

* {
  margin: 0;
}
body {
  background-color: #FFF3E0;
}
#wrap {
  width: 1200px;
  margin: 0 auto;
}
#header {
  width: 100%;
  height: 100px;
  background-color: #FFE0B2;
}
#nav {
  width: 100%;
  height: 100px;
  background-color: #FFCC80;
}
#aside {
  width: 25%;
  height: 780px;
  background-color: #FFB74D;
  float: left;
}
#section {
  width: 75%;
  height: 780px;
  background-color: #FFA726;
  float: left;
}
#footer {
  width: 100%;
  height: 100px;
  background-color: #FF9800;
  clear: both;
}

@media( max-width : 1300px ){
  #wrap {
    width: 96%;
  }
}
@media( max-width : 768px ){
  #wrap {
    width : 100%
  }
}
@media( max-width : 480px ){
  #wrap {
    width : 100%
  }
  #aside {
    width: 100%;
    height: 300px;
  } 
  #section {
    width: 100%;
    height: 480px;
  }

}