@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

        body {
            font-family: 'Inter', 'Microsoft YaHei', sans-serif;
        }

        .card-shadow {
            box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
        }

        .loading-spinner {
            display: inline-block;
            width: 16px;
            height: 16px;
            border: 2px solid #e5e7eb;
            border-radius: 50%;
            border-top-color: #3b82f6;
            animation: spin 1s ease-in-out infinite;
        }

        @keyframes spin {
            to {
                transform: rotate(360deg);
            }
        }

        .flag-icon {
            width: 20px;
            height: 20px;
            border-radius: 50%;
            object-fit: cover;
        }

        .accordion-content {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.3s ease-out;
        }

        .accordion-content.active {
            max-height: 300px;
        }

        .rtt-result {
            transition: all 0.3s ease;
        }

        .security-notice {
            background: linear-gradient(to right, rgb(222, 97, 97), rgb(38, 87, 235));
            animation: slideIn 0.5s ease-out;
        }

        @keyframes slideIn {
            from {
                opacity: 0;
                transform: translateY(-10px);
            }

            to {
                opacity: 1;
                transform: translateY(0);
            }
        }