.tab {
    text-align: center; /* Căn giữa ngang */
    margin-top: 20px;
    }

    .vien {
        padding: 8px 15px;
        border-radius: 10px;
        font-size: 18px;
        background-color: red;
        color: white;
        border: 1.5px solid;
        margin: 0 8px; 
        display: inline-block;
    }
    .vien1 {
        padding: 8px 15px;
        border-radius: 10px;
        font-size: 18px;
        background-color: green;
        color: white;
        border: 1.5px solid;
        margin: 0 8px; 
        display: inline-block;
    }
    .vien2 {
        padding: 8px 15px;
        border-radius: 10px;
        font-size: 18px;
        background-color: blue;
        color: white;
        border: 1.5px solid ;
        margin: 0 8px;
        display: inline-block;
    }
    .xtdev {
        padding: 15px;
        border-radius: 5px;
        font-size: 15px;
        
        margin-left: auto;
        display: inline-block;
    }
    .xtdev1 {
        padding: 0;
        border-radius: 10px;
        font-size: 10px;
      
        margin-left: auto;
        display: inline-block;
    }
     .gv1 {
        border-radius: 10px;
        border: 3px solid blue ;
    }
    
    
    .xtcolor {
    background-image: linear-gradient(to right,#0099FF,  #33CCFF);
    border:2px;
    border-radius: 10px;
    padding-left: auto;
}
.xtcolor:hover {
    background-image: linear-gradient(to right,#33CCFF , #0099FF);
    border:2px;
    border-radius: 10px;
    padding-left: auto;
}
.gn {
    border-radius: 15px;
    padding: 5px;
}
.gn1 {
    border-radius: 8px;
    padding-left: auto;
}
.gv1 {
        border-radius: 10px;
        border: 3px solid blue ;
    }