.usdt-modal {
    display: none;
    position: fixed;
    z-index: 99999;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.8);
    overflow-y: auto;
}

.usdt-modal-content {
    background: #fff;
    margin: 50px auto;
    padding: 20px;
    width: 90%;
    max-width: 800px;
    border-radius: 8px;
    box-shadow: 0 5px 30px rgba(0,0,0,0.3);
    position: relative;
    animation: modalFadeIn 0.3s;
}

.usdt-close {
    position: absolute;
    right: 20px;
    top: 15px;
    font-size: 28px;
    cursor: pointer;
    color: #555;
}

@keyframes modalFadeIn {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
}