* {
    box-sizing: border-box;
}

body {
    margin: 0;
    min-height: 100vh;

    background:
        radial-gradient(
            circle at top,
            #18202b 0%,
            #080b10 45%,
            #030405 100%
        );

    color: #ffffff;

    font-family:
        Arial,
        Helvetica,
        sans-serif;

    display: flex;
    align-items: center;
    justify-content: center;
}

.container {
    width: 100%;
    max-width: 600px;

    padding: 30px;
}

.logo {
    text-align: center;

    font-size: 36px;
    font-weight: 900;

    letter-spacing: 5px;

    margin-bottom: 30px;

    text-shadow:
        0 0 10px rgba(255,255,255,.4),
        0 0 30px rgba(80,160,255,.25);
}

.card {
    background: rgba(20, 25, 33, .95);

    border: 1px solid #303844;

    border-radius: 18px;

    padding: 40px;

    text-align: center;

    box-shadow:
        0 20px 60px rgba(0,0,0,.5);
}

.card h1 {
    margin-top: 0;

    font-size: 28px;
}

.card p {
    color: #b8c0ca;

    line-height: 1.6;
}

.username {
    color: #ffffff !important;

    font-size: 18px;
}

.button {
    display: inline-block;

    margin-top: 20px;

    padding: 14px 25px;

    border-radius: 10px;

    background: #1677ff;

    color: white;

    text-decoration: none;

    font-weight: bold;

    transition:
        transform .15s,
        opacity .15s;
}

.button:hover {
    transform: translateY(-2px);
    opacity: .9;
}

.button.secondary {
    background: #303844;
}

.device-code {
    margin: 25px 0;

    padding: 20px;

    background: #080b10;

    border: 1px solid #3b4655;

    border-radius: 12px;

    font-size: 32px;

    font-weight: bold;

    letter-spacing: 5px;
}

.small {
    font-size: 13px;
}

.error {
    margin-bottom: 20px;

    padding: 15px;

    border-radius: 10px;

    background: rgba(180, 40, 40, .2);

    border: 1px solid #8d3838;

    color: #ffaaaa;
}