#index {
    height: 100%;
    width: 300px;
    float: left;
    padding: 5px;
}

#context {
    height: 100%;
    width: 100%;
    padding: 5px;
}

#button-menu {
    font-size: 30px;
    opacity: 0.7;
    position: absolute;
    top: 5px;
    left: 5px;
    display: none;
}
#button-menu a {
    text-decoration: none;
}

@media screen and (max-width: 700px) {
    #index {
        display: none;
        width: 100%;
        height: auto;
    }
    #button-menu {
        display: block;
    }
}

@media screen and (min-width: 700px) {
    #index {
        height: 100%;
        width: 300px;
        display: block;
    }
}