body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: #eef2f3;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
}

.card {
    background: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
    text-align: center;
    width: 350px;
}

h2 { margin-top: 0; color: #333; }
p { color: #666; font-size: 14px; }

input {
    width: 100%;
    padding: 12px;
    margin: 20px 0;
    border: 2px solid #ddd;
    border-radius: 8px;
    box-sizing: border-box;
    outline: none;
    transition: border-color 0.3s;
}

input:focus { border-color: #007bff; }

.button-group {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}

button {
    flex: 1;
    padding: 12px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-weight: bold;
    transition: opacity 0.2s;
}

#generate-btn { background: #007bff; color: white; }
#download-btn { background: #28a745; color: white; }
#download-btn:disabled { background: #ccc; cursor: not-allowed; }

button:hover:not(:disabled) { opacity: 0.9; }

#qrcode {
    margin-top: 10px;
    display: flex;
    justify-content: center;
    padding: 10px;
    background: #f9f9f9;
    border-radius: 8px;
    min-height: 128px;
}

#qrcode img {
    border: 4px solid white;
}