@media (max-width: 716px) {
    .letters-list {
        max-width: 455px;
    }

    .letters-list li {
        width: 35px;
        padding: 5px 0;
        display: inline-block;
    }
}

@media (max-width: 485px) {
    .letters-list li {
        width: 11.111111111%;
    }
}