#body{ margin: 0px;
   
    





}
#anh{ height: 100vh;
    width: 100vw;
    opacity: 0.5;

}
#trangweb{
    border: 1px,yellow,solid;
    border-radius: 10px;
    text-decoration: none;
    font-size: 30px;
    height: 50px;
    width: 200px;
    background-color: yellow;
    display: flex;
    justify-content: center;
    align-items: center;
    position: absolute;
    

}
#longin{ display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
    position: relative;




}