.header{
    width: 100%;
    height: 50px;
    position: "relative";
    background-color: gray;
    margin-left: "10px";   


}

.Cajaloginheader
{
    width: 200x;
    height: 30px;
    font: inherit;
    border: 1px #000 ;
}

.cajalogincuerpo{
    box-sizing: content-box;
}