*{
    margin:0;
    padding:0;
    box-sizing:border-box;
    font-family:Arial, Helvetica, sans-serif;
}

body{
    background:#0d1117;
    color:white;
    min-height:100vh;
    display:flex;
    justify-content:center;
    align-items:center;
}

.container{
    width:100%;
    display:flex;
    justify-content:center;
    align-items:center;
}

.card{
    width:420px;
    background:#161b22;
    border:1px solid #30363d;
    border-radius:15px;
    padding:40px;
    text-align:center;
}

h1{
    margin-bottom:10px;
}

.subtitle{
    color:#8b949e;
    margin-bottom:25px;
}

input{
    width:100%;
    padding:12px;
    margin-bottom:15px;
    background:#0d1117;
    border:1px solid #30363d;
    border-radius:8px;
    color:white;
}

button{
    width:100%;
    padding:12px;
    border:none;
    border-radius:8px;
    cursor:pointer;
    background:#238636;
    color:white;
    font-size:15px;
}

button:hover{
    background:#2ea043;
}

.message{
    margin-top:15px;
    color:#ff7b72;
}

.footer{
    margin-top:25px;
    color:#8b949e;
    font-size:13px;
}

.flag-box{
    background:#0d1117;
    border:1px solid #30363d;
    border-radius:8px;
    padding:20px;
}