* {
        margin:0;
        padding:0;
    }    

    body {
        background:#E6E6E6;
        font-family: courier, courier new, serif;
    }
    
    .contenedor {
        margin: 0 auto;
        width: 100%;
        max-width:1400px;
        overflow:hidden;
    }
    
    header {
        background:#fff;
        margin:20px 0;
        border-radius:10px;
    }
    
    header img {
        width:30%;
        height:auto;
        float:center;
    }


    header h1 {
        color:#fff;
        padding:20px 0;
    }
    
    .main {
        width:25%;
        height:550px;
        background:#b7dabd;
        padding:20px;
        float: left;
        border-radius:10px;
        box-sizing:border-box;
    }
    
    aside img {
        width:100%;
        height:auto;
    }
    
    aside {
        width:40%;
        height:550px;
        padding:20px;
        box-sizing:border-box;
        background:#ccc;
        float:left;
        border-radius:10px;
    }
    
    aside1 {
        width:35%;
        height:550px;
        padding:20px;
        box-sizing:border-box;
        background:#fff;
        float:left;
        border-radius:10px;
    }

    
    footer {
        clear:both;
        float: left;
        margin-top:20px;
        box-sizing:border-box;
        width:100%;
        padding:20px;
        color:#fff;
        background:#0A2A22;
        border-radius:10px;
    }
    
    @media screen and (max-width: 800px){
        .main {
            width:100%;
            height:auto;
        }
        header img {
            width:100%;
        }

        aside {
            width:100%;
            height:auto;
        } 
        
        aside1 {
            width:100%;
            height:auto;
        }             
    }
    
    @media screen and (max-width: 400px){
        .main {
            display:none;
            height:auto;
        }
        header img {
            width:100%;
        }

        aside {
            width:100%;
            height:auto;
        }          
        
        aside1 {
            width:100%;
             height:auto;
       }             }
       .btn {
        display:block;
        width:200px;
        height:30px;
        background:#0A2A22;
        color:#fff;
        text-align:center;
        text-decoration:none;
        border-radius:5px;
        padding:5px;  
        align:center

    }
       .btn1 {
        width:100px;
        background:#1d796c;
        color:#fff;
        text-align:center;
        text-decoration:none;
        border-radius:5px;
        padding:5px;  

    }