.abcd {overflow: hidden;
    white-space: nowrap; /* Убираем переносы */
    animation: begstroc 20s linear infinite normal;
    color: navy;
    font-size: 26px;
    font-weight: bold;
}   
 @keyframes begstroc {
    from { margin-left: 500px; }
    to { margin-left: -900px; }
}