.options-list {

}

.option-item {
    margin: 5px;
    border-radius: 4px;
}

.option-selected {
    border: solid 2px red;
}

/* для мобилок <= 700px */
@media screen and (max-width: 701px) {
    .product-container {
        display: flex;
        flex-direction: column;
    }
    #product-photo-container {
        display: flex;
        flex-wrap: wrap;
        justify-content: center;
        margin-bottom: 2em;
    }
    #product-photo {
        width: 90%;
        height: auto;
    }
}

/* для экранов > 700px */
@media screen and (min-width: 700px) {
    .product-container {
        display: flex;
        flex-direction: row;
    }
    #product-photo-container {
        margin-right: 2em;
    }
    #product-photo {
        max-width: 500px;
        min-width: 50%;
        height: auto;
    }
}