div.is-style-third figure, figure.is-style-third, #editor figure.is-style-third {
    width: 33%;
    max-width: 370px;
}
figure.is-style-third.alignright {
    margin-right: auto;
}
figure.is-style-third.alignleft {
    margin-left: auto;
}
figure.is-style-third:not(.alignleft):not(.alignright) {
    margin-right: auto;
    margin-left: auto;
}