body {
    background: radial-gradient(circle at 50% 50%, #f8fafc 0%, #f1f5f9 100%);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
}
.card {
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    padding: 40px;
    border-radius: 16px;
    text-align: center;
    max-width: 440px;
    width: 90%;
    border: 1px solid rgba(226, 232, 240, 0.8);
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.05);
}
.loader {
    border: 3.5px solid #e2e8f0;
    border-top: 3.5px solid #3b82f6;
    border-radius: 50%;
    width: 48px;
    height: 48px;
    animation: spin 1.0s cubic-bezier(0.4, 0, 0.2, 1) infinite;
    margin: 0 auto 24px;
}
h3 {
    color: #0f172a;
    margin-bottom: 12px;
    font-size: 1.15rem;
    font-weight: 600;
    line-height: 1.5;
}
.text-muted {
    color: #64748b;
    font-size: 0.88rem;
    line-height: 1.5;
    margin: 0;
}
@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}