.top {
        position:fixed;
        left:0; right:0;
        height: 50px;
        z-index: 20;
    }

    .middle {
        position:relative;
        left:178px; 
        right: 0;
        z-index: 10;
    }

    .left {
        position:fixed;
    height:100%;
    width: 180px;
    background-color: #ccc;  
    top: 50px;
    
    }
    .main {
        box-sizing:border-box;
        top: 115px;
    position:absolute;
    left:180px;
    width:calc(100% - 180px);
   
    }

.left { background: white; }

.navbar {
    margin-bottom: 0px;
    border: none;
}